diff --git a/.circleci/config.yml b/.circleci/config.yml index 754c575bd3..806701a41e 100644 --- a/.circleci/config.yml +++ b/.circleci/config.yml @@ -16,7 +16,7 @@ jobs: steps: - checkout - run: make promu - - run: make check_license style unused staticcheck build + - run: make check_license staticcheck style unused build - run: git diff --exit-code - store_artifacts: path: prometheus diff --git a/.travis.yml b/.travis.yml index c6c4eafa97..46b819079a 100644 --- a/.travis.yml +++ b/.travis.yml @@ -10,5 +10,5 @@ go: go_import_path: github.com/prometheus/prometheus script: -- make check_license style unused test staticcheck +- make check_license staticcheck style unused test - git diff --exit-code diff --git a/Makefile.common b/Makefile.common index a397134b15..71afd5a290 100644 --- a/Makefile.common +++ b/Makefile.common @@ -33,21 +33,22 @@ ifneq (,$(wildcard go.mod)) ifeq ($(shell $(GO) version | grep -E 'go1\.(10|[0-9])\.'),) # Always use the local vendor/ directory to satisfy the dependencies. GOOPTS := $(GOOPTS) -mod=vendor - # Enable module support forcibly just in case the directory is inside GOPATH. + # Enable module support forcibly just in case the directory is inside GOPATH (and Travis CI). GO111MODULE := on unexport GOVENDOR + unexport STATICCHECK else $(warning This repository requires Go >= 1.11 because of Go modules) $(warning Some recipes may not work as expected as the current Go runtime is '$(shell $(GO) version)') endif else - # This repository isn't using Go modules (yet). +# This repository isn't using Go modules (yet). GOVENDOR := $(FIRST_GOPATH)/bin/govendor + STATICCHECK := $(FIRST_GOPATH)/bin/staticcheck GO111MODULE := auto endif PROMU := $(FIRST_GOPATH)/bin/promu -STATICCHECK := $(FIRST_GOPATH)/bin/staticcheck pkgs = ./... PREFIX ?= $(shell pwd) @@ -107,7 +108,11 @@ common-vet: .PHONY: common-staticcheck common-staticcheck: $(STATICCHECK) @echo ">> running staticcheck" - GO111MODULE=$(GO111MODULE) $(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" $(pkgs) +ifdef STATICCHECK + GO111MODULE=off $(STATICCHECK) -ignore "$(STATICCHECK_IGNORE)" $(pkgs) +else + GO111MODULE=$(GO111MODULE) $(GO) run $(GOOPTS) honnef.co/go/tools/cmd/staticcheck -ignore "$(STATICCHECK_IGNORE)" -checks "SA*" $(pkgs) +endif .PHONY: common-unused common-unused: $(GOVENDOR) @@ -149,11 +154,11 @@ common-docker-tag-latest: promu: GOOS= GOARCH= GO111MODULE=off $(GO) get -u github.com/prometheus/promu +ifneq (,$(wildcard go.mod)) .PHONY: $(STATICCHECK) $(STATICCHECK): GOOS= GOARCH= GO111MODULE=off $(GO) get -u honnef.co/go/tools/cmd/staticcheck -ifdef GOVENDOR .PHONY: $(GOVENDOR) $(GOVENDOR): GOOS= GOARCH= $(GO) get -u github.com/kardianos/govendor diff --git a/go.mod b/go.mod index 99cb80948e..1563ec0a37 100644 --- a/go.mod +++ b/go.mod @@ -3,6 +3,7 @@ module github.com/prometheus/prometheus require ( github.com/Azure/azure-sdk-for-go v0.0.0-20161028183111-bd73d950fa44 github.com/Azure/go-autorest v10.8.1+incompatible + github.com/BurntSushi/toml v0.3.1 // indirect github.com/OneOfOne/xxhash v1.2.2 // indirect github.com/StackExchange/wmi v0.0.0-20180725035823-b12b22c5341f // indirect github.com/VividCortex/ewma v1.1.1 // indirect @@ -142,6 +143,7 @@ require ( gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 // indirect gopkg.in/vmihailenco/msgpack.v2 v2.9.1 // indirect gopkg.in/yaml.v2 v2.2.0 + honnef.co/go/tools v0.0.0-20180910201051-f1b53a58b022 k8s.io/api v0.0.0-20180628040859-072894a440bd k8s.io/apimachinery v0.0.0-20180621070125-103fd098999d k8s.io/client-go v8.0.0+incompatible diff --git a/go.sum b/go.sum index 49ccdb976f..d016d69426 100644 --- a/go.sum +++ b/go.sum @@ -2,6 +2,8 @@ github.com/Azure/azure-sdk-for-go v0.0.0-20161028183111-bd73d950fa44 h1:L4fLiifs github.com/Azure/azure-sdk-for-go v0.0.0-20161028183111-bd73d950fa44/go.mod h1:9XXNKU+eRnpl9moKnB4QOLf1HestfXbmab5FXxiDBjc= github.com/Azure/go-autorest v10.8.1+incompatible h1:u0jVQf+a6k6x8A+sT60l6EY9XZu+kHdnZVPAYqpVRo0= github.com/Azure/go-autorest v10.8.1+incompatible/go.mod h1:r+4oMnoxhatjLLJ6zxSWATqVooLgysK6ZNox3g/xq24= +github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ= +github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU= github.com/OneOfOne/xxhash v1.2.2 h1:KMrpdQIwFcEqXDklaen+P1axHaj9BSKzvpUUfnHldSE= github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU= github.com/StackExchange/wmi v0.0.0-20180725035823-b12b22c5341f h1:5ZfJxyXo8KyX8DgGXC5B7ILL8y51fci/qYz2B4j8iLY= @@ -291,6 +293,8 @@ gopkg.in/vmihailenco/msgpack.v2 v2.9.1 h1:kb0VV7NuIojvRfzwslQeP3yArBqJHW9tOl4t38 gopkg.in/vmihailenco/msgpack.v2 v2.9.1/go.mod h1:/3Dn1Npt9+MYyLpYYXjInO/5jvMLamn+AEGwNEOatn8= gopkg.in/yaml.v2 v2.2.0 h1:ucE2Go3MGv/WipgucyA7X3+4pRLSbl5sd8WaEs60obQ= gopkg.in/yaml.v2 v2.2.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI= +honnef.co/go/tools v0.0.0-20180910201051-f1b53a58b022 h1:6BZ1uHan+VqtcF3xb+hOvKSWhvQy/nk+ZRtQJJLBWIM= +honnef.co/go/tools v0.0.0-20180910201051-f1b53a58b022/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4= k8s.io/api v0.0.0-20180628040859-072894a440bd h1:HzgYeLDS1jLxw8DGr68KJh9cdQ5iZJizG0HZWstIhfQ= k8s.io/api v0.0.0-20180628040859-072894a440bd/go.mod h1:iuAfoD4hCxJ8Onx9kaTIt30j7jUFS00AXQi6QMi99vA= k8s.io/apimachinery v0.0.0-20180621070125-103fd098999d h1:MZjlsu9igBoVPZkXpIGoxI6EonqNsXXZU7hhvfQLkd4= diff --git a/vendor/github.com/BurntSushi/toml/.gitignore b/vendor/github.com/BurntSushi/toml/.gitignore new file mode 100644 index 0000000000..0cd3800377 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/.gitignore @@ -0,0 +1,5 @@ +TAGS +tags +.*.swp +tomlcheck/tomlcheck +toml.test diff --git a/vendor/github.com/BurntSushi/toml/.travis.yml b/vendor/github.com/BurntSushi/toml/.travis.yml new file mode 100644 index 0000000000..8b8afc4f0e --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/.travis.yml @@ -0,0 +1,15 @@ +language: go +go: + - 1.1 + - 1.2 + - 1.3 + - 1.4 + - 1.5 + - 1.6 + - tip +install: + - go install ./... + - go get github.com/BurntSushi/toml-test +script: + - export PATH="$PATH:$HOME/gopath/bin" + - make test diff --git a/vendor/github.com/BurntSushi/toml/COMPATIBLE b/vendor/github.com/BurntSushi/toml/COMPATIBLE new file mode 100644 index 0000000000..6efcfd0ce5 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/COMPATIBLE @@ -0,0 +1,3 @@ +Compatible with TOML version +[v0.4.0](https://github.com/toml-lang/toml/blob/v0.4.0/versions/en/toml-v0.4.0.md) + diff --git a/vendor/github.com/BurntSushi/toml/COPYING b/vendor/github.com/BurntSushi/toml/COPYING new file mode 100644 index 0000000000..01b5743200 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/COPYING @@ -0,0 +1,21 @@ +The MIT License (MIT) + +Copyright (c) 2013 TOML authors + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in +all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +THE SOFTWARE. diff --git a/vendor/github.com/BurntSushi/toml/Makefile b/vendor/github.com/BurntSushi/toml/Makefile new file mode 100644 index 0000000000..3600848d33 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/Makefile @@ -0,0 +1,19 @@ +install: + go install ./... + +test: install + go test -v + toml-test toml-test-decoder + toml-test -encoder toml-test-encoder + +fmt: + gofmt -w *.go */*.go + colcheck *.go */*.go + +tags: + find ./ -name '*.go' -print0 | xargs -0 gotags > TAGS + +push: + git push origin master + git push github master + diff --git a/vendor/github.com/BurntSushi/toml/README.md b/vendor/github.com/BurntSushi/toml/README.md new file mode 100644 index 0000000000..7c1b37ecc7 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/README.md @@ -0,0 +1,218 @@ +## TOML parser and encoder for Go with reflection + +TOML stands for Tom's Obvious, Minimal Language. This Go package provides a +reflection interface similar to Go's standard library `json` and `xml` +packages. This package also supports the `encoding.TextUnmarshaler` and +`encoding.TextMarshaler` interfaces so that you can define custom data +representations. (There is an example of this below.) + +Spec: https://github.com/toml-lang/toml + +Compatible with TOML version +[v0.4.0](https://github.com/toml-lang/toml/blob/master/versions/en/toml-v0.4.0.md) + +Documentation: https://godoc.org/github.com/BurntSushi/toml + +Installation: + +```bash +go get github.com/BurntSushi/toml +``` + +Try the toml validator: + +```bash +go get github.com/BurntSushi/toml/cmd/tomlv +tomlv some-toml-file.toml +``` + +[![Build Status](https://travis-ci.org/BurntSushi/toml.svg?branch=master)](https://travis-ci.org/BurntSushi/toml) [![GoDoc](https://godoc.org/github.com/BurntSushi/toml?status.svg)](https://godoc.org/github.com/BurntSushi/toml) + +### Testing + +This package passes all tests in +[toml-test](https://github.com/BurntSushi/toml-test) for both the decoder +and the encoder. + +### Examples + +This package works similarly to how the Go standard library handles `XML` +and `JSON`. Namely, data is loaded into Go values via reflection. + +For the simplest example, consider some TOML file as just a list of keys +and values: + +```toml +Age = 25 +Cats = [ "Cauchy", "Plato" ] +Pi = 3.14 +Perfection = [ 6, 28, 496, 8128 ] +DOB = 1987-07-05T05:45:00Z +``` + +Which could be defined in Go as: + +```go +type Config struct { + Age int + Cats []string + Pi float64 + Perfection []int + DOB time.Time // requires `import time` +} +``` + +And then decoded with: + +```go +var conf Config +if _, err := toml.Decode(tomlData, &conf); err != nil { + // handle error +} +``` + +You can also use struct tags if your struct field name doesn't map to a TOML +key value directly: + +```toml +some_key_NAME = "wat" +``` + +```go +type TOML struct { + ObscureKey string `toml:"some_key_NAME"` +} +``` + +### Using the `encoding.TextUnmarshaler` interface + +Here's an example that automatically parses duration strings into +`time.Duration` values: + +```toml +[[song]] +name = "Thunder Road" +duration = "4m49s" + +[[song]] +name = "Stairway to Heaven" +duration = "8m03s" +``` + +Which can be decoded with: + +```go +type song struct { + Name string + Duration duration +} +type songs struct { + Song []song +} +var favorites songs +if _, err := toml.Decode(blob, &favorites); err != nil { + log.Fatal(err) +} + +for _, s := range favorites.Song { + fmt.Printf("%s (%s)\n", s.Name, s.Duration) +} +``` + +And you'll also need a `duration` type that satisfies the +`encoding.TextUnmarshaler` interface: + +```go +type duration struct { + time.Duration +} + +func (d *duration) UnmarshalText(text []byte) error { + var err error + d.Duration, err = time.ParseDuration(string(text)) + return err +} +``` + +### More complex usage + +Here's an example of how to load the example from the official spec page: + +```toml +# This is a TOML document. Boom. + +title = "TOML Example" + +[owner] +name = "Tom Preston-Werner" +organization = "GitHub" +bio = "GitHub Cofounder & CEO\nLikes tater tots and beer." +dob = 1979-05-27T07:32:00Z # First class dates? Why not? + +[database] +server = "192.168.1.1" +ports = [ 8001, 8001, 8002 ] +connection_max = 5000 +enabled = true + +[servers] + + # You can indent as you please. Tabs or spaces. TOML don't care. + [servers.alpha] + ip = "10.0.0.1" + dc = "eqdc10" + + [servers.beta] + ip = "10.0.0.2" + dc = "eqdc10" + +[clients] +data = [ ["gamma", "delta"], [1, 2] ] # just an update to make sure parsers support it + +# Line breaks are OK when inside arrays +hosts = [ + "alpha", + "omega" +] +``` + +And the corresponding Go types are: + +```go +type tomlConfig struct { + Title string + Owner ownerInfo + DB database `toml:"database"` + Servers map[string]server + Clients clients +} + +type ownerInfo struct { + Name string + Org string `toml:"organization"` + Bio string + DOB time.Time +} + +type database struct { + Server string + Ports []int + ConnMax int `toml:"connection_max"` + Enabled bool +} + +type server struct { + IP string + DC string +} + +type clients struct { + Data [][]interface{} + Hosts []string +} +``` + +Note that a case insensitive match will be tried if an exact match can't be +found. + +A working example of the above can be found in `_examples/example.{go,toml}`. diff --git a/vendor/github.com/BurntSushi/toml/decode.go b/vendor/github.com/BurntSushi/toml/decode.go new file mode 100644 index 0000000000..b0fd51d5b6 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/decode.go @@ -0,0 +1,509 @@ +package toml + +import ( + "fmt" + "io" + "io/ioutil" + "math" + "reflect" + "strings" + "time" +) + +func e(format string, args ...interface{}) error { + return fmt.Errorf("toml: "+format, args...) +} + +// Unmarshaler is the interface implemented by objects that can unmarshal a +// TOML description of themselves. +type Unmarshaler interface { + UnmarshalTOML(interface{}) error +} + +// Unmarshal decodes the contents of `p` in TOML format into a pointer `v`. +func Unmarshal(p []byte, v interface{}) error { + _, err := Decode(string(p), v) + return err +} + +// Primitive is a TOML value that hasn't been decoded into a Go value. +// When using the various `Decode*` functions, the type `Primitive` may +// be given to any value, and its decoding will be delayed. +// +// A `Primitive` value can be decoded using the `PrimitiveDecode` function. +// +// The underlying representation of a `Primitive` value is subject to change. +// Do not rely on it. +// +// N.B. Primitive values are still parsed, so using them will only avoid +// the overhead of reflection. They can be useful when you don't know the +// exact type of TOML data until run time. +type Primitive struct { + undecoded interface{} + context Key +} + +// DEPRECATED! +// +// Use MetaData.PrimitiveDecode instead. +func PrimitiveDecode(primValue Primitive, v interface{}) error { + md := MetaData{decoded: make(map[string]bool)} + return md.unify(primValue.undecoded, rvalue(v)) +} + +// PrimitiveDecode is just like the other `Decode*` functions, except it +// decodes a TOML value that has already been parsed. Valid primitive values +// can *only* be obtained from values filled by the decoder functions, +// including this method. (i.e., `v` may contain more `Primitive` +// values.) +// +// Meta data for primitive values is included in the meta data returned by +// the `Decode*` functions with one exception: keys returned by the Undecoded +// method will only reflect keys that were decoded. Namely, any keys hidden +// behind a Primitive will be considered undecoded. Executing this method will +// update the undecoded keys in the meta data. (See the example.) +func (md *MetaData) PrimitiveDecode(primValue Primitive, v interface{}) error { + md.context = primValue.context + defer func() { md.context = nil }() + return md.unify(primValue.undecoded, rvalue(v)) +} + +// Decode will decode the contents of `data` in TOML format into a pointer +// `v`. +// +// TOML hashes correspond to Go structs or maps. (Dealer's choice. They can be +// used interchangeably.) +// +// TOML arrays of tables correspond to either a slice of structs or a slice +// of maps. +// +// TOML datetimes correspond to Go `time.Time` values. +// +// All other TOML types (float, string, int, bool and array) correspond +// to the obvious Go types. +// +// An exception to the above rules is if a type implements the +// encoding.TextUnmarshaler interface. In this case, any primitive TOML value +// (floats, strings, integers, booleans and datetimes) will be converted to +// a byte string and given to the value's UnmarshalText method. See the +// Unmarshaler example for a demonstration with time duration strings. +// +// Key mapping +// +// TOML keys can map to either keys in a Go map or field names in a Go +// struct. The special `toml` struct tag may be used to map TOML keys to +// struct fields that don't match the key name exactly. (See the example.) +// A case insensitive match to struct names will be tried if an exact match +// can't be found. +// +// The mapping between TOML values and Go values is loose. That is, there +// may exist TOML values that cannot be placed into your representation, and +// there may be parts of your representation that do not correspond to +// TOML values. This loose mapping can be made stricter by using the IsDefined +// and/or Undecoded methods on the MetaData returned. +// +// This decoder will not handle cyclic types. If a cyclic type is passed, +// `Decode` will not terminate. +func Decode(data string, v interface{}) (MetaData, error) { + rv := reflect.ValueOf(v) + if rv.Kind() != reflect.Ptr { + return MetaData{}, e("Decode of non-pointer %s", reflect.TypeOf(v)) + } + if rv.IsNil() { + return MetaData{}, e("Decode of nil %s", reflect.TypeOf(v)) + } + p, err := parse(data) + if err != nil { + return MetaData{}, err + } + md := MetaData{ + p.mapping, p.types, p.ordered, + make(map[string]bool, len(p.ordered)), nil, + } + return md, md.unify(p.mapping, indirect(rv)) +} + +// DecodeFile is just like Decode, except it will automatically read the +// contents of the file at `fpath` and decode it for you. +func DecodeFile(fpath string, v interface{}) (MetaData, error) { + bs, err := ioutil.ReadFile(fpath) + if err != nil { + return MetaData{}, err + } + return Decode(string(bs), v) +} + +// DecodeReader is just like Decode, except it will consume all bytes +// from the reader and decode it for you. +func DecodeReader(r io.Reader, v interface{}) (MetaData, error) { + bs, err := ioutil.ReadAll(r) + if err != nil { + return MetaData{}, err + } + return Decode(string(bs), v) +} + +// unify performs a sort of type unification based on the structure of `rv`, +// which is the client representation. +// +// Any type mismatch produces an error. Finding a type that we don't know +// how to handle produces an unsupported type error. +func (md *MetaData) unify(data interface{}, rv reflect.Value) error { + + // Special case. Look for a `Primitive` value. + if rv.Type() == reflect.TypeOf((*Primitive)(nil)).Elem() { + // Save the undecoded data and the key context into the primitive + // value. + context := make(Key, len(md.context)) + copy(context, md.context) + rv.Set(reflect.ValueOf(Primitive{ + undecoded: data, + context: context, + })) + return nil + } + + // Special case. Unmarshaler Interface support. + if rv.CanAddr() { + if v, ok := rv.Addr().Interface().(Unmarshaler); ok { + return v.UnmarshalTOML(data) + } + } + + // Special case. Handle time.Time values specifically. + // TODO: Remove this code when we decide to drop support for Go 1.1. + // This isn't necessary in Go 1.2 because time.Time satisfies the encoding + // interfaces. + if rv.Type().AssignableTo(rvalue(time.Time{}).Type()) { + return md.unifyDatetime(data, rv) + } + + // Special case. Look for a value satisfying the TextUnmarshaler interface. + if v, ok := rv.Interface().(TextUnmarshaler); ok { + return md.unifyText(data, v) + } + // BUG(burntsushi) + // The behavior here is incorrect whenever a Go type satisfies the + // encoding.TextUnmarshaler interface but also corresponds to a TOML + // hash or array. In particular, the unmarshaler should only be applied + // to primitive TOML values. But at this point, it will be applied to + // all kinds of values and produce an incorrect error whenever those values + // are hashes or arrays (including arrays of tables). + + k := rv.Kind() + + // laziness + if k >= reflect.Int && k <= reflect.Uint64 { + return md.unifyInt(data, rv) + } + switch k { + case reflect.Ptr: + elem := reflect.New(rv.Type().Elem()) + err := md.unify(data, reflect.Indirect(elem)) + if err != nil { + return err + } + rv.Set(elem) + return nil + case reflect.Struct: + return md.unifyStruct(data, rv) + case reflect.Map: + return md.unifyMap(data, rv) + case reflect.Array: + return md.unifyArray(data, rv) + case reflect.Slice: + return md.unifySlice(data, rv) + case reflect.String: + return md.unifyString(data, rv) + case reflect.Bool: + return md.unifyBool(data, rv) + case reflect.Interface: + // we only support empty interfaces. + if rv.NumMethod() > 0 { + return e("unsupported type %s", rv.Type()) + } + return md.unifyAnything(data, rv) + case reflect.Float32: + fallthrough + case reflect.Float64: + return md.unifyFloat64(data, rv) + } + return e("unsupported type %s", rv.Kind()) +} + +func (md *MetaData) unifyStruct(mapping interface{}, rv reflect.Value) error { + tmap, ok := mapping.(map[string]interface{}) + if !ok { + if mapping == nil { + return nil + } + return e("type mismatch for %s: expected table but found %T", + rv.Type().String(), mapping) + } + + for key, datum := range tmap { + var f *field + fields := cachedTypeFields(rv.Type()) + for i := range fields { + ff := &fields[i] + if ff.name == key { + f = ff + break + } + if f == nil && strings.EqualFold(ff.name, key) { + f = ff + } + } + if f != nil { + subv := rv + for _, i := range f.index { + subv = indirect(subv.Field(i)) + } + if isUnifiable(subv) { + md.decoded[md.context.add(key).String()] = true + md.context = append(md.context, key) + if err := md.unify(datum, subv); err != nil { + return err + } + md.context = md.context[0 : len(md.context)-1] + } else if f.name != "" { + // Bad user! No soup for you! + return e("cannot write unexported field %s.%s", + rv.Type().String(), f.name) + } + } + } + return nil +} + +func (md *MetaData) unifyMap(mapping interface{}, rv reflect.Value) error { + tmap, ok := mapping.(map[string]interface{}) + if !ok { + if tmap == nil { + return nil + } + return badtype("map", mapping) + } + if rv.IsNil() { + rv.Set(reflect.MakeMap(rv.Type())) + } + for k, v := range tmap { + md.decoded[md.context.add(k).String()] = true + md.context = append(md.context, k) + + rvkey := indirect(reflect.New(rv.Type().Key())) + rvval := reflect.Indirect(reflect.New(rv.Type().Elem())) + if err := md.unify(v, rvval); err != nil { + return err + } + md.context = md.context[0 : len(md.context)-1] + + rvkey.SetString(k) + rv.SetMapIndex(rvkey, rvval) + } + return nil +} + +func (md *MetaData) unifyArray(data interface{}, rv reflect.Value) error { + datav := reflect.ValueOf(data) + if datav.Kind() != reflect.Slice { + if !datav.IsValid() { + return nil + } + return badtype("slice", data) + } + sliceLen := datav.Len() + if sliceLen != rv.Len() { + return e("expected array length %d; got TOML array of length %d", + rv.Len(), sliceLen) + } + return md.unifySliceArray(datav, rv) +} + +func (md *MetaData) unifySlice(data interface{}, rv reflect.Value) error { + datav := reflect.ValueOf(data) + if datav.Kind() != reflect.Slice { + if !datav.IsValid() { + return nil + } + return badtype("slice", data) + } + n := datav.Len() + if rv.IsNil() || rv.Cap() < n { + rv.Set(reflect.MakeSlice(rv.Type(), n, n)) + } + rv.SetLen(n) + return md.unifySliceArray(datav, rv) +} + +func (md *MetaData) unifySliceArray(data, rv reflect.Value) error { + sliceLen := data.Len() + for i := 0; i < sliceLen; i++ { + v := data.Index(i).Interface() + sliceval := indirect(rv.Index(i)) + if err := md.unify(v, sliceval); err != nil { + return err + } + } + return nil +} + +func (md *MetaData) unifyDatetime(data interface{}, rv reflect.Value) error { + if _, ok := data.(time.Time); ok { + rv.Set(reflect.ValueOf(data)) + return nil + } + return badtype("time.Time", data) +} + +func (md *MetaData) unifyString(data interface{}, rv reflect.Value) error { + if s, ok := data.(string); ok { + rv.SetString(s) + return nil + } + return badtype("string", data) +} + +func (md *MetaData) unifyFloat64(data interface{}, rv reflect.Value) error { + if num, ok := data.(float64); ok { + switch rv.Kind() { + case reflect.Float32: + fallthrough + case reflect.Float64: + rv.SetFloat(num) + default: + panic("bug") + } + return nil + } + return badtype("float", data) +} + +func (md *MetaData) unifyInt(data interface{}, rv reflect.Value) error { + if num, ok := data.(int64); ok { + if rv.Kind() >= reflect.Int && rv.Kind() <= reflect.Int64 { + switch rv.Kind() { + case reflect.Int, reflect.Int64: + // No bounds checking necessary. + case reflect.Int8: + if num < math.MinInt8 || num > math.MaxInt8 { + return e("value %d is out of range for int8", num) + } + case reflect.Int16: + if num < math.MinInt16 || num > math.MaxInt16 { + return e("value %d is out of range for int16", num) + } + case reflect.Int32: + if num < math.MinInt32 || num > math.MaxInt32 { + return e("value %d is out of range for int32", num) + } + } + rv.SetInt(num) + } else if rv.Kind() >= reflect.Uint && rv.Kind() <= reflect.Uint64 { + unum := uint64(num) + switch rv.Kind() { + case reflect.Uint, reflect.Uint64: + // No bounds checking necessary. + case reflect.Uint8: + if num < 0 || unum > math.MaxUint8 { + return e("value %d is out of range for uint8", num) + } + case reflect.Uint16: + if num < 0 || unum > math.MaxUint16 { + return e("value %d is out of range for uint16", num) + } + case reflect.Uint32: + if num < 0 || unum > math.MaxUint32 { + return e("value %d is out of range for uint32", num) + } + } + rv.SetUint(unum) + } else { + panic("unreachable") + } + return nil + } + return badtype("integer", data) +} + +func (md *MetaData) unifyBool(data interface{}, rv reflect.Value) error { + if b, ok := data.(bool); ok { + rv.SetBool(b) + return nil + } + return badtype("boolean", data) +} + +func (md *MetaData) unifyAnything(data interface{}, rv reflect.Value) error { + rv.Set(reflect.ValueOf(data)) + return nil +} + +func (md *MetaData) unifyText(data interface{}, v TextUnmarshaler) error { + var s string + switch sdata := data.(type) { + case TextMarshaler: + text, err := sdata.MarshalText() + if err != nil { + return err + } + s = string(text) + case fmt.Stringer: + s = sdata.String() + case string: + s = sdata + case bool: + s = fmt.Sprintf("%v", sdata) + case int64: + s = fmt.Sprintf("%d", sdata) + case float64: + s = fmt.Sprintf("%f", sdata) + default: + return badtype("primitive (string-like)", data) + } + if err := v.UnmarshalText([]byte(s)); err != nil { + return err + } + return nil +} + +// rvalue returns a reflect.Value of `v`. All pointers are resolved. +func rvalue(v interface{}) reflect.Value { + return indirect(reflect.ValueOf(v)) +} + +// indirect returns the value pointed to by a pointer. +// Pointers are followed until the value is not a pointer. +// New values are allocated for each nil pointer. +// +// An exception to this rule is if the value satisfies an interface of +// interest to us (like encoding.TextUnmarshaler). +func indirect(v reflect.Value) reflect.Value { + if v.Kind() != reflect.Ptr { + if v.CanSet() { + pv := v.Addr() + if _, ok := pv.Interface().(TextUnmarshaler); ok { + return pv + } + } + return v + } + if v.IsNil() { + v.Set(reflect.New(v.Type().Elem())) + } + return indirect(reflect.Indirect(v)) +} + +func isUnifiable(rv reflect.Value) bool { + if rv.CanSet() { + return true + } + if _, ok := rv.Interface().(TextUnmarshaler); ok { + return true + } + return false +} + +func badtype(expected string, data interface{}) error { + return e("cannot load TOML value of type %T into a Go %s", data, expected) +} diff --git a/vendor/github.com/BurntSushi/toml/decode_meta.go b/vendor/github.com/BurntSushi/toml/decode_meta.go new file mode 100644 index 0000000000..b9914a6798 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/decode_meta.go @@ -0,0 +1,121 @@ +package toml + +import "strings" + +// MetaData allows access to meta information about TOML data that may not +// be inferrable via reflection. In particular, whether a key has been defined +// and the TOML type of a key. +type MetaData struct { + mapping map[string]interface{} + types map[string]tomlType + keys []Key + decoded map[string]bool + context Key // Used only during decoding. +} + +// IsDefined returns true if the key given exists in the TOML data. The key +// should be specified hierarchially. e.g., +// +// // access the TOML key 'a.b.c' +// IsDefined("a", "b", "c") +// +// IsDefined will return false if an empty key given. Keys are case sensitive. +func (md *MetaData) IsDefined(key ...string) bool { + if len(key) == 0 { + return false + } + + var hash map[string]interface{} + var ok bool + var hashOrVal interface{} = md.mapping + for _, k := range key { + if hash, ok = hashOrVal.(map[string]interface{}); !ok { + return false + } + if hashOrVal, ok = hash[k]; !ok { + return false + } + } + return true +} + +// Type returns a string representation of the type of the key specified. +// +// Type will return the empty string if given an empty key or a key that +// does not exist. Keys are case sensitive. +func (md *MetaData) Type(key ...string) string { + fullkey := strings.Join(key, ".") + if typ, ok := md.types[fullkey]; ok { + return typ.typeString() + } + return "" +} + +// Key is the type of any TOML key, including key groups. Use (MetaData).Keys +// to get values of this type. +type Key []string + +func (k Key) String() string { + return strings.Join(k, ".") +} + +func (k Key) maybeQuotedAll() string { + var ss []string + for i := range k { + ss = append(ss, k.maybeQuoted(i)) + } + return strings.Join(ss, ".") +} + +func (k Key) maybeQuoted(i int) string { + quote := false + for _, c := range k[i] { + if !isBareKeyChar(c) { + quote = true + break + } + } + if quote { + return "\"" + strings.Replace(k[i], "\"", "\\\"", -1) + "\"" + } + return k[i] +} + +func (k Key) add(piece string) Key { + newKey := make(Key, len(k)+1) + copy(newKey, k) + newKey[len(k)] = piece + return newKey +} + +// Keys returns a slice of every key in the TOML data, including key groups. +// Each key is itself a slice, where the first element is the top of the +// hierarchy and the last is the most specific. +// +// The list will have the same order as the keys appeared in the TOML data. +// +// All keys returned are non-empty. +func (md *MetaData) Keys() []Key { + return md.keys +} + +// Undecoded returns all keys that have not been decoded in the order in which +// they appear in the original TOML document. +// +// This includes keys that haven't been decoded because of a Primitive value. +// Once the Primitive value is decoded, the keys will be considered decoded. +// +// Also note that decoding into an empty interface will result in no decoding, +// and so no keys will be considered decoded. +// +// In this sense, the Undecoded keys correspond to keys in the TOML document +// that do not have a concrete type in your representation. +func (md *MetaData) Undecoded() []Key { + undecoded := make([]Key, 0, len(md.keys)) + for _, key := range md.keys { + if !md.decoded[key.String()] { + undecoded = append(undecoded, key) + } + } + return undecoded +} diff --git a/vendor/github.com/BurntSushi/toml/doc.go b/vendor/github.com/BurntSushi/toml/doc.go new file mode 100644 index 0000000000..b371f396ed --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/doc.go @@ -0,0 +1,27 @@ +/* +Package toml provides facilities for decoding and encoding TOML configuration +files via reflection. There is also support for delaying decoding with +the Primitive type, and querying the set of keys in a TOML document with the +MetaData type. + +The specification implemented: https://github.com/toml-lang/toml + +The sub-command github.com/BurntSushi/toml/cmd/tomlv can be used to verify +whether a file is a valid TOML document. It can also be used to print the +type of each key in a TOML document. + +Testing + +There are two important types of tests used for this package. The first is +contained inside '*_test.go' files and uses the standard Go unit testing +framework. These tests are primarily devoted to holistically testing the +decoder and encoder. + +The second type of testing is used to verify the implementation's adherence +to the TOML specification. These tests have been factored into their own +project: https://github.com/BurntSushi/toml-test + +The reason the tests are in a separate project is so that they can be used by +any implementation of TOML. Namely, it is language agnostic. +*/ +package toml diff --git a/vendor/github.com/BurntSushi/toml/encode.go b/vendor/github.com/BurntSushi/toml/encode.go new file mode 100644 index 0000000000..d905c21a24 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/encode.go @@ -0,0 +1,568 @@ +package toml + +import ( + "bufio" + "errors" + "fmt" + "io" + "reflect" + "sort" + "strconv" + "strings" + "time" +) + +type tomlEncodeError struct{ error } + +var ( + errArrayMixedElementTypes = errors.New( + "toml: cannot encode array with mixed element types") + errArrayNilElement = errors.New( + "toml: cannot encode array with nil element") + errNonString = errors.New( + "toml: cannot encode a map with non-string key type") + errAnonNonStruct = errors.New( + "toml: cannot encode an anonymous field that is not a struct") + errArrayNoTable = errors.New( + "toml: TOML array element cannot contain a table") + errNoKey = errors.New( + "toml: top-level values must be Go maps or structs") + errAnything = errors.New("") // used in testing +) + +var quotedReplacer = strings.NewReplacer( + "\t", "\\t", + "\n", "\\n", + "\r", "\\r", + "\"", "\\\"", + "\\", "\\\\", +) + +// Encoder controls the encoding of Go values to a TOML document to some +// io.Writer. +// +// The indentation level can be controlled with the Indent field. +type Encoder struct { + // A single indentation level. By default it is two spaces. + Indent string + + // hasWritten is whether we have written any output to w yet. + hasWritten bool + w *bufio.Writer +} + +// NewEncoder returns a TOML encoder that encodes Go values to the io.Writer +// given. By default, a single indentation level is 2 spaces. +func NewEncoder(w io.Writer) *Encoder { + return &Encoder{ + w: bufio.NewWriter(w), + Indent: " ", + } +} + +// Encode writes a TOML representation of the Go value to the underlying +// io.Writer. If the value given cannot be encoded to a valid TOML document, +// then an error is returned. +// +// The mapping between Go values and TOML values should be precisely the same +// as for the Decode* functions. Similarly, the TextMarshaler interface is +// supported by encoding the resulting bytes as strings. (If you want to write +// arbitrary binary data then you will need to use something like base64 since +// TOML does not have any binary types.) +// +// When encoding TOML hashes (i.e., Go maps or structs), keys without any +// sub-hashes are encoded first. +// +// If a Go map is encoded, then its keys are sorted alphabetically for +// deterministic output. More control over this behavior may be provided if +// there is demand for it. +// +// Encoding Go values without a corresponding TOML representation---like map +// types with non-string keys---will cause an error to be returned. Similarly +// for mixed arrays/slices, arrays/slices with nil elements, embedded +// non-struct types and nested slices containing maps or structs. +// (e.g., [][]map[string]string is not allowed but []map[string]string is OK +// and so is []map[string][]string.) +func (enc *Encoder) Encode(v interface{}) error { + rv := eindirect(reflect.ValueOf(v)) + if err := enc.safeEncode(Key([]string{}), rv); err != nil { + return err + } + return enc.w.Flush() +} + +func (enc *Encoder) safeEncode(key Key, rv reflect.Value) (err error) { + defer func() { + if r := recover(); r != nil { + if terr, ok := r.(tomlEncodeError); ok { + err = terr.error + return + } + panic(r) + } + }() + enc.encode(key, rv) + return nil +} + +func (enc *Encoder) encode(key Key, rv reflect.Value) { + // Special case. Time needs to be in ISO8601 format. + // Special case. If we can marshal the type to text, then we used that. + // Basically, this prevents the encoder for handling these types as + // generic structs (or whatever the underlying type of a TextMarshaler is). + switch rv.Interface().(type) { + case time.Time, TextMarshaler: + enc.keyEqElement(key, rv) + return + } + + k := rv.Kind() + switch k { + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, + reflect.Int64, + reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, + reflect.Uint64, + reflect.Float32, reflect.Float64, reflect.String, reflect.Bool: + enc.keyEqElement(key, rv) + case reflect.Array, reflect.Slice: + if typeEqual(tomlArrayHash, tomlTypeOfGo(rv)) { + enc.eArrayOfTables(key, rv) + } else { + enc.keyEqElement(key, rv) + } + case reflect.Interface: + if rv.IsNil() { + return + } + enc.encode(key, rv.Elem()) + case reflect.Map: + if rv.IsNil() { + return + } + enc.eTable(key, rv) + case reflect.Ptr: + if rv.IsNil() { + return + } + enc.encode(key, rv.Elem()) + case reflect.Struct: + enc.eTable(key, rv) + default: + panic(e("unsupported type for key '%s': %s", key, k)) + } +} + +// eElement encodes any value that can be an array element (primitives and +// arrays). +func (enc *Encoder) eElement(rv reflect.Value) { + switch v := rv.Interface().(type) { + case time.Time: + // Special case time.Time as a primitive. Has to come before + // TextMarshaler below because time.Time implements + // encoding.TextMarshaler, but we need to always use UTC. + enc.wf(v.UTC().Format("2006-01-02T15:04:05Z")) + return + case TextMarshaler: + // Special case. Use text marshaler if it's available for this value. + if s, err := v.MarshalText(); err != nil { + encPanic(err) + } else { + enc.writeQuoted(string(s)) + } + return + } + switch rv.Kind() { + case reflect.Bool: + enc.wf(strconv.FormatBool(rv.Bool())) + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, + reflect.Int64: + enc.wf(strconv.FormatInt(rv.Int(), 10)) + case reflect.Uint, reflect.Uint8, reflect.Uint16, + reflect.Uint32, reflect.Uint64: + enc.wf(strconv.FormatUint(rv.Uint(), 10)) + case reflect.Float32: + enc.wf(floatAddDecimal(strconv.FormatFloat(rv.Float(), 'f', -1, 32))) + case reflect.Float64: + enc.wf(floatAddDecimal(strconv.FormatFloat(rv.Float(), 'f', -1, 64))) + case reflect.Array, reflect.Slice: + enc.eArrayOrSliceElement(rv) + case reflect.Interface: + enc.eElement(rv.Elem()) + case reflect.String: + enc.writeQuoted(rv.String()) + default: + panic(e("unexpected primitive type: %s", rv.Kind())) + } +} + +// By the TOML spec, all floats must have a decimal with at least one +// number on either side. +func floatAddDecimal(fstr string) string { + if !strings.Contains(fstr, ".") { + return fstr + ".0" + } + return fstr +} + +func (enc *Encoder) writeQuoted(s string) { + enc.wf("\"%s\"", quotedReplacer.Replace(s)) +} + +func (enc *Encoder) eArrayOrSliceElement(rv reflect.Value) { + length := rv.Len() + enc.wf("[") + for i := 0; i < length; i++ { + elem := rv.Index(i) + enc.eElement(elem) + if i != length-1 { + enc.wf(", ") + } + } + enc.wf("]") +} + +func (enc *Encoder) eArrayOfTables(key Key, rv reflect.Value) { + if len(key) == 0 { + encPanic(errNoKey) + } + for i := 0; i < rv.Len(); i++ { + trv := rv.Index(i) + if isNil(trv) { + continue + } + panicIfInvalidKey(key) + enc.newline() + enc.wf("%s[[%s]]", enc.indentStr(key), key.maybeQuotedAll()) + enc.newline() + enc.eMapOrStruct(key, trv) + } +} + +func (enc *Encoder) eTable(key Key, rv reflect.Value) { + panicIfInvalidKey(key) + if len(key) == 1 { + // Output an extra newline between top-level tables. + // (The newline isn't written if nothing else has been written though.) + enc.newline() + } + if len(key) > 0 { + enc.wf("%s[%s]", enc.indentStr(key), key.maybeQuotedAll()) + enc.newline() + } + enc.eMapOrStruct(key, rv) +} + +func (enc *Encoder) eMapOrStruct(key Key, rv reflect.Value) { + switch rv := eindirect(rv); rv.Kind() { + case reflect.Map: + enc.eMap(key, rv) + case reflect.Struct: + enc.eStruct(key, rv) + default: + panic("eTable: unhandled reflect.Value Kind: " + rv.Kind().String()) + } +} + +func (enc *Encoder) eMap(key Key, rv reflect.Value) { + rt := rv.Type() + if rt.Key().Kind() != reflect.String { + encPanic(errNonString) + } + + // Sort keys so that we have deterministic output. And write keys directly + // underneath this key first, before writing sub-structs or sub-maps. + var mapKeysDirect, mapKeysSub []string + for _, mapKey := range rv.MapKeys() { + k := mapKey.String() + if typeIsHash(tomlTypeOfGo(rv.MapIndex(mapKey))) { + mapKeysSub = append(mapKeysSub, k) + } else { + mapKeysDirect = append(mapKeysDirect, k) + } + } + + var writeMapKeys = func(mapKeys []string) { + sort.Strings(mapKeys) + for _, mapKey := range mapKeys { + mrv := rv.MapIndex(reflect.ValueOf(mapKey)) + if isNil(mrv) { + // Don't write anything for nil fields. + continue + } + enc.encode(key.add(mapKey), mrv) + } + } + writeMapKeys(mapKeysDirect) + writeMapKeys(mapKeysSub) +} + +func (enc *Encoder) eStruct(key Key, rv reflect.Value) { + // Write keys for fields directly under this key first, because if we write + // a field that creates a new table, then all keys under it will be in that + // table (not the one we're writing here). + rt := rv.Type() + var fieldsDirect, fieldsSub [][]int + var addFields func(rt reflect.Type, rv reflect.Value, start []int) + addFields = func(rt reflect.Type, rv reflect.Value, start []int) { + for i := 0; i < rt.NumField(); i++ { + f := rt.Field(i) + // skip unexported fields + if f.PkgPath != "" && !f.Anonymous { + continue + } + frv := rv.Field(i) + if f.Anonymous { + t := f.Type + switch t.Kind() { + case reflect.Struct: + // Treat anonymous struct fields with + // tag names as though they are not + // anonymous, like encoding/json does. + if getOptions(f.Tag).name == "" { + addFields(t, frv, f.Index) + continue + } + case reflect.Ptr: + if t.Elem().Kind() == reflect.Struct && + getOptions(f.Tag).name == "" { + if !frv.IsNil() { + addFields(t.Elem(), frv.Elem(), f.Index) + } + continue + } + // Fall through to the normal field encoding logic below + // for non-struct anonymous fields. + } + } + + if typeIsHash(tomlTypeOfGo(frv)) { + fieldsSub = append(fieldsSub, append(start, f.Index...)) + } else { + fieldsDirect = append(fieldsDirect, append(start, f.Index...)) + } + } + } + addFields(rt, rv, nil) + + var writeFields = func(fields [][]int) { + for _, fieldIndex := range fields { + sft := rt.FieldByIndex(fieldIndex) + sf := rv.FieldByIndex(fieldIndex) + if isNil(sf) { + // Don't write anything for nil fields. + continue + } + + opts := getOptions(sft.Tag) + if opts.skip { + continue + } + keyName := sft.Name + if opts.name != "" { + keyName = opts.name + } + if opts.omitempty && isEmpty(sf) { + continue + } + if opts.omitzero && isZero(sf) { + continue + } + + enc.encode(key.add(keyName), sf) + } + } + writeFields(fieldsDirect) + writeFields(fieldsSub) +} + +// tomlTypeName returns the TOML type name of the Go value's type. It is +// used to determine whether the types of array elements are mixed (which is +// forbidden). If the Go value is nil, then it is illegal for it to be an array +// element, and valueIsNil is returned as true. + +// Returns the TOML type of a Go value. The type may be `nil`, which means +// no concrete TOML type could be found. +func tomlTypeOfGo(rv reflect.Value) tomlType { + if isNil(rv) || !rv.IsValid() { + return nil + } + switch rv.Kind() { + case reflect.Bool: + return tomlBool + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, + reflect.Int64, + reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, + reflect.Uint64: + return tomlInteger + case reflect.Float32, reflect.Float64: + return tomlFloat + case reflect.Array, reflect.Slice: + if typeEqual(tomlHash, tomlArrayType(rv)) { + return tomlArrayHash + } + return tomlArray + case reflect.Ptr, reflect.Interface: + return tomlTypeOfGo(rv.Elem()) + case reflect.String: + return tomlString + case reflect.Map: + return tomlHash + case reflect.Struct: + switch rv.Interface().(type) { + case time.Time: + return tomlDatetime + case TextMarshaler: + return tomlString + default: + return tomlHash + } + default: + panic("unexpected reflect.Kind: " + rv.Kind().String()) + } +} + +// tomlArrayType returns the element type of a TOML array. The type returned +// may be nil if it cannot be determined (e.g., a nil slice or a zero length +// slize). This function may also panic if it finds a type that cannot be +// expressed in TOML (such as nil elements, heterogeneous arrays or directly +// nested arrays of tables). +func tomlArrayType(rv reflect.Value) tomlType { + if isNil(rv) || !rv.IsValid() || rv.Len() == 0 { + return nil + } + firstType := tomlTypeOfGo(rv.Index(0)) + if firstType == nil { + encPanic(errArrayNilElement) + } + + rvlen := rv.Len() + for i := 1; i < rvlen; i++ { + elem := rv.Index(i) + switch elemType := tomlTypeOfGo(elem); { + case elemType == nil: + encPanic(errArrayNilElement) + case !typeEqual(firstType, elemType): + encPanic(errArrayMixedElementTypes) + } + } + // If we have a nested array, then we must make sure that the nested + // array contains ONLY primitives. + // This checks arbitrarily nested arrays. + if typeEqual(firstType, tomlArray) || typeEqual(firstType, tomlArrayHash) { + nest := tomlArrayType(eindirect(rv.Index(0))) + if typeEqual(nest, tomlHash) || typeEqual(nest, tomlArrayHash) { + encPanic(errArrayNoTable) + } + } + return firstType +} + +type tagOptions struct { + skip bool // "-" + name string + omitempty bool + omitzero bool +} + +func getOptions(tag reflect.StructTag) tagOptions { + t := tag.Get("toml") + if t == "-" { + return tagOptions{skip: true} + } + var opts tagOptions + parts := strings.Split(t, ",") + opts.name = parts[0] + for _, s := range parts[1:] { + switch s { + case "omitempty": + opts.omitempty = true + case "omitzero": + opts.omitzero = true + } + } + return opts +} + +func isZero(rv reflect.Value) bool { + switch rv.Kind() { + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + return rv.Int() == 0 + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64: + return rv.Uint() == 0 + case reflect.Float32, reflect.Float64: + return rv.Float() == 0.0 + } + return false +} + +func isEmpty(rv reflect.Value) bool { + switch rv.Kind() { + case reflect.Array, reflect.Slice, reflect.Map, reflect.String: + return rv.Len() == 0 + case reflect.Bool: + return !rv.Bool() + } + return false +} + +func (enc *Encoder) newline() { + if enc.hasWritten { + enc.wf("\n") + } +} + +func (enc *Encoder) keyEqElement(key Key, val reflect.Value) { + if len(key) == 0 { + encPanic(errNoKey) + } + panicIfInvalidKey(key) + enc.wf("%s%s = ", enc.indentStr(key), key.maybeQuoted(len(key)-1)) + enc.eElement(val) + enc.newline() +} + +func (enc *Encoder) wf(format string, v ...interface{}) { + if _, err := fmt.Fprintf(enc.w, format, v...); err != nil { + encPanic(err) + } + enc.hasWritten = true +} + +func (enc *Encoder) indentStr(key Key) string { + return strings.Repeat(enc.Indent, len(key)-1) +} + +func encPanic(err error) { + panic(tomlEncodeError{err}) +} + +func eindirect(v reflect.Value) reflect.Value { + switch v.Kind() { + case reflect.Ptr, reflect.Interface: + return eindirect(v.Elem()) + default: + return v + } +} + +func isNil(rv reflect.Value) bool { + switch rv.Kind() { + case reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice: + return rv.IsNil() + default: + return false + } +} + +func panicIfInvalidKey(key Key) { + for _, k := range key { + if len(k) == 0 { + encPanic(e("Key '%s' is not a valid table name. Key names "+ + "cannot be empty.", key.maybeQuotedAll())) + } + } +} + +func isValidKeyName(s string) bool { + return len(s) != 0 +} diff --git a/vendor/github.com/BurntSushi/toml/encoding_types.go b/vendor/github.com/BurntSushi/toml/encoding_types.go new file mode 100644 index 0000000000..d36e1dd600 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/encoding_types.go @@ -0,0 +1,19 @@ +// +build go1.2 + +package toml + +// In order to support Go 1.1, we define our own TextMarshaler and +// TextUnmarshaler types. For Go 1.2+, we just alias them with the +// standard library interfaces. + +import ( + "encoding" +) + +// TextMarshaler is a synonym for encoding.TextMarshaler. It is defined here +// so that Go 1.1 can be supported. +type TextMarshaler encoding.TextMarshaler + +// TextUnmarshaler is a synonym for encoding.TextUnmarshaler. It is defined +// here so that Go 1.1 can be supported. +type TextUnmarshaler encoding.TextUnmarshaler diff --git a/vendor/github.com/BurntSushi/toml/encoding_types_1.1.go b/vendor/github.com/BurntSushi/toml/encoding_types_1.1.go new file mode 100644 index 0000000000..e8d503d046 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/encoding_types_1.1.go @@ -0,0 +1,18 @@ +// +build !go1.2 + +package toml + +// These interfaces were introduced in Go 1.2, so we add them manually when +// compiling for Go 1.1. + +// TextMarshaler is a synonym for encoding.TextMarshaler. It is defined here +// so that Go 1.1 can be supported. +type TextMarshaler interface { + MarshalText() (text []byte, err error) +} + +// TextUnmarshaler is a synonym for encoding.TextUnmarshaler. It is defined +// here so that Go 1.1 can be supported. +type TextUnmarshaler interface { + UnmarshalText(text []byte) error +} diff --git a/vendor/github.com/BurntSushi/toml/lex.go b/vendor/github.com/BurntSushi/toml/lex.go new file mode 100644 index 0000000000..e0a742a887 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/lex.go @@ -0,0 +1,953 @@ +package toml + +import ( + "fmt" + "strings" + "unicode" + "unicode/utf8" +) + +type itemType int + +const ( + itemError itemType = iota + itemNIL // used in the parser to indicate no type + itemEOF + itemText + itemString + itemRawString + itemMultilineString + itemRawMultilineString + itemBool + itemInteger + itemFloat + itemDatetime + itemArray // the start of an array + itemArrayEnd + itemTableStart + itemTableEnd + itemArrayTableStart + itemArrayTableEnd + itemKeyStart + itemCommentStart + itemInlineTableStart + itemInlineTableEnd +) + +const ( + eof = 0 + comma = ',' + tableStart = '[' + tableEnd = ']' + arrayTableStart = '[' + arrayTableEnd = ']' + tableSep = '.' + keySep = '=' + arrayStart = '[' + arrayEnd = ']' + commentStart = '#' + stringStart = '"' + stringEnd = '"' + rawStringStart = '\'' + rawStringEnd = '\'' + inlineTableStart = '{' + inlineTableEnd = '}' +) + +type stateFn func(lx *lexer) stateFn + +type lexer struct { + input string + start int + pos int + line int + state stateFn + items chan item + + // Allow for backing up up to three runes. + // This is necessary because TOML contains 3-rune tokens (""" and '''). + prevWidths [3]int + nprev int // how many of prevWidths are in use + // If we emit an eof, we can still back up, but it is not OK to call + // next again. + atEOF bool + + // A stack of state functions used to maintain context. + // The idea is to reuse parts of the state machine in various places. + // For example, values can appear at the top level or within arbitrarily + // nested arrays. The last state on the stack is used after a value has + // been lexed. Similarly for comments. + stack []stateFn +} + +type item struct { + typ itemType + val string + line int +} + +func (lx *lexer) nextItem() item { + for { + select { + case item := <-lx.items: + return item + default: + lx.state = lx.state(lx) + } + } +} + +func lex(input string) *lexer { + lx := &lexer{ + input: input, + state: lexTop, + line: 1, + items: make(chan item, 10), + stack: make([]stateFn, 0, 10), + } + return lx +} + +func (lx *lexer) push(state stateFn) { + lx.stack = append(lx.stack, state) +} + +func (lx *lexer) pop() stateFn { + if len(lx.stack) == 0 { + return lx.errorf("BUG in lexer: no states to pop") + } + last := lx.stack[len(lx.stack)-1] + lx.stack = lx.stack[0 : len(lx.stack)-1] + return last +} + +func (lx *lexer) current() string { + return lx.input[lx.start:lx.pos] +} + +func (lx *lexer) emit(typ itemType) { + lx.items <- item{typ, lx.current(), lx.line} + lx.start = lx.pos +} + +func (lx *lexer) emitTrim(typ itemType) { + lx.items <- item{typ, strings.TrimSpace(lx.current()), lx.line} + lx.start = lx.pos +} + +func (lx *lexer) next() (r rune) { + if lx.atEOF { + panic("next called after EOF") + } + if lx.pos >= len(lx.input) { + lx.atEOF = true + return eof + } + + if lx.input[lx.pos] == '\n' { + lx.line++ + } + lx.prevWidths[2] = lx.prevWidths[1] + lx.prevWidths[1] = lx.prevWidths[0] + if lx.nprev < 3 { + lx.nprev++ + } + r, w := utf8.DecodeRuneInString(lx.input[lx.pos:]) + lx.prevWidths[0] = w + lx.pos += w + return r +} + +// ignore skips over the pending input before this point. +func (lx *lexer) ignore() { + lx.start = lx.pos +} + +// backup steps back one rune. Can be called only twice between calls to next. +func (lx *lexer) backup() { + if lx.atEOF { + lx.atEOF = false + return + } + if lx.nprev < 1 { + panic("backed up too far") + } + w := lx.prevWidths[0] + lx.prevWidths[0] = lx.prevWidths[1] + lx.prevWidths[1] = lx.prevWidths[2] + lx.nprev-- + lx.pos -= w + if lx.pos < len(lx.input) && lx.input[lx.pos] == '\n' { + lx.line-- + } +} + +// accept consumes the next rune if it's equal to `valid`. +func (lx *lexer) accept(valid rune) bool { + if lx.next() == valid { + return true + } + lx.backup() + return false +} + +// peek returns but does not consume the next rune in the input. +func (lx *lexer) peek() rune { + r := lx.next() + lx.backup() + return r +} + +// skip ignores all input that matches the given predicate. +func (lx *lexer) skip(pred func(rune) bool) { + for { + r := lx.next() + if pred(r) { + continue + } + lx.backup() + lx.ignore() + return + } +} + +// errorf stops all lexing by emitting an error and returning `nil`. +// Note that any value that is a character is escaped if it's a special +// character (newlines, tabs, etc.). +func (lx *lexer) errorf(format string, values ...interface{}) stateFn { + lx.items <- item{ + itemError, + fmt.Sprintf(format, values...), + lx.line, + } + return nil +} + +// lexTop consumes elements at the top level of TOML data. +func lexTop(lx *lexer) stateFn { + r := lx.next() + if isWhitespace(r) || isNL(r) { + return lexSkip(lx, lexTop) + } + switch r { + case commentStart: + lx.push(lexTop) + return lexCommentStart + case tableStart: + return lexTableStart + case eof: + if lx.pos > lx.start { + return lx.errorf("unexpected EOF") + } + lx.emit(itemEOF) + return nil + } + + // At this point, the only valid item can be a key, so we back up + // and let the key lexer do the rest. + lx.backup() + lx.push(lexTopEnd) + return lexKeyStart +} + +// lexTopEnd is entered whenever a top-level item has been consumed. (A value +// or a table.) It must see only whitespace, and will turn back to lexTop +// upon a newline. If it sees EOF, it will quit the lexer successfully. +func lexTopEnd(lx *lexer) stateFn { + r := lx.next() + switch { + case r == commentStart: + // a comment will read to a newline for us. + lx.push(lexTop) + return lexCommentStart + case isWhitespace(r): + return lexTopEnd + case isNL(r): + lx.ignore() + return lexTop + case r == eof: + lx.emit(itemEOF) + return nil + } + return lx.errorf("expected a top-level item to end with a newline, "+ + "comment, or EOF, but got %q instead", r) +} + +// lexTable lexes the beginning of a table. Namely, it makes sure that +// it starts with a character other than '.' and ']'. +// It assumes that '[' has already been consumed. +// It also handles the case that this is an item in an array of tables. +// e.g., '[[name]]'. +func lexTableStart(lx *lexer) stateFn { + if lx.peek() == arrayTableStart { + lx.next() + lx.emit(itemArrayTableStart) + lx.push(lexArrayTableEnd) + } else { + lx.emit(itemTableStart) + lx.push(lexTableEnd) + } + return lexTableNameStart +} + +func lexTableEnd(lx *lexer) stateFn { + lx.emit(itemTableEnd) + return lexTopEnd +} + +func lexArrayTableEnd(lx *lexer) stateFn { + if r := lx.next(); r != arrayTableEnd { + return lx.errorf("expected end of table array name delimiter %q, "+ + "but got %q instead", arrayTableEnd, r) + } + lx.emit(itemArrayTableEnd) + return lexTopEnd +} + +func lexTableNameStart(lx *lexer) stateFn { + lx.skip(isWhitespace) + switch r := lx.peek(); { + case r == tableEnd || r == eof: + return lx.errorf("unexpected end of table name " + + "(table names cannot be empty)") + case r == tableSep: + return lx.errorf("unexpected table separator " + + "(table names cannot be empty)") + case r == stringStart || r == rawStringStart: + lx.ignore() + lx.push(lexTableNameEnd) + return lexValue // reuse string lexing + default: + return lexBareTableName + } +} + +// lexBareTableName lexes the name of a table. It assumes that at least one +// valid character for the table has already been read. +func lexBareTableName(lx *lexer) stateFn { + r := lx.next() + if isBareKeyChar(r) { + return lexBareTableName + } + lx.backup() + lx.emit(itemText) + return lexTableNameEnd +} + +// lexTableNameEnd reads the end of a piece of a table name, optionally +// consuming whitespace. +func lexTableNameEnd(lx *lexer) stateFn { + lx.skip(isWhitespace) + switch r := lx.next(); { + case isWhitespace(r): + return lexTableNameEnd + case r == tableSep: + lx.ignore() + return lexTableNameStart + case r == tableEnd: + return lx.pop() + default: + return lx.errorf("expected '.' or ']' to end table name, "+ + "but got %q instead", r) + } +} + +// lexKeyStart consumes a key name up until the first non-whitespace character. +// lexKeyStart will ignore whitespace. +func lexKeyStart(lx *lexer) stateFn { + r := lx.peek() + switch { + case r == keySep: + return lx.errorf("unexpected key separator %q", keySep) + case isWhitespace(r) || isNL(r): + lx.next() + return lexSkip(lx, lexKeyStart) + case r == stringStart || r == rawStringStart: + lx.ignore() + lx.emit(itemKeyStart) + lx.push(lexKeyEnd) + return lexValue // reuse string lexing + default: + lx.ignore() + lx.emit(itemKeyStart) + return lexBareKey + } +} + +// lexBareKey consumes the text of a bare key. Assumes that the first character +// (which is not whitespace) has not yet been consumed. +func lexBareKey(lx *lexer) stateFn { + switch r := lx.next(); { + case isBareKeyChar(r): + return lexBareKey + case isWhitespace(r): + lx.backup() + lx.emit(itemText) + return lexKeyEnd + case r == keySep: + lx.backup() + lx.emit(itemText) + return lexKeyEnd + default: + return lx.errorf("bare keys cannot contain %q", r) + } +} + +// lexKeyEnd consumes the end of a key and trims whitespace (up to the key +// separator). +func lexKeyEnd(lx *lexer) stateFn { + switch r := lx.next(); { + case r == keySep: + return lexSkip(lx, lexValue) + case isWhitespace(r): + return lexSkip(lx, lexKeyEnd) + default: + return lx.errorf("expected key separator %q, but got %q instead", + keySep, r) + } +} + +// lexValue starts the consumption of a value anywhere a value is expected. +// lexValue will ignore whitespace. +// After a value is lexed, the last state on the next is popped and returned. +func lexValue(lx *lexer) stateFn { + // We allow whitespace to precede a value, but NOT newlines. + // In array syntax, the array states are responsible for ignoring newlines. + r := lx.next() + switch { + case isWhitespace(r): + return lexSkip(lx, lexValue) + case isDigit(r): + lx.backup() // avoid an extra state and use the same as above + return lexNumberOrDateStart + } + switch r { + case arrayStart: + lx.ignore() + lx.emit(itemArray) + return lexArrayValue + case inlineTableStart: + lx.ignore() + lx.emit(itemInlineTableStart) + return lexInlineTableValue + case stringStart: + if lx.accept(stringStart) { + if lx.accept(stringStart) { + lx.ignore() // Ignore """ + return lexMultilineString + } + lx.backup() + } + lx.ignore() // ignore the '"' + return lexString + case rawStringStart: + if lx.accept(rawStringStart) { + if lx.accept(rawStringStart) { + lx.ignore() // Ignore """ + return lexMultilineRawString + } + lx.backup() + } + lx.ignore() // ignore the "'" + return lexRawString + case '+', '-': + return lexNumberStart + case '.': // special error case, be kind to users + return lx.errorf("floats must start with a digit, not '.'") + } + if unicode.IsLetter(r) { + // Be permissive here; lexBool will give a nice error if the + // user wrote something like + // x = foo + // (i.e. not 'true' or 'false' but is something else word-like.) + lx.backup() + return lexBool + } + return lx.errorf("expected value but found %q instead", r) +} + +// lexArrayValue consumes one value in an array. It assumes that '[' or ',' +// have already been consumed. All whitespace and newlines are ignored. +func lexArrayValue(lx *lexer) stateFn { + r := lx.next() + switch { + case isWhitespace(r) || isNL(r): + return lexSkip(lx, lexArrayValue) + case r == commentStart: + lx.push(lexArrayValue) + return lexCommentStart + case r == comma: + return lx.errorf("unexpected comma") + case r == arrayEnd: + // NOTE(caleb): The spec isn't clear about whether you can have + // a trailing comma or not, so we'll allow it. + return lexArrayEnd + } + + lx.backup() + lx.push(lexArrayValueEnd) + return lexValue +} + +// lexArrayValueEnd consumes everything between the end of an array value and +// the next value (or the end of the array): it ignores whitespace and newlines +// and expects either a ',' or a ']'. +func lexArrayValueEnd(lx *lexer) stateFn { + r := lx.next() + switch { + case isWhitespace(r) || isNL(r): + return lexSkip(lx, lexArrayValueEnd) + case r == commentStart: + lx.push(lexArrayValueEnd) + return lexCommentStart + case r == comma: + lx.ignore() + return lexArrayValue // move on to the next value + case r == arrayEnd: + return lexArrayEnd + } + return lx.errorf( + "expected a comma or array terminator %q, but got %q instead", + arrayEnd, r, + ) +} + +// lexArrayEnd finishes the lexing of an array. +// It assumes that a ']' has just been consumed. +func lexArrayEnd(lx *lexer) stateFn { + lx.ignore() + lx.emit(itemArrayEnd) + return lx.pop() +} + +// lexInlineTableValue consumes one key/value pair in an inline table. +// It assumes that '{' or ',' have already been consumed. Whitespace is ignored. +func lexInlineTableValue(lx *lexer) stateFn { + r := lx.next() + switch { + case isWhitespace(r): + return lexSkip(lx, lexInlineTableValue) + case isNL(r): + return lx.errorf("newlines not allowed within inline tables") + case r == commentStart: + lx.push(lexInlineTableValue) + return lexCommentStart + case r == comma: + return lx.errorf("unexpected comma") + case r == inlineTableEnd: + return lexInlineTableEnd + } + lx.backup() + lx.push(lexInlineTableValueEnd) + return lexKeyStart +} + +// lexInlineTableValueEnd consumes everything between the end of an inline table +// key/value pair and the next pair (or the end of the table): +// it ignores whitespace and expects either a ',' or a '}'. +func lexInlineTableValueEnd(lx *lexer) stateFn { + r := lx.next() + switch { + case isWhitespace(r): + return lexSkip(lx, lexInlineTableValueEnd) + case isNL(r): + return lx.errorf("newlines not allowed within inline tables") + case r == commentStart: + lx.push(lexInlineTableValueEnd) + return lexCommentStart + case r == comma: + lx.ignore() + return lexInlineTableValue + case r == inlineTableEnd: + return lexInlineTableEnd + } + return lx.errorf("expected a comma or an inline table terminator %q, "+ + "but got %q instead", inlineTableEnd, r) +} + +// lexInlineTableEnd finishes the lexing of an inline table. +// It assumes that a '}' has just been consumed. +func lexInlineTableEnd(lx *lexer) stateFn { + lx.ignore() + lx.emit(itemInlineTableEnd) + return lx.pop() +} + +// lexString consumes the inner contents of a string. It assumes that the +// beginning '"' has already been consumed and ignored. +func lexString(lx *lexer) stateFn { + r := lx.next() + switch { + case r == eof: + return lx.errorf("unexpected EOF") + case isNL(r): + return lx.errorf("strings cannot contain newlines") + case r == '\\': + lx.push(lexString) + return lexStringEscape + case r == stringEnd: + lx.backup() + lx.emit(itemString) + lx.next() + lx.ignore() + return lx.pop() + } + return lexString +} + +// lexMultilineString consumes the inner contents of a string. It assumes that +// the beginning '"""' has already been consumed and ignored. +func lexMultilineString(lx *lexer) stateFn { + switch lx.next() { + case eof: + return lx.errorf("unexpected EOF") + case '\\': + return lexMultilineStringEscape + case stringEnd: + if lx.accept(stringEnd) { + if lx.accept(stringEnd) { + lx.backup() + lx.backup() + lx.backup() + lx.emit(itemMultilineString) + lx.next() + lx.next() + lx.next() + lx.ignore() + return lx.pop() + } + lx.backup() + } + } + return lexMultilineString +} + +// lexRawString consumes a raw string. Nothing can be escaped in such a string. +// It assumes that the beginning "'" has already been consumed and ignored. +func lexRawString(lx *lexer) stateFn { + r := lx.next() + switch { + case r == eof: + return lx.errorf("unexpected EOF") + case isNL(r): + return lx.errorf("strings cannot contain newlines") + case r == rawStringEnd: + lx.backup() + lx.emit(itemRawString) + lx.next() + lx.ignore() + return lx.pop() + } + return lexRawString +} + +// lexMultilineRawString consumes a raw string. Nothing can be escaped in such +// a string. It assumes that the beginning "'''" has already been consumed and +// ignored. +func lexMultilineRawString(lx *lexer) stateFn { + switch lx.next() { + case eof: + return lx.errorf("unexpected EOF") + case rawStringEnd: + if lx.accept(rawStringEnd) { + if lx.accept(rawStringEnd) { + lx.backup() + lx.backup() + lx.backup() + lx.emit(itemRawMultilineString) + lx.next() + lx.next() + lx.next() + lx.ignore() + return lx.pop() + } + lx.backup() + } + } + return lexMultilineRawString +} + +// lexMultilineStringEscape consumes an escaped character. It assumes that the +// preceding '\\' has already been consumed. +func lexMultilineStringEscape(lx *lexer) stateFn { + // Handle the special case first: + if isNL(lx.next()) { + return lexMultilineString + } + lx.backup() + lx.push(lexMultilineString) + return lexStringEscape(lx) +} + +func lexStringEscape(lx *lexer) stateFn { + r := lx.next() + switch r { + case 'b': + fallthrough + case 't': + fallthrough + case 'n': + fallthrough + case 'f': + fallthrough + case 'r': + fallthrough + case '"': + fallthrough + case '\\': + return lx.pop() + case 'u': + return lexShortUnicodeEscape + case 'U': + return lexLongUnicodeEscape + } + return lx.errorf("invalid escape character %q; only the following "+ + "escape characters are allowed: "+ + `\b, \t, \n, \f, \r, \", \\, \uXXXX, and \UXXXXXXXX`, r) +} + +func lexShortUnicodeEscape(lx *lexer) stateFn { + var r rune + for i := 0; i < 4; i++ { + r = lx.next() + if !isHexadecimal(r) { + return lx.errorf(`expected four hexadecimal digits after '\u', `+ + "but got %q instead", lx.current()) + } + } + return lx.pop() +} + +func lexLongUnicodeEscape(lx *lexer) stateFn { + var r rune + for i := 0; i < 8; i++ { + r = lx.next() + if !isHexadecimal(r) { + return lx.errorf(`expected eight hexadecimal digits after '\U', `+ + "but got %q instead", lx.current()) + } + } + return lx.pop() +} + +// lexNumberOrDateStart consumes either an integer, a float, or datetime. +func lexNumberOrDateStart(lx *lexer) stateFn { + r := lx.next() + if isDigit(r) { + return lexNumberOrDate + } + switch r { + case '_': + return lexNumber + case 'e', 'E': + return lexFloat + case '.': + return lx.errorf("floats must start with a digit, not '.'") + } + return lx.errorf("expected a digit but got %q", r) +} + +// lexNumberOrDate consumes either an integer, float or datetime. +func lexNumberOrDate(lx *lexer) stateFn { + r := lx.next() + if isDigit(r) { + return lexNumberOrDate + } + switch r { + case '-': + return lexDatetime + case '_': + return lexNumber + case '.', 'e', 'E': + return lexFloat + } + + lx.backup() + lx.emit(itemInteger) + return lx.pop() +} + +// lexDatetime consumes a Datetime, to a first approximation. +// The parser validates that it matches one of the accepted formats. +func lexDatetime(lx *lexer) stateFn { + r := lx.next() + if isDigit(r) { + return lexDatetime + } + switch r { + case '-', 'T', ':', '.', 'Z', '+': + return lexDatetime + } + + lx.backup() + lx.emit(itemDatetime) + return lx.pop() +} + +// lexNumberStart consumes either an integer or a float. It assumes that a sign +// has already been read, but that *no* digits have been consumed. +// lexNumberStart will move to the appropriate integer or float states. +func lexNumberStart(lx *lexer) stateFn { + // We MUST see a digit. Even floats have to start with a digit. + r := lx.next() + if !isDigit(r) { + if r == '.' { + return lx.errorf("floats must start with a digit, not '.'") + } + return lx.errorf("expected a digit but got %q", r) + } + return lexNumber +} + +// lexNumber consumes an integer or a float after seeing the first digit. +func lexNumber(lx *lexer) stateFn { + r := lx.next() + if isDigit(r) { + return lexNumber + } + switch r { + case '_': + return lexNumber + case '.', 'e', 'E': + return lexFloat + } + + lx.backup() + lx.emit(itemInteger) + return lx.pop() +} + +// lexFloat consumes the elements of a float. It allows any sequence of +// float-like characters, so floats emitted by the lexer are only a first +// approximation and must be validated by the parser. +func lexFloat(lx *lexer) stateFn { + r := lx.next() + if isDigit(r) { + return lexFloat + } + switch r { + case '_', '.', '-', '+', 'e', 'E': + return lexFloat + } + + lx.backup() + lx.emit(itemFloat) + return lx.pop() +} + +// lexBool consumes a bool string: 'true' or 'false. +func lexBool(lx *lexer) stateFn { + var rs []rune + for { + r := lx.next() + if !unicode.IsLetter(r) { + lx.backup() + break + } + rs = append(rs, r) + } + s := string(rs) + switch s { + case "true", "false": + lx.emit(itemBool) + return lx.pop() + } + return lx.errorf("expected value but found %q instead", s) +} + +// lexCommentStart begins the lexing of a comment. It will emit +// itemCommentStart and consume no characters, passing control to lexComment. +func lexCommentStart(lx *lexer) stateFn { + lx.ignore() + lx.emit(itemCommentStart) + return lexComment +} + +// lexComment lexes an entire comment. It assumes that '#' has been consumed. +// It will consume *up to* the first newline character, and pass control +// back to the last state on the stack. +func lexComment(lx *lexer) stateFn { + r := lx.peek() + if isNL(r) || r == eof { + lx.emit(itemText) + return lx.pop() + } + lx.next() + return lexComment +} + +// lexSkip ignores all slurped input and moves on to the next state. +func lexSkip(lx *lexer, nextState stateFn) stateFn { + return func(lx *lexer) stateFn { + lx.ignore() + return nextState + } +} + +// isWhitespace returns true if `r` is a whitespace character according +// to the spec. +func isWhitespace(r rune) bool { + return r == '\t' || r == ' ' +} + +func isNL(r rune) bool { + return r == '\n' || r == '\r' +} + +func isDigit(r rune) bool { + return r >= '0' && r <= '9' +} + +func isHexadecimal(r rune) bool { + return (r >= '0' && r <= '9') || + (r >= 'a' && r <= 'f') || + (r >= 'A' && r <= 'F') +} + +func isBareKeyChar(r rune) bool { + return (r >= 'A' && r <= 'Z') || + (r >= 'a' && r <= 'z') || + (r >= '0' && r <= '9') || + r == '_' || + r == '-' +} + +func (itype itemType) String() string { + switch itype { + case itemError: + return "Error" + case itemNIL: + return "NIL" + case itemEOF: + return "EOF" + case itemText: + return "Text" + case itemString, itemRawString, itemMultilineString, itemRawMultilineString: + return "String" + case itemBool: + return "Bool" + case itemInteger: + return "Integer" + case itemFloat: + return "Float" + case itemDatetime: + return "DateTime" + case itemTableStart: + return "TableStart" + case itemTableEnd: + return "TableEnd" + case itemKeyStart: + return "KeyStart" + case itemArray: + return "Array" + case itemArrayEnd: + return "ArrayEnd" + case itemCommentStart: + return "CommentStart" + } + panic(fmt.Sprintf("BUG: Unknown type '%d'.", int(itype))) +} + +func (item item) String() string { + return fmt.Sprintf("(%s, %s)", item.typ.String(), item.val) +} diff --git a/vendor/github.com/BurntSushi/toml/parse.go b/vendor/github.com/BurntSushi/toml/parse.go new file mode 100644 index 0000000000..50869ef926 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/parse.go @@ -0,0 +1,592 @@ +package toml + +import ( + "fmt" + "strconv" + "strings" + "time" + "unicode" + "unicode/utf8" +) + +type parser struct { + mapping map[string]interface{} + types map[string]tomlType + lx *lexer + + // A list of keys in the order that they appear in the TOML data. + ordered []Key + + // the full key for the current hash in scope + context Key + + // the base key name for everything except hashes + currentKey string + + // rough approximation of line number + approxLine int + + // A map of 'key.group.names' to whether they were created implicitly. + implicits map[string]bool +} + +type parseError string + +func (pe parseError) Error() string { + return string(pe) +} + +func parse(data string) (p *parser, err error) { + defer func() { + if r := recover(); r != nil { + var ok bool + if err, ok = r.(parseError); ok { + return + } + panic(r) + } + }() + + p = &parser{ + mapping: make(map[string]interface{}), + types: make(map[string]tomlType), + lx: lex(data), + ordered: make([]Key, 0), + implicits: make(map[string]bool), + } + for { + item := p.next() + if item.typ == itemEOF { + break + } + p.topLevel(item) + } + + return p, nil +} + +func (p *parser) panicf(format string, v ...interface{}) { + msg := fmt.Sprintf("Near line %d (last key parsed '%s'): %s", + p.approxLine, p.current(), fmt.Sprintf(format, v...)) + panic(parseError(msg)) +} + +func (p *parser) next() item { + it := p.lx.nextItem() + if it.typ == itemError { + p.panicf("%s", it.val) + } + return it +} + +func (p *parser) bug(format string, v ...interface{}) { + panic(fmt.Sprintf("BUG: "+format+"\n\n", v...)) +} + +func (p *parser) expect(typ itemType) item { + it := p.next() + p.assertEqual(typ, it.typ) + return it +} + +func (p *parser) assertEqual(expected, got itemType) { + if expected != got { + p.bug("Expected '%s' but got '%s'.", expected, got) + } +} + +func (p *parser) topLevel(item item) { + switch item.typ { + case itemCommentStart: + p.approxLine = item.line + p.expect(itemText) + case itemTableStart: + kg := p.next() + p.approxLine = kg.line + + var key Key + for ; kg.typ != itemTableEnd && kg.typ != itemEOF; kg = p.next() { + key = append(key, p.keyString(kg)) + } + p.assertEqual(itemTableEnd, kg.typ) + + p.establishContext(key, false) + p.setType("", tomlHash) + p.ordered = append(p.ordered, key) + case itemArrayTableStart: + kg := p.next() + p.approxLine = kg.line + + var key Key + for ; kg.typ != itemArrayTableEnd && kg.typ != itemEOF; kg = p.next() { + key = append(key, p.keyString(kg)) + } + p.assertEqual(itemArrayTableEnd, kg.typ) + + p.establishContext(key, true) + p.setType("", tomlArrayHash) + p.ordered = append(p.ordered, key) + case itemKeyStart: + kname := p.next() + p.approxLine = kname.line + p.currentKey = p.keyString(kname) + + val, typ := p.value(p.next()) + p.setValue(p.currentKey, val) + p.setType(p.currentKey, typ) + p.ordered = append(p.ordered, p.context.add(p.currentKey)) + p.currentKey = "" + default: + p.bug("Unexpected type at top level: %s", item.typ) + } +} + +// Gets a string for a key (or part of a key in a table name). +func (p *parser) keyString(it item) string { + switch it.typ { + case itemText: + return it.val + case itemString, itemMultilineString, + itemRawString, itemRawMultilineString: + s, _ := p.value(it) + return s.(string) + default: + p.bug("Unexpected key type: %s", it.typ) + panic("unreachable") + } +} + +// value translates an expected value from the lexer into a Go value wrapped +// as an empty interface. +func (p *parser) value(it item) (interface{}, tomlType) { + switch it.typ { + case itemString: + return p.replaceEscapes(it.val), p.typeOfPrimitive(it) + case itemMultilineString: + trimmed := stripFirstNewline(stripEscapedWhitespace(it.val)) + return p.replaceEscapes(trimmed), p.typeOfPrimitive(it) + case itemRawString: + return it.val, p.typeOfPrimitive(it) + case itemRawMultilineString: + return stripFirstNewline(it.val), p.typeOfPrimitive(it) + case itemBool: + switch it.val { + case "true": + return true, p.typeOfPrimitive(it) + case "false": + return false, p.typeOfPrimitive(it) + } + p.bug("Expected boolean value, but got '%s'.", it.val) + case itemInteger: + if !numUnderscoresOK(it.val) { + p.panicf("Invalid integer %q: underscores must be surrounded by digits", + it.val) + } + val := strings.Replace(it.val, "_", "", -1) + num, err := strconv.ParseInt(val, 10, 64) + if err != nil { + // Distinguish integer values. Normally, it'd be a bug if the lexer + // provides an invalid integer, but it's possible that the number is + // out of range of valid values (which the lexer cannot determine). + // So mark the former as a bug but the latter as a legitimate user + // error. + if e, ok := err.(*strconv.NumError); ok && + e.Err == strconv.ErrRange { + + p.panicf("Integer '%s' is out of the range of 64-bit "+ + "signed integers.", it.val) + } else { + p.bug("Expected integer value, but got '%s'.", it.val) + } + } + return num, p.typeOfPrimitive(it) + case itemFloat: + parts := strings.FieldsFunc(it.val, func(r rune) bool { + switch r { + case '.', 'e', 'E': + return true + } + return false + }) + for _, part := range parts { + if !numUnderscoresOK(part) { + p.panicf("Invalid float %q: underscores must be "+ + "surrounded by digits", it.val) + } + } + if !numPeriodsOK(it.val) { + // As a special case, numbers like '123.' or '1.e2', + // which are valid as far as Go/strconv are concerned, + // must be rejected because TOML says that a fractional + // part consists of '.' followed by 1+ digits. + p.panicf("Invalid float %q: '.' must be followed "+ + "by one or more digits", it.val) + } + val := strings.Replace(it.val, "_", "", -1) + num, err := strconv.ParseFloat(val, 64) + if err != nil { + if e, ok := err.(*strconv.NumError); ok && + e.Err == strconv.ErrRange { + + p.panicf("Float '%s' is out of the range of 64-bit "+ + "IEEE-754 floating-point numbers.", it.val) + } else { + p.panicf("Invalid float value: %q", it.val) + } + } + return num, p.typeOfPrimitive(it) + case itemDatetime: + var t time.Time + var ok bool + var err error + for _, format := range []string{ + "2006-01-02T15:04:05Z07:00", + "2006-01-02T15:04:05", + "2006-01-02", + } { + t, err = time.ParseInLocation(format, it.val, time.Local) + if err == nil { + ok = true + break + } + } + if !ok { + p.panicf("Invalid TOML Datetime: %q.", it.val) + } + return t, p.typeOfPrimitive(it) + case itemArray: + array := make([]interface{}, 0) + types := make([]tomlType, 0) + + for it = p.next(); it.typ != itemArrayEnd; it = p.next() { + if it.typ == itemCommentStart { + p.expect(itemText) + continue + } + + val, typ := p.value(it) + array = append(array, val) + types = append(types, typ) + } + return array, p.typeOfArray(types) + case itemInlineTableStart: + var ( + hash = make(map[string]interface{}) + outerContext = p.context + outerKey = p.currentKey + ) + + p.context = append(p.context, p.currentKey) + p.currentKey = "" + for it := p.next(); it.typ != itemInlineTableEnd; it = p.next() { + if it.typ != itemKeyStart { + p.bug("Expected key start but instead found %q, around line %d", + it.val, p.approxLine) + } + if it.typ == itemCommentStart { + p.expect(itemText) + continue + } + + // retrieve key + k := p.next() + p.approxLine = k.line + kname := p.keyString(k) + + // retrieve value + p.currentKey = kname + val, typ := p.value(p.next()) + // make sure we keep metadata up to date + p.setType(kname, typ) + p.ordered = append(p.ordered, p.context.add(p.currentKey)) + hash[kname] = val + } + p.context = outerContext + p.currentKey = outerKey + return hash, tomlHash + } + p.bug("Unexpected value type: %s", it.typ) + panic("unreachable") +} + +// numUnderscoresOK checks whether each underscore in s is surrounded by +// characters that are not underscores. +func numUnderscoresOK(s string) bool { + accept := false + for _, r := range s { + if r == '_' { + if !accept { + return false + } + accept = false + continue + } + accept = true + } + return accept +} + +// numPeriodsOK checks whether every period in s is followed by a digit. +func numPeriodsOK(s string) bool { + period := false + for _, r := range s { + if period && !isDigit(r) { + return false + } + period = r == '.' + } + return !period +} + +// establishContext sets the current context of the parser, +// where the context is either a hash or an array of hashes. Which one is +// set depends on the value of the `array` parameter. +// +// Establishing the context also makes sure that the key isn't a duplicate, and +// will create implicit hashes automatically. +func (p *parser) establishContext(key Key, array bool) { + var ok bool + + // Always start at the top level and drill down for our context. + hashContext := p.mapping + keyContext := make(Key, 0) + + // We only need implicit hashes for key[0:-1] + for _, k := range key[0 : len(key)-1] { + _, ok = hashContext[k] + keyContext = append(keyContext, k) + + // No key? Make an implicit hash and move on. + if !ok { + p.addImplicit(keyContext) + hashContext[k] = make(map[string]interface{}) + } + + // If the hash context is actually an array of tables, then set + // the hash context to the last element in that array. + // + // Otherwise, it better be a table, since this MUST be a key group (by + // virtue of it not being the last element in a key). + switch t := hashContext[k].(type) { + case []map[string]interface{}: + hashContext = t[len(t)-1] + case map[string]interface{}: + hashContext = t + default: + p.panicf("Key '%s' was already created as a hash.", keyContext) + } + } + + p.context = keyContext + if array { + // If this is the first element for this array, then allocate a new + // list of tables for it. + k := key[len(key)-1] + if _, ok := hashContext[k]; !ok { + hashContext[k] = make([]map[string]interface{}, 0, 5) + } + + // Add a new table. But make sure the key hasn't already been used + // for something else. + if hash, ok := hashContext[k].([]map[string]interface{}); ok { + hashContext[k] = append(hash, make(map[string]interface{})) + } else { + p.panicf("Key '%s' was already created and cannot be used as "+ + "an array.", keyContext) + } + } else { + p.setValue(key[len(key)-1], make(map[string]interface{})) + } + p.context = append(p.context, key[len(key)-1]) +} + +// setValue sets the given key to the given value in the current context. +// It will make sure that the key hasn't already been defined, account for +// implicit key groups. +func (p *parser) setValue(key string, value interface{}) { + var tmpHash interface{} + var ok bool + + hash := p.mapping + keyContext := make(Key, 0) + for _, k := range p.context { + keyContext = append(keyContext, k) + if tmpHash, ok = hash[k]; !ok { + p.bug("Context for key '%s' has not been established.", keyContext) + } + switch t := tmpHash.(type) { + case []map[string]interface{}: + // The context is a table of hashes. Pick the most recent table + // defined as the current hash. + hash = t[len(t)-1] + case map[string]interface{}: + hash = t + default: + p.bug("Expected hash to have type 'map[string]interface{}', but "+ + "it has '%T' instead.", tmpHash) + } + } + keyContext = append(keyContext, key) + + if _, ok := hash[key]; ok { + // Typically, if the given key has already been set, then we have + // to raise an error since duplicate keys are disallowed. However, + // it's possible that a key was previously defined implicitly. In this + // case, it is allowed to be redefined concretely. (See the + // `tests/valid/implicit-and-explicit-after.toml` test in `toml-test`.) + // + // But we have to make sure to stop marking it as an implicit. (So that + // another redefinition provokes an error.) + // + // Note that since it has already been defined (as a hash), we don't + // want to overwrite it. So our business is done. + if p.isImplicit(keyContext) { + p.removeImplicit(keyContext) + return + } + + // Otherwise, we have a concrete key trying to override a previous + // key, which is *always* wrong. + p.panicf("Key '%s' has already been defined.", keyContext) + } + hash[key] = value +} + +// setType sets the type of a particular value at a given key. +// It should be called immediately AFTER setValue. +// +// Note that if `key` is empty, then the type given will be applied to the +// current context (which is either a table or an array of tables). +func (p *parser) setType(key string, typ tomlType) { + keyContext := make(Key, 0, len(p.context)+1) + for _, k := range p.context { + keyContext = append(keyContext, k) + } + if len(key) > 0 { // allow type setting for hashes + keyContext = append(keyContext, key) + } + p.types[keyContext.String()] = typ +} + +// addImplicit sets the given Key as having been created implicitly. +func (p *parser) addImplicit(key Key) { + p.implicits[key.String()] = true +} + +// removeImplicit stops tagging the given key as having been implicitly +// created. +func (p *parser) removeImplicit(key Key) { + p.implicits[key.String()] = false +} + +// isImplicit returns true if the key group pointed to by the key was created +// implicitly. +func (p *parser) isImplicit(key Key) bool { + return p.implicits[key.String()] +} + +// current returns the full key name of the current context. +func (p *parser) current() string { + if len(p.currentKey) == 0 { + return p.context.String() + } + if len(p.context) == 0 { + return p.currentKey + } + return fmt.Sprintf("%s.%s", p.context, p.currentKey) +} + +func stripFirstNewline(s string) string { + if len(s) == 0 || s[0] != '\n' { + return s + } + return s[1:] +} + +func stripEscapedWhitespace(s string) string { + esc := strings.Split(s, "\\\n") + if len(esc) > 1 { + for i := 1; i < len(esc); i++ { + esc[i] = strings.TrimLeftFunc(esc[i], unicode.IsSpace) + } + } + return strings.Join(esc, "") +} + +func (p *parser) replaceEscapes(str string) string { + var replaced []rune + s := []byte(str) + r := 0 + for r < len(s) { + if s[r] != '\\' { + c, size := utf8.DecodeRune(s[r:]) + r += size + replaced = append(replaced, c) + continue + } + r += 1 + if r >= len(s) { + p.bug("Escape sequence at end of string.") + return "" + } + switch s[r] { + default: + p.bug("Expected valid escape code after \\, but got %q.", s[r]) + return "" + case 'b': + replaced = append(replaced, rune(0x0008)) + r += 1 + case 't': + replaced = append(replaced, rune(0x0009)) + r += 1 + case 'n': + replaced = append(replaced, rune(0x000A)) + r += 1 + case 'f': + replaced = append(replaced, rune(0x000C)) + r += 1 + case 'r': + replaced = append(replaced, rune(0x000D)) + r += 1 + case '"': + replaced = append(replaced, rune(0x0022)) + r += 1 + case '\\': + replaced = append(replaced, rune(0x005C)) + r += 1 + case 'u': + // At this point, we know we have a Unicode escape of the form + // `uXXXX` at [r, r+5). (Because the lexer guarantees this + // for us.) + escaped := p.asciiEscapeToUnicode(s[r+1 : r+5]) + replaced = append(replaced, escaped) + r += 5 + case 'U': + // At this point, we know we have a Unicode escape of the form + // `uXXXX` at [r, r+9). (Because the lexer guarantees this + // for us.) + escaped := p.asciiEscapeToUnicode(s[r+1 : r+9]) + replaced = append(replaced, escaped) + r += 9 + } + } + return string(replaced) +} + +func (p *parser) asciiEscapeToUnicode(bs []byte) rune { + s := string(bs) + hex, err := strconv.ParseUint(strings.ToLower(s), 16, 32) + if err != nil { + p.bug("Could not parse '%s' as a hexadecimal number, but the "+ + "lexer claims it's OK: %s", s, err) + } + if !utf8.ValidRune(rune(hex)) { + p.panicf("Escaped character '\\u%s' is not valid UTF-8.", s) + } + return rune(hex) +} + +func isStringType(ty itemType) bool { + return ty == itemString || ty == itemMultilineString || + ty == itemRawString || ty == itemRawMultilineString +} diff --git a/vendor/github.com/BurntSushi/toml/session.vim b/vendor/github.com/BurntSushi/toml/session.vim new file mode 100644 index 0000000000..562164be06 --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/session.vim @@ -0,0 +1 @@ +au BufWritePost *.go silent!make tags > /dev/null 2>&1 diff --git a/vendor/github.com/BurntSushi/toml/type_check.go b/vendor/github.com/BurntSushi/toml/type_check.go new file mode 100644 index 0000000000..c73f8afc1a --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/type_check.go @@ -0,0 +1,91 @@ +package toml + +// tomlType represents any Go type that corresponds to a TOML type. +// While the first draft of the TOML spec has a simplistic type system that +// probably doesn't need this level of sophistication, we seem to be militating +// toward adding real composite types. +type tomlType interface { + typeString() string +} + +// typeEqual accepts any two types and returns true if they are equal. +func typeEqual(t1, t2 tomlType) bool { + if t1 == nil || t2 == nil { + return false + } + return t1.typeString() == t2.typeString() +} + +func typeIsHash(t tomlType) bool { + return typeEqual(t, tomlHash) || typeEqual(t, tomlArrayHash) +} + +type tomlBaseType string + +func (btype tomlBaseType) typeString() string { + return string(btype) +} + +func (btype tomlBaseType) String() string { + return btype.typeString() +} + +var ( + tomlInteger tomlBaseType = "Integer" + tomlFloat tomlBaseType = "Float" + tomlDatetime tomlBaseType = "Datetime" + tomlString tomlBaseType = "String" + tomlBool tomlBaseType = "Bool" + tomlArray tomlBaseType = "Array" + tomlHash tomlBaseType = "Hash" + tomlArrayHash tomlBaseType = "ArrayHash" +) + +// typeOfPrimitive returns a tomlType of any primitive value in TOML. +// Primitive values are: Integer, Float, Datetime, String and Bool. +// +// Passing a lexer item other than the following will cause a BUG message +// to occur: itemString, itemBool, itemInteger, itemFloat, itemDatetime. +func (p *parser) typeOfPrimitive(lexItem item) tomlType { + switch lexItem.typ { + case itemInteger: + return tomlInteger + case itemFloat: + return tomlFloat + case itemDatetime: + return tomlDatetime + case itemString: + return tomlString + case itemMultilineString: + return tomlString + case itemRawString: + return tomlString + case itemRawMultilineString: + return tomlString + case itemBool: + return tomlBool + } + p.bug("Cannot infer primitive type of lex item '%s'.", lexItem) + panic("unreachable") +} + +// typeOfArray returns a tomlType for an array given a list of types of its +// values. +// +// In the current spec, if an array is homogeneous, then its type is always +// "Array". If the array is not homogeneous, an error is generated. +func (p *parser) typeOfArray(types []tomlType) tomlType { + // Empty arrays are cool. + if len(types) == 0 { + return tomlArray + } + + theType := types[0] + for _, t := range types[1:] { + if !typeEqual(theType, t) { + p.panicf("Array contains values of type '%s' and '%s', but "+ + "arrays must be homogeneous.", theType, t) + } + } + return tomlArray +} diff --git a/vendor/github.com/BurntSushi/toml/type_fields.go b/vendor/github.com/BurntSushi/toml/type_fields.go new file mode 100644 index 0000000000..608997c22f --- /dev/null +++ b/vendor/github.com/BurntSushi/toml/type_fields.go @@ -0,0 +1,242 @@ +package toml + +// Struct field handling is adapted from code in encoding/json: +// +// Copyright 2010 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the Go distribution. + +import ( + "reflect" + "sort" + "sync" +) + +// A field represents a single field found in a struct. +type field struct { + name string // the name of the field (`toml` tag included) + tag bool // whether field has a `toml` tag + index []int // represents the depth of an anonymous field + typ reflect.Type // the type of the field +} + +// byName sorts field by name, breaking ties with depth, +// then breaking ties with "name came from toml tag", then +// breaking ties with index sequence. +type byName []field + +func (x byName) Len() int { return len(x) } + +func (x byName) Swap(i, j int) { x[i], x[j] = x[j], x[i] } + +func (x byName) Less(i, j int) bool { + if x[i].name != x[j].name { + return x[i].name < x[j].name + } + if len(x[i].index) != len(x[j].index) { + return len(x[i].index) < len(x[j].index) + } + if x[i].tag != x[j].tag { + return x[i].tag + } + return byIndex(x).Less(i, j) +} + +// byIndex sorts field by index sequence. +type byIndex []field + +func (x byIndex) Len() int { return len(x) } + +func (x byIndex) Swap(i, j int) { x[i], x[j] = x[j], x[i] } + +func (x byIndex) Less(i, j int) bool { + for k, xik := range x[i].index { + if k >= len(x[j].index) { + return false + } + if xik != x[j].index[k] { + return xik < x[j].index[k] + } + } + return len(x[i].index) < len(x[j].index) +} + +// typeFields returns a list of fields that TOML should recognize for the given +// type. The algorithm is breadth-first search over the set of structs to +// include - the top struct and then any reachable anonymous structs. +func typeFields(t reflect.Type) []field { + // Anonymous fields to explore at the current level and the next. + current := []field{} + next := []field{{typ: t}} + + // Count of queued names for current level and the next. + count := map[reflect.Type]int{} + nextCount := map[reflect.Type]int{} + + // Types already visited at an earlier level. + visited := map[reflect.Type]bool{} + + // Fields found. + var fields []field + + for len(next) > 0 { + current, next = next, current[:0] + count, nextCount = nextCount, map[reflect.Type]int{} + + for _, f := range current { + if visited[f.typ] { + continue + } + visited[f.typ] = true + + // Scan f.typ for fields to include. + for i := 0; i < f.typ.NumField(); i++ { + sf := f.typ.Field(i) + if sf.PkgPath != "" && !sf.Anonymous { // unexported + continue + } + opts := getOptions(sf.Tag) + if opts.skip { + continue + } + index := make([]int, len(f.index)+1) + copy(index, f.index) + index[len(f.index)] = i + + ft := sf.Type + if ft.Name() == "" && ft.Kind() == reflect.Ptr { + // Follow pointer. + ft = ft.Elem() + } + + // Record found field and index sequence. + if opts.name != "" || !sf.Anonymous || ft.Kind() != reflect.Struct { + tagged := opts.name != "" + name := opts.name + if name == "" { + name = sf.Name + } + fields = append(fields, field{name, tagged, index, ft}) + if count[f.typ] > 1 { + // If there were multiple instances, add a second, + // so that the annihilation code will see a duplicate. + // It only cares about the distinction between 1 or 2, + // so don't bother generating any more copies. + fields = append(fields, fields[len(fields)-1]) + } + continue + } + + // Record new anonymous struct to explore in next round. + nextCount[ft]++ + if nextCount[ft] == 1 { + f := field{name: ft.Name(), index: index, typ: ft} + next = append(next, f) + } + } + } + } + + sort.Sort(byName(fields)) + + // Delete all fields that are hidden by the Go rules for embedded fields, + // except that fields with TOML tags are promoted. + + // The fields are sorted in primary order of name, secondary order + // of field index length. Loop over names; for each name, delete + // hidden fields by choosing the one dominant field that survives. + out := fields[:0] + for advance, i := 0, 0; i < len(fields); i += advance { + // One iteration per name. + // Find the sequence of fields with the name of this first field. + fi := fields[i] + name := fi.name + for advance = 1; i+advance < len(fields); advance++ { + fj := fields[i+advance] + if fj.name != name { + break + } + } + if advance == 1 { // Only one field with this name + out = append(out, fi) + continue + } + dominant, ok := dominantField(fields[i : i+advance]) + if ok { + out = append(out, dominant) + } + } + + fields = out + sort.Sort(byIndex(fields)) + + return fields +} + +// dominantField looks through the fields, all of which are known to +// have the same name, to find the single field that dominates the +// others using Go's embedding rules, modified by the presence of +// TOML tags. If there are multiple top-level fields, the boolean +// will be false: This condition is an error in Go and we skip all +// the fields. +func dominantField(fields []field) (field, bool) { + // The fields are sorted in increasing index-length order. The winner + // must therefore be one with the shortest index length. Drop all + // longer entries, which is easy: just truncate the slice. + length := len(fields[0].index) + tagged := -1 // Index of first tagged field. + for i, f := range fields { + if len(f.index) > length { + fields = fields[:i] + break + } + if f.tag { + if tagged >= 0 { + // Multiple tagged fields at the same level: conflict. + // Return no field. + return field{}, false + } + tagged = i + } + } + if tagged >= 0 { + return fields[tagged], true + } + // All remaining fields have the same length. If there's more than one, + // we have a conflict (two fields named "X" at the same level) and we + // return no field. + if len(fields) > 1 { + return field{}, false + } + return fields[0], true +} + +var fieldCache struct { + sync.RWMutex + m map[reflect.Type][]field +} + +// cachedTypeFields is like typeFields but uses a cache to avoid repeated work. +func cachedTypeFields(t reflect.Type) []field { + fieldCache.RLock() + f := fieldCache.m[t] + fieldCache.RUnlock() + if f != nil { + return f + } + + // Compute fields without lock. + // Might duplicate effort but won't hold other computations back. + f = typeFields(t) + if f == nil { + f = []field{} + } + + fieldCache.Lock() + if fieldCache.m == nil { + fieldCache.m = map[reflect.Type][]field{} + } + fieldCache.m[t] = f + fieldCache.Unlock() + return f +} diff --git a/vendor/golang.org/x/tools/AUTHORS b/vendor/golang.org/x/tools/AUTHORS new file mode 100644 index 0000000000..15167cd746 --- /dev/null +++ b/vendor/golang.org/x/tools/AUTHORS @@ -0,0 +1,3 @@ +# This source code refers to The Go Authors for copyright purposes. +# The master list of authors is in the main Go distribution, +# visible at http://tip.golang.org/AUTHORS. diff --git a/vendor/golang.org/x/tools/CONTRIBUTORS b/vendor/golang.org/x/tools/CONTRIBUTORS new file mode 100644 index 0000000000..1c4577e968 --- /dev/null +++ b/vendor/golang.org/x/tools/CONTRIBUTORS @@ -0,0 +1,3 @@ +# This source code was written by the Go contributors. +# The master list of contributors is in the main Go distribution, +# visible at http://tip.golang.org/CONTRIBUTORS. diff --git a/vendor/golang.org/x/tools/LICENSE b/vendor/golang.org/x/tools/LICENSE new file mode 100644 index 0000000000..6a66aea5ea --- /dev/null +++ b/vendor/golang.org/x/tools/LICENSE @@ -0,0 +1,27 @@ +Copyright (c) 2009 The Go Authors. All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + * Redistributions of source code must retain the above copyright +notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above +copyright notice, this list of conditions and the following disclaimer +in the documentation and/or other materials provided with the +distribution. + * Neither the name of Google Inc. nor the names of its +contributors may be used to endorse or promote products derived from +this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/vendor/golang.org/x/tools/PATENTS b/vendor/golang.org/x/tools/PATENTS new file mode 100644 index 0000000000..733099041f --- /dev/null +++ b/vendor/golang.org/x/tools/PATENTS @@ -0,0 +1,22 @@ +Additional IP Rights Grant (Patents) + +"This implementation" means the copyrightable works distributed by +Google as part of the Go project. + +Google hereby grants to You a perpetual, worldwide, non-exclusive, +no-charge, royalty-free, irrevocable (except as stated in this section) +patent license to make, have made, use, offer to sell, sell, import, +transfer and otherwise run, modify and propagate the contents of this +implementation of Go, where such license applies only to those patent +claims, both currently owned or controlled by Google and acquired in +the future, licensable by Google that are necessarily infringed by this +implementation of Go. This grant does not include claims that would be +infringed only as a consequence of further modification of this +implementation. If you or your agent or exclusive licensee institute or +order or agree to the institution of patent litigation against any +entity (including a cross-claim or counterclaim in a lawsuit) alleging +that this implementation of Go or any code incorporated within this +implementation of Go constitutes direct or contributory patent +infringement, or inducement of patent infringement, then any patent +rights granted to you under this License for this implementation of Go +shall terminate as of the date such litigation is filed. diff --git a/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go b/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go new file mode 100644 index 0000000000..6b7052b892 --- /dev/null +++ b/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go @@ -0,0 +1,627 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package astutil + +// This file defines utilities for working with source positions. + +import ( + "fmt" + "go/ast" + "go/token" + "sort" +) + +// PathEnclosingInterval returns the node that encloses the source +// interval [start, end), and all its ancestors up to the AST root. +// +// The definition of "enclosing" used by this function considers +// additional whitespace abutting a node to be enclosed by it. +// In this example: +// +// z := x + y // add them +// <-A-> +// <----B-----> +// +// the ast.BinaryExpr(+) node is considered to enclose interval B +// even though its [Pos()..End()) is actually only interval A. +// This behaviour makes user interfaces more tolerant of imperfect +// input. +// +// This function treats tokens as nodes, though they are not included +// in the result. e.g. PathEnclosingInterval("+") returns the +// enclosing ast.BinaryExpr("x + y"). +// +// If start==end, the 1-char interval following start is used instead. +// +// The 'exact' result is true if the interval contains only path[0] +// and perhaps some adjacent whitespace. It is false if the interval +// overlaps multiple children of path[0], or if it contains only +// interior whitespace of path[0]. +// In this example: +// +// z := x + y // add them +// <--C--> <---E--> +// ^ +// D +// +// intervals C, D and E are inexact. C is contained by the +// z-assignment statement, because it spans three of its children (:=, +// x, +). So too is the 1-char interval D, because it contains only +// interior whitespace of the assignment. E is considered interior +// whitespace of the BlockStmt containing the assignment. +// +// Precondition: [start, end) both lie within the same file as root. +// TODO(adonovan): return (nil, false) in this case and remove precond. +// Requires FileSet; see loader.tokenFileContainsPos. +// +// Postcondition: path is never nil; it always contains at least 'root'. +// +func PathEnclosingInterval(root *ast.File, start, end token.Pos) (path []ast.Node, exact bool) { + // fmt.Printf("EnclosingInterval %d %d\n", start, end) // debugging + + // Precondition: node.[Pos..End) and adjoining whitespace contain [start, end). + var visit func(node ast.Node) bool + visit = func(node ast.Node) bool { + path = append(path, node) + + nodePos := node.Pos() + nodeEnd := node.End() + + // fmt.Printf("visit(%T, %d, %d)\n", node, nodePos, nodeEnd) // debugging + + // Intersect [start, end) with interval of node. + if start < nodePos { + start = nodePos + } + if end > nodeEnd { + end = nodeEnd + } + + // Find sole child that contains [start, end). + children := childrenOf(node) + l := len(children) + for i, child := range children { + // [childPos, childEnd) is unaugmented interval of child. + childPos := child.Pos() + childEnd := child.End() + + // [augPos, augEnd) is whitespace-augmented interval of child. + augPos := childPos + augEnd := childEnd + if i > 0 { + augPos = children[i-1].End() // start of preceding whitespace + } + if i < l-1 { + nextChildPos := children[i+1].Pos() + // Does [start, end) lie between child and next child? + if start >= augEnd && end <= nextChildPos { + return false // inexact match + } + augEnd = nextChildPos // end of following whitespace + } + + // fmt.Printf("\tchild %d: [%d..%d)\tcontains interval [%d..%d)?\n", + // i, augPos, augEnd, start, end) // debugging + + // Does augmented child strictly contain [start, end)? + if augPos <= start && end <= augEnd { + _, isToken := child.(tokenNode) + return isToken || visit(child) + } + + // Does [start, end) overlap multiple children? + // i.e. left-augmented child contains start + // but LR-augmented child does not contain end. + if start < childEnd && end > augEnd { + break + } + } + + // No single child contained [start, end), + // so node is the result. Is it exact? + + // (It's tempting to put this condition before the + // child loop, but it gives the wrong result in the + // case where a node (e.g. ExprStmt) and its sole + // child have equal intervals.) + if start == nodePos && end == nodeEnd { + return true // exact match + } + + return false // inexact: overlaps multiple children + } + + if start > end { + start, end = end, start + } + + if start < root.End() && end > root.Pos() { + if start == end { + end = start + 1 // empty interval => interval of size 1 + } + exact = visit(root) + + // Reverse the path: + for i, l := 0, len(path); i < l/2; i++ { + path[i], path[l-1-i] = path[l-1-i], path[i] + } + } else { + // Selection lies within whitespace preceding the + // first (or following the last) declaration in the file. + // The result nonetheless always includes the ast.File. + path = append(path, root) + } + + return +} + +// tokenNode is a dummy implementation of ast.Node for a single token. +// They are used transiently by PathEnclosingInterval but never escape +// this package. +// +type tokenNode struct { + pos token.Pos + end token.Pos +} + +func (n tokenNode) Pos() token.Pos { + return n.pos +} + +func (n tokenNode) End() token.Pos { + return n.end +} + +func tok(pos token.Pos, len int) ast.Node { + return tokenNode{pos, pos + token.Pos(len)} +} + +// childrenOf returns the direct non-nil children of ast.Node n. +// It may include fake ast.Node implementations for bare tokens. +// it is not safe to call (e.g.) ast.Walk on such nodes. +// +func childrenOf(n ast.Node) []ast.Node { + var children []ast.Node + + // First add nodes for all true subtrees. + ast.Inspect(n, func(node ast.Node) bool { + if node == n { // push n + return true // recur + } + if node != nil { // push child + children = append(children, node) + } + return false // no recursion + }) + + // Then add fake Nodes for bare tokens. + switch n := n.(type) { + case *ast.ArrayType: + children = append(children, + tok(n.Lbrack, len("[")), + tok(n.Elt.End(), len("]"))) + + case *ast.AssignStmt: + children = append(children, + tok(n.TokPos, len(n.Tok.String()))) + + case *ast.BasicLit: + children = append(children, + tok(n.ValuePos, len(n.Value))) + + case *ast.BinaryExpr: + children = append(children, tok(n.OpPos, len(n.Op.String()))) + + case *ast.BlockStmt: + children = append(children, + tok(n.Lbrace, len("{")), + tok(n.Rbrace, len("}"))) + + case *ast.BranchStmt: + children = append(children, + tok(n.TokPos, len(n.Tok.String()))) + + case *ast.CallExpr: + children = append(children, + tok(n.Lparen, len("(")), + tok(n.Rparen, len(")"))) + if n.Ellipsis != 0 { + children = append(children, tok(n.Ellipsis, len("..."))) + } + + case *ast.CaseClause: + if n.List == nil { + children = append(children, + tok(n.Case, len("default"))) + } else { + children = append(children, + tok(n.Case, len("case"))) + } + children = append(children, tok(n.Colon, len(":"))) + + case *ast.ChanType: + switch n.Dir { + case ast.RECV: + children = append(children, tok(n.Begin, len("<-chan"))) + case ast.SEND: + children = append(children, tok(n.Begin, len("chan<-"))) + case ast.RECV | ast.SEND: + children = append(children, tok(n.Begin, len("chan"))) + } + + case *ast.CommClause: + if n.Comm == nil { + children = append(children, + tok(n.Case, len("default"))) + } else { + children = append(children, + tok(n.Case, len("case"))) + } + children = append(children, tok(n.Colon, len(":"))) + + case *ast.Comment: + // nop + + case *ast.CommentGroup: + // nop + + case *ast.CompositeLit: + children = append(children, + tok(n.Lbrace, len("{")), + tok(n.Rbrace, len("{"))) + + case *ast.DeclStmt: + // nop + + case *ast.DeferStmt: + children = append(children, + tok(n.Defer, len("defer"))) + + case *ast.Ellipsis: + children = append(children, + tok(n.Ellipsis, len("..."))) + + case *ast.EmptyStmt: + // nop + + case *ast.ExprStmt: + // nop + + case *ast.Field: + // TODO(adonovan): Field.{Doc,Comment,Tag}? + + case *ast.FieldList: + children = append(children, + tok(n.Opening, len("(")), + tok(n.Closing, len(")"))) + + case *ast.File: + // TODO test: Doc + children = append(children, + tok(n.Package, len("package"))) + + case *ast.ForStmt: + children = append(children, + tok(n.For, len("for"))) + + case *ast.FuncDecl: + // TODO(adonovan): FuncDecl.Comment? + + // Uniquely, FuncDecl breaks the invariant that + // preorder traversal yields tokens in lexical order: + // in fact, FuncDecl.Recv precedes FuncDecl.Type.Func. + // + // As a workaround, we inline the case for FuncType + // here and order things correctly. + // + children = nil // discard ast.Walk(FuncDecl) info subtrees + children = append(children, tok(n.Type.Func, len("func"))) + if n.Recv != nil { + children = append(children, n.Recv) + } + children = append(children, n.Name) + if n.Type.Params != nil { + children = append(children, n.Type.Params) + } + if n.Type.Results != nil { + children = append(children, n.Type.Results) + } + if n.Body != nil { + children = append(children, n.Body) + } + + case *ast.FuncLit: + // nop + + case *ast.FuncType: + if n.Func != 0 { + children = append(children, + tok(n.Func, len("func"))) + } + + case *ast.GenDecl: + children = append(children, + tok(n.TokPos, len(n.Tok.String()))) + if n.Lparen != 0 { + children = append(children, + tok(n.Lparen, len("(")), + tok(n.Rparen, len(")"))) + } + + case *ast.GoStmt: + children = append(children, + tok(n.Go, len("go"))) + + case *ast.Ident: + children = append(children, + tok(n.NamePos, len(n.Name))) + + case *ast.IfStmt: + children = append(children, + tok(n.If, len("if"))) + + case *ast.ImportSpec: + // TODO(adonovan): ImportSpec.{Doc,EndPos}? + + case *ast.IncDecStmt: + children = append(children, + tok(n.TokPos, len(n.Tok.String()))) + + case *ast.IndexExpr: + children = append(children, + tok(n.Lbrack, len("{")), + tok(n.Rbrack, len("}"))) + + case *ast.InterfaceType: + children = append(children, + tok(n.Interface, len("interface"))) + + case *ast.KeyValueExpr: + children = append(children, + tok(n.Colon, len(":"))) + + case *ast.LabeledStmt: + children = append(children, + tok(n.Colon, len(":"))) + + case *ast.MapType: + children = append(children, + tok(n.Map, len("map"))) + + case *ast.ParenExpr: + children = append(children, + tok(n.Lparen, len("(")), + tok(n.Rparen, len(")"))) + + case *ast.RangeStmt: + children = append(children, + tok(n.For, len("for")), + tok(n.TokPos, len(n.Tok.String()))) + + case *ast.ReturnStmt: + children = append(children, + tok(n.Return, len("return"))) + + case *ast.SelectStmt: + children = append(children, + tok(n.Select, len("select"))) + + case *ast.SelectorExpr: + // nop + + case *ast.SendStmt: + children = append(children, + tok(n.Arrow, len("<-"))) + + case *ast.SliceExpr: + children = append(children, + tok(n.Lbrack, len("[")), + tok(n.Rbrack, len("]"))) + + case *ast.StarExpr: + children = append(children, tok(n.Star, len("*"))) + + case *ast.StructType: + children = append(children, tok(n.Struct, len("struct"))) + + case *ast.SwitchStmt: + children = append(children, tok(n.Switch, len("switch"))) + + case *ast.TypeAssertExpr: + children = append(children, + tok(n.Lparen-1, len(".")), + tok(n.Lparen, len("(")), + tok(n.Rparen, len(")"))) + + case *ast.TypeSpec: + // TODO(adonovan): TypeSpec.{Doc,Comment}? + + case *ast.TypeSwitchStmt: + children = append(children, tok(n.Switch, len("switch"))) + + case *ast.UnaryExpr: + children = append(children, tok(n.OpPos, len(n.Op.String()))) + + case *ast.ValueSpec: + // TODO(adonovan): ValueSpec.{Doc,Comment}? + + case *ast.BadDecl, *ast.BadExpr, *ast.BadStmt: + // nop + } + + // TODO(adonovan): opt: merge the logic of ast.Inspect() into + // the switch above so we can make interleaved callbacks for + // both Nodes and Tokens in the right order and avoid the need + // to sort. + sort.Sort(byPos(children)) + + return children +} + +type byPos []ast.Node + +func (sl byPos) Len() int { + return len(sl) +} +func (sl byPos) Less(i, j int) bool { + return sl[i].Pos() < sl[j].Pos() +} +func (sl byPos) Swap(i, j int) { + sl[i], sl[j] = sl[j], sl[i] +} + +// NodeDescription returns a description of the concrete type of n suitable +// for a user interface. +// +// TODO(adonovan): in some cases (e.g. Field, FieldList, Ident, +// StarExpr) we could be much more specific given the path to the AST +// root. Perhaps we should do that. +// +func NodeDescription(n ast.Node) string { + switch n := n.(type) { + case *ast.ArrayType: + return "array type" + case *ast.AssignStmt: + return "assignment" + case *ast.BadDecl: + return "bad declaration" + case *ast.BadExpr: + return "bad expression" + case *ast.BadStmt: + return "bad statement" + case *ast.BasicLit: + return "basic literal" + case *ast.BinaryExpr: + return fmt.Sprintf("binary %s operation", n.Op) + case *ast.BlockStmt: + return "block" + case *ast.BranchStmt: + switch n.Tok { + case token.BREAK: + return "break statement" + case token.CONTINUE: + return "continue statement" + case token.GOTO: + return "goto statement" + case token.FALLTHROUGH: + return "fall-through statement" + } + case *ast.CallExpr: + if len(n.Args) == 1 && !n.Ellipsis.IsValid() { + return "function call (or conversion)" + } + return "function call" + case *ast.CaseClause: + return "case clause" + case *ast.ChanType: + return "channel type" + case *ast.CommClause: + return "communication clause" + case *ast.Comment: + return "comment" + case *ast.CommentGroup: + return "comment group" + case *ast.CompositeLit: + return "composite literal" + case *ast.DeclStmt: + return NodeDescription(n.Decl) + " statement" + case *ast.DeferStmt: + return "defer statement" + case *ast.Ellipsis: + return "ellipsis" + case *ast.EmptyStmt: + return "empty statement" + case *ast.ExprStmt: + return "expression statement" + case *ast.Field: + // Can be any of these: + // struct {x, y int} -- struct field(s) + // struct {T} -- anon struct field + // interface {I} -- interface embedding + // interface {f()} -- interface method + // func (A) func(B) C -- receiver, param(s), result(s) + return "field/method/parameter" + case *ast.FieldList: + return "field/method/parameter list" + case *ast.File: + return "source file" + case *ast.ForStmt: + return "for loop" + case *ast.FuncDecl: + return "function declaration" + case *ast.FuncLit: + return "function literal" + case *ast.FuncType: + return "function type" + case *ast.GenDecl: + switch n.Tok { + case token.IMPORT: + return "import declaration" + case token.CONST: + return "constant declaration" + case token.TYPE: + return "type declaration" + case token.VAR: + return "variable declaration" + } + case *ast.GoStmt: + return "go statement" + case *ast.Ident: + return "identifier" + case *ast.IfStmt: + return "if statement" + case *ast.ImportSpec: + return "import specification" + case *ast.IncDecStmt: + if n.Tok == token.INC { + return "increment statement" + } + return "decrement statement" + case *ast.IndexExpr: + return "index expression" + case *ast.InterfaceType: + return "interface type" + case *ast.KeyValueExpr: + return "key/value association" + case *ast.LabeledStmt: + return "statement label" + case *ast.MapType: + return "map type" + case *ast.Package: + return "package" + case *ast.ParenExpr: + return "parenthesized " + NodeDescription(n.X) + case *ast.RangeStmt: + return "range loop" + case *ast.ReturnStmt: + return "return statement" + case *ast.SelectStmt: + return "select statement" + case *ast.SelectorExpr: + return "selector" + case *ast.SendStmt: + return "channel send" + case *ast.SliceExpr: + return "slice expression" + case *ast.StarExpr: + return "*-operation" // load/store expr or pointer type + case *ast.StructType: + return "struct type" + case *ast.SwitchStmt: + return "switch statement" + case *ast.TypeAssertExpr: + return "type assertion" + case *ast.TypeSpec: + return "type specification" + case *ast.TypeSwitchStmt: + return "type switch" + case *ast.UnaryExpr: + return fmt.Sprintf("unary %s operation", n.Op) + case *ast.ValueSpec: + return "value specification" + + } + panic(fmt.Sprintf("unexpected node type: %T", n)) +} diff --git a/vendor/golang.org/x/tools/go/ast/astutil/imports.go b/vendor/golang.org/x/tools/go/ast/astutil/imports.go new file mode 100644 index 0000000000..04ad6795d9 --- /dev/null +++ b/vendor/golang.org/x/tools/go/ast/astutil/imports.go @@ -0,0 +1,471 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package astutil contains common utilities for working with the Go AST. +package astutil // import "golang.org/x/tools/go/ast/astutil" + +import ( + "fmt" + "go/ast" + "go/token" + "strconv" + "strings" +) + +// AddImport adds the import path to the file f, if absent. +func AddImport(fset *token.FileSet, f *ast.File, ipath string) (added bool) { + return AddNamedImport(fset, f, "", ipath) +} + +// AddNamedImport adds the import path to the file f, if absent. +// If name is not empty, it is used to rename the import. +// +// For example, calling +// AddNamedImport(fset, f, "pathpkg", "path") +// adds +// import pathpkg "path" +func AddNamedImport(fset *token.FileSet, f *ast.File, name, ipath string) (added bool) { + if imports(f, ipath) { + return false + } + + newImport := &ast.ImportSpec{ + Path: &ast.BasicLit{ + Kind: token.STRING, + Value: strconv.Quote(ipath), + }, + } + if name != "" { + newImport.Name = &ast.Ident{Name: name} + } + + // Find an import decl to add to. + // The goal is to find an existing import + // whose import path has the longest shared + // prefix with ipath. + var ( + bestMatch = -1 // length of longest shared prefix + lastImport = -1 // index in f.Decls of the file's final import decl + impDecl *ast.GenDecl // import decl containing the best match + impIndex = -1 // spec index in impDecl containing the best match + + isThirdPartyPath = isThirdParty(ipath) + ) + for i, decl := range f.Decls { + gen, ok := decl.(*ast.GenDecl) + if ok && gen.Tok == token.IMPORT { + lastImport = i + // Do not add to import "C", to avoid disrupting the + // association with its doc comment, breaking cgo. + if declImports(gen, "C") { + continue + } + + // Match an empty import decl if that's all that is available. + if len(gen.Specs) == 0 && bestMatch == -1 { + impDecl = gen + } + + // Compute longest shared prefix with imports in this group and find best + // matched import spec. + // 1. Always prefer import spec with longest shared prefix. + // 2. While match length is 0, + // - for stdlib package: prefer first import spec. + // - for third party package: prefer first third party import spec. + // We cannot use last import spec as best match for third party package + // because grouped imports are usually placed last by goimports -local + // flag. + // See issue #19190. + seenAnyThirdParty := false + for j, spec := range gen.Specs { + impspec := spec.(*ast.ImportSpec) + p := importPath(impspec) + n := matchLen(p, ipath) + if n > bestMatch || (bestMatch == 0 && !seenAnyThirdParty && isThirdPartyPath) { + bestMatch = n + impDecl = gen + impIndex = j + } + seenAnyThirdParty = seenAnyThirdParty || isThirdParty(p) + } + } + } + + // If no import decl found, add one after the last import. + if impDecl == nil { + impDecl = &ast.GenDecl{ + Tok: token.IMPORT, + } + if lastImport >= 0 { + impDecl.TokPos = f.Decls[lastImport].End() + } else { + // There are no existing imports. + // Our new import, preceded by a blank line, goes after the package declaration + // and after the comment, if any, that starts on the same line as the + // package declaration. + impDecl.TokPos = f.Package + + file := fset.File(f.Package) + pkgLine := file.Line(f.Package) + for _, c := range f.Comments { + if file.Line(c.Pos()) > pkgLine { + break + } + // +2 for a blank line + impDecl.TokPos = c.End() + 2 + } + } + f.Decls = append(f.Decls, nil) + copy(f.Decls[lastImport+2:], f.Decls[lastImport+1:]) + f.Decls[lastImport+1] = impDecl + } + + // Insert new import at insertAt. + insertAt := 0 + if impIndex >= 0 { + // insert after the found import + insertAt = impIndex + 1 + } + impDecl.Specs = append(impDecl.Specs, nil) + copy(impDecl.Specs[insertAt+1:], impDecl.Specs[insertAt:]) + impDecl.Specs[insertAt] = newImport + pos := impDecl.Pos() + if insertAt > 0 { + // If there is a comment after an existing import, preserve the comment + // position by adding the new import after the comment. + if spec, ok := impDecl.Specs[insertAt-1].(*ast.ImportSpec); ok && spec.Comment != nil { + pos = spec.Comment.End() + } else { + // Assign same position as the previous import, + // so that the sorter sees it as being in the same block. + pos = impDecl.Specs[insertAt-1].Pos() + } + } + if newImport.Name != nil { + newImport.Name.NamePos = pos + } + newImport.Path.ValuePos = pos + newImport.EndPos = pos + + // Clean up parens. impDecl contains at least one spec. + if len(impDecl.Specs) == 1 { + // Remove unneeded parens. + impDecl.Lparen = token.NoPos + } else if !impDecl.Lparen.IsValid() { + // impDecl needs parens added. + impDecl.Lparen = impDecl.Specs[0].Pos() + } + + f.Imports = append(f.Imports, newImport) + + if len(f.Decls) <= 1 { + return true + } + + // Merge all the import declarations into the first one. + var first *ast.GenDecl + for i := 0; i < len(f.Decls); i++ { + decl := f.Decls[i] + gen, ok := decl.(*ast.GenDecl) + if !ok || gen.Tok != token.IMPORT || declImports(gen, "C") { + continue + } + if first == nil { + first = gen + continue // Don't touch the first one. + } + // We now know there is more than one package in this import + // declaration. Ensure that it ends up parenthesized. + first.Lparen = first.Pos() + // Move the imports of the other import declaration to the first one. + for _, spec := range gen.Specs { + spec.(*ast.ImportSpec).Path.ValuePos = first.Pos() + first.Specs = append(first.Specs, spec) + } + f.Decls = append(f.Decls[:i], f.Decls[i+1:]...) + i-- + } + + return true +} + +func isThirdParty(importPath string) bool { + // Third party package import path usually contains "." (".com", ".org", ...) + // This logic is taken from golang.org/x/tools/imports package. + return strings.Contains(importPath, ".") +} + +// DeleteImport deletes the import path from the file f, if present. +func DeleteImport(fset *token.FileSet, f *ast.File, path string) (deleted bool) { + return DeleteNamedImport(fset, f, "", path) +} + +// DeleteNamedImport deletes the import with the given name and path from the file f, if present. +func DeleteNamedImport(fset *token.FileSet, f *ast.File, name, path string) (deleted bool) { + var delspecs []*ast.ImportSpec + var delcomments []*ast.CommentGroup + + // Find the import nodes that import path, if any. + for i := 0; i < len(f.Decls); i++ { + decl := f.Decls[i] + gen, ok := decl.(*ast.GenDecl) + if !ok || gen.Tok != token.IMPORT { + continue + } + for j := 0; j < len(gen.Specs); j++ { + spec := gen.Specs[j] + impspec := spec.(*ast.ImportSpec) + if impspec.Name == nil && name != "" { + continue + } + if impspec.Name != nil && impspec.Name.Name != name { + continue + } + if importPath(impspec) != path { + continue + } + + // We found an import spec that imports path. + // Delete it. + delspecs = append(delspecs, impspec) + deleted = true + copy(gen.Specs[j:], gen.Specs[j+1:]) + gen.Specs = gen.Specs[:len(gen.Specs)-1] + + // If this was the last import spec in this decl, + // delete the decl, too. + if len(gen.Specs) == 0 { + copy(f.Decls[i:], f.Decls[i+1:]) + f.Decls = f.Decls[:len(f.Decls)-1] + i-- + break + } else if len(gen.Specs) == 1 { + if impspec.Doc != nil { + delcomments = append(delcomments, impspec.Doc) + } + if impspec.Comment != nil { + delcomments = append(delcomments, impspec.Comment) + } + for _, cg := range f.Comments { + // Found comment on the same line as the import spec. + if cg.End() < impspec.Pos() && fset.Position(cg.End()).Line == fset.Position(impspec.Pos()).Line { + delcomments = append(delcomments, cg) + break + } + } + + spec := gen.Specs[0].(*ast.ImportSpec) + + // Move the documentation right after the import decl. + if spec.Doc != nil { + for fset.Position(gen.TokPos).Line+1 < fset.Position(spec.Doc.Pos()).Line { + fset.File(gen.TokPos).MergeLine(fset.Position(gen.TokPos).Line) + } + } + for _, cg := range f.Comments { + if cg.End() < spec.Pos() && fset.Position(cg.End()).Line == fset.Position(spec.Pos()).Line { + for fset.Position(gen.TokPos).Line+1 < fset.Position(spec.Pos()).Line { + fset.File(gen.TokPos).MergeLine(fset.Position(gen.TokPos).Line) + } + break + } + } + } + if j > 0 { + lastImpspec := gen.Specs[j-1].(*ast.ImportSpec) + lastLine := fset.Position(lastImpspec.Path.ValuePos).Line + line := fset.Position(impspec.Path.ValuePos).Line + + // We deleted an entry but now there may be + // a blank line-sized hole where the import was. + if line-lastLine > 1 { + // There was a blank line immediately preceding the deleted import, + // so there's no need to close the hole. + // Do nothing. + } else if line != fset.File(gen.Rparen).LineCount() { + // There was no blank line. Close the hole. + fset.File(gen.Rparen).MergeLine(line) + } + } + j-- + } + } + + // Delete imports from f.Imports. + for i := 0; i < len(f.Imports); i++ { + imp := f.Imports[i] + for j, del := range delspecs { + if imp == del { + copy(f.Imports[i:], f.Imports[i+1:]) + f.Imports = f.Imports[:len(f.Imports)-1] + copy(delspecs[j:], delspecs[j+1:]) + delspecs = delspecs[:len(delspecs)-1] + i-- + break + } + } + } + + // Delete comments from f.Comments. + for i := 0; i < len(f.Comments); i++ { + cg := f.Comments[i] + for j, del := range delcomments { + if cg == del { + copy(f.Comments[i:], f.Comments[i+1:]) + f.Comments = f.Comments[:len(f.Comments)-1] + copy(delcomments[j:], delcomments[j+1:]) + delcomments = delcomments[:len(delcomments)-1] + i-- + break + } + } + } + + if len(delspecs) > 0 { + panic(fmt.Sprintf("deleted specs from Decls but not Imports: %v", delspecs)) + } + + return +} + +// RewriteImport rewrites any import of path oldPath to path newPath. +func RewriteImport(fset *token.FileSet, f *ast.File, oldPath, newPath string) (rewrote bool) { + for _, imp := range f.Imports { + if importPath(imp) == oldPath { + rewrote = true + // record old End, because the default is to compute + // it using the length of imp.Path.Value. + imp.EndPos = imp.End() + imp.Path.Value = strconv.Quote(newPath) + } + } + return +} + +// UsesImport reports whether a given import is used. +func UsesImport(f *ast.File, path string) (used bool) { + spec := importSpec(f, path) + if spec == nil { + return + } + + name := spec.Name.String() + switch name { + case "": + // If the package name is not explicitly specified, + // make an educated guess. This is not guaranteed to be correct. + lastSlash := strings.LastIndex(path, "/") + if lastSlash == -1 { + name = path + } else { + name = path[lastSlash+1:] + } + case "_", ".": + // Not sure if this import is used - err on the side of caution. + return true + } + + ast.Walk(visitFn(func(n ast.Node) { + sel, ok := n.(*ast.SelectorExpr) + if ok && isTopName(sel.X, name) { + used = true + } + }), f) + + return +} + +type visitFn func(node ast.Node) + +func (fn visitFn) Visit(node ast.Node) ast.Visitor { + fn(node) + return fn +} + +// imports returns true if f imports path. +func imports(f *ast.File, path string) bool { + return importSpec(f, path) != nil +} + +// importSpec returns the import spec if f imports path, +// or nil otherwise. +func importSpec(f *ast.File, path string) *ast.ImportSpec { + for _, s := range f.Imports { + if importPath(s) == path { + return s + } + } + return nil +} + +// importPath returns the unquoted import path of s, +// or "" if the path is not properly quoted. +func importPath(s *ast.ImportSpec) string { + t, err := strconv.Unquote(s.Path.Value) + if err == nil { + return t + } + return "" +} + +// declImports reports whether gen contains an import of path. +func declImports(gen *ast.GenDecl, path string) bool { + if gen.Tok != token.IMPORT { + return false + } + for _, spec := range gen.Specs { + impspec := spec.(*ast.ImportSpec) + if importPath(impspec) == path { + return true + } + } + return false +} + +// matchLen returns the length of the longest path segment prefix shared by x and y. +func matchLen(x, y string) int { + n := 0 + for i := 0; i < len(x) && i < len(y) && x[i] == y[i]; i++ { + if x[i] == '/' { + n++ + } + } + return n +} + +// isTopName returns true if n is a top-level unresolved identifier with the given name. +func isTopName(n ast.Expr, name string) bool { + id, ok := n.(*ast.Ident) + return ok && id.Name == name && id.Obj == nil +} + +// Imports returns the file imports grouped by paragraph. +func Imports(fset *token.FileSet, f *ast.File) [][]*ast.ImportSpec { + var groups [][]*ast.ImportSpec + + for _, decl := range f.Decls { + genDecl, ok := decl.(*ast.GenDecl) + if !ok || genDecl.Tok != token.IMPORT { + break + } + + group := []*ast.ImportSpec{} + + var lastLine int + for _, spec := range genDecl.Specs { + importSpec := spec.(*ast.ImportSpec) + pos := importSpec.Path.ValuePos + line := fset.Position(pos).Line + if lastLine > 0 && pos > 0 && line-lastLine > 1 { + groups = append(groups, group) + group = []*ast.ImportSpec{} + } + group = append(group, importSpec) + lastLine = line + } + groups = append(groups, group) + } + + return groups +} diff --git a/vendor/golang.org/x/tools/go/ast/astutil/rewrite.go b/vendor/golang.org/x/tools/go/ast/astutil/rewrite.go new file mode 100644 index 0000000000..cf72ea990b --- /dev/null +++ b/vendor/golang.org/x/tools/go/ast/astutil/rewrite.go @@ -0,0 +1,477 @@ +// Copyright 2017 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package astutil + +import ( + "fmt" + "go/ast" + "reflect" + "sort" +) + +// An ApplyFunc is invoked by Apply for each node n, even if n is nil, +// before and/or after the node's children, using a Cursor describing +// the current node and providing operations on it. +// +// The return value of ApplyFunc controls the syntax tree traversal. +// See Apply for details. +type ApplyFunc func(*Cursor) bool + +// Apply traverses a syntax tree recursively, starting with root, +// and calling pre and post for each node as described below. +// Apply returns the syntax tree, possibly modified. +// +// If pre is not nil, it is called for each node before the node's +// children are traversed (pre-order). If pre returns false, no +// children are traversed, and post is not called for that node. +// +// If post is not nil, and a prior call of pre didn't return false, +// post is called for each node after its children are traversed +// (post-order). If post returns false, traversal is terminated and +// Apply returns immediately. +// +// Only fields that refer to AST nodes are considered children; +// i.e., token.Pos, Scopes, Objects, and fields of basic types +// (strings, etc.) are ignored. +// +// Children are traversed in the order in which they appear in the +// respective node's struct definition. A package's files are +// traversed in the filenames' alphabetical order. +// +func Apply(root ast.Node, pre, post ApplyFunc) (result ast.Node) { + parent := &struct{ ast.Node }{root} + defer func() { + if r := recover(); r != nil && r != abort { + panic(r) + } + result = parent.Node + }() + a := &application{pre: pre, post: post} + a.apply(parent, "Node", nil, root) + return +} + +var abort = new(int) // singleton, to signal termination of Apply + +// A Cursor describes a node encountered during Apply. +// Information about the node and its parent is available +// from the Node, Parent, Name, and Index methods. +// +// If p is a variable of type and value of the current parent node +// c.Parent(), and f is the field identifier with name c.Name(), +// the following invariants hold: +// +// p.f == c.Node() if c.Index() < 0 +// p.f[c.Index()] == c.Node() if c.Index() >= 0 +// +// The methods Replace, Delete, InsertBefore, and InsertAfter +// can be used to change the AST without disrupting Apply. +type Cursor struct { + parent ast.Node + name string + iter *iterator // valid if non-nil + node ast.Node +} + +// Node returns the current Node. +func (c *Cursor) Node() ast.Node { return c.node } + +// Parent returns the parent of the current Node. +func (c *Cursor) Parent() ast.Node { return c.parent } + +// Name returns the name of the parent Node field that contains the current Node. +// If the parent is a *ast.Package and the current Node is a *ast.File, Name returns +// the filename for the current Node. +func (c *Cursor) Name() string { return c.name } + +// Index reports the index >= 0 of the current Node in the slice of Nodes that +// contains it, or a value < 0 if the current Node is not part of a slice. +// The index of the current node changes if InsertBefore is called while +// processing the current node. +func (c *Cursor) Index() int { + if c.iter != nil { + return c.iter.index + } + return -1 +} + +// field returns the current node's parent field value. +func (c *Cursor) field() reflect.Value { + return reflect.Indirect(reflect.ValueOf(c.parent)).FieldByName(c.name) +} + +// Replace replaces the current Node with n. +// The replacement node is not walked by Apply. +func (c *Cursor) Replace(n ast.Node) { + if _, ok := c.node.(*ast.File); ok { + file, ok := n.(*ast.File) + if !ok { + panic("attempt to replace *ast.File with non-*ast.File") + } + c.parent.(*ast.Package).Files[c.name] = file + return + } + + v := c.field() + if i := c.Index(); i >= 0 { + v = v.Index(i) + } + v.Set(reflect.ValueOf(n)) +} + +// Delete deletes the current Node from its containing slice. +// If the current Node is not part of a slice, Delete panics. +// As a special case, if the current node is a package file, +// Delete removes it from the package's Files map. +func (c *Cursor) Delete() { + if _, ok := c.node.(*ast.File); ok { + delete(c.parent.(*ast.Package).Files, c.name) + return + } + + i := c.Index() + if i < 0 { + panic("Delete node not contained in slice") + } + v := c.field() + l := v.Len() + reflect.Copy(v.Slice(i, l), v.Slice(i+1, l)) + v.Index(l - 1).Set(reflect.Zero(v.Type().Elem())) + v.SetLen(l - 1) + c.iter.step-- +} + +// InsertAfter inserts n after the current Node in its containing slice. +// If the current Node is not part of a slice, InsertAfter panics. +// Apply does not walk n. +func (c *Cursor) InsertAfter(n ast.Node) { + i := c.Index() + if i < 0 { + panic("InsertAfter node not contained in slice") + } + v := c.field() + v.Set(reflect.Append(v, reflect.Zero(v.Type().Elem()))) + l := v.Len() + reflect.Copy(v.Slice(i+2, l), v.Slice(i+1, l)) + v.Index(i + 1).Set(reflect.ValueOf(n)) + c.iter.step++ +} + +// InsertBefore inserts n before the current Node in its containing slice. +// If the current Node is not part of a slice, InsertBefore panics. +// Apply will not walk n. +func (c *Cursor) InsertBefore(n ast.Node) { + i := c.Index() + if i < 0 { + panic("InsertBefore node not contained in slice") + } + v := c.field() + v.Set(reflect.Append(v, reflect.Zero(v.Type().Elem()))) + l := v.Len() + reflect.Copy(v.Slice(i+1, l), v.Slice(i, l)) + v.Index(i).Set(reflect.ValueOf(n)) + c.iter.index++ +} + +// application carries all the shared data so we can pass it around cheaply. +type application struct { + pre, post ApplyFunc + cursor Cursor + iter iterator +} + +func (a *application) apply(parent ast.Node, name string, iter *iterator, n ast.Node) { + // convert typed nil into untyped nil + if v := reflect.ValueOf(n); v.Kind() == reflect.Ptr && v.IsNil() { + n = nil + } + + // avoid heap-allocating a new cursor for each apply call; reuse a.cursor instead + saved := a.cursor + a.cursor.parent = parent + a.cursor.name = name + a.cursor.iter = iter + a.cursor.node = n + + if a.pre != nil && !a.pre(&a.cursor) { + a.cursor = saved + return + } + + // walk children + // (the order of the cases matches the order of the corresponding node types in go/ast) + switch n := n.(type) { + case nil: + // nothing to do + + // Comments and fields + case *ast.Comment: + // nothing to do + + case *ast.CommentGroup: + if n != nil { + a.applyList(n, "List") + } + + case *ast.Field: + a.apply(n, "Doc", nil, n.Doc) + a.applyList(n, "Names") + a.apply(n, "Type", nil, n.Type) + a.apply(n, "Tag", nil, n.Tag) + a.apply(n, "Comment", nil, n.Comment) + + case *ast.FieldList: + a.applyList(n, "List") + + // Expressions + case *ast.BadExpr, *ast.Ident, *ast.BasicLit: + // nothing to do + + case *ast.Ellipsis: + a.apply(n, "Elt", nil, n.Elt) + + case *ast.FuncLit: + a.apply(n, "Type", nil, n.Type) + a.apply(n, "Body", nil, n.Body) + + case *ast.CompositeLit: + a.apply(n, "Type", nil, n.Type) + a.applyList(n, "Elts") + + case *ast.ParenExpr: + a.apply(n, "X", nil, n.X) + + case *ast.SelectorExpr: + a.apply(n, "X", nil, n.X) + a.apply(n, "Sel", nil, n.Sel) + + case *ast.IndexExpr: + a.apply(n, "X", nil, n.X) + a.apply(n, "Index", nil, n.Index) + + case *ast.SliceExpr: + a.apply(n, "X", nil, n.X) + a.apply(n, "Low", nil, n.Low) + a.apply(n, "High", nil, n.High) + a.apply(n, "Max", nil, n.Max) + + case *ast.TypeAssertExpr: + a.apply(n, "X", nil, n.X) + a.apply(n, "Type", nil, n.Type) + + case *ast.CallExpr: + a.apply(n, "Fun", nil, n.Fun) + a.applyList(n, "Args") + + case *ast.StarExpr: + a.apply(n, "X", nil, n.X) + + case *ast.UnaryExpr: + a.apply(n, "X", nil, n.X) + + case *ast.BinaryExpr: + a.apply(n, "X", nil, n.X) + a.apply(n, "Y", nil, n.Y) + + case *ast.KeyValueExpr: + a.apply(n, "Key", nil, n.Key) + a.apply(n, "Value", nil, n.Value) + + // Types + case *ast.ArrayType: + a.apply(n, "Len", nil, n.Len) + a.apply(n, "Elt", nil, n.Elt) + + case *ast.StructType: + a.apply(n, "Fields", nil, n.Fields) + + case *ast.FuncType: + a.apply(n, "Params", nil, n.Params) + a.apply(n, "Results", nil, n.Results) + + case *ast.InterfaceType: + a.apply(n, "Methods", nil, n.Methods) + + case *ast.MapType: + a.apply(n, "Key", nil, n.Key) + a.apply(n, "Value", nil, n.Value) + + case *ast.ChanType: + a.apply(n, "Value", nil, n.Value) + + // Statements + case *ast.BadStmt: + // nothing to do + + case *ast.DeclStmt: + a.apply(n, "Decl", nil, n.Decl) + + case *ast.EmptyStmt: + // nothing to do + + case *ast.LabeledStmt: + a.apply(n, "Label", nil, n.Label) + a.apply(n, "Stmt", nil, n.Stmt) + + case *ast.ExprStmt: + a.apply(n, "X", nil, n.X) + + case *ast.SendStmt: + a.apply(n, "Chan", nil, n.Chan) + a.apply(n, "Value", nil, n.Value) + + case *ast.IncDecStmt: + a.apply(n, "X", nil, n.X) + + case *ast.AssignStmt: + a.applyList(n, "Lhs") + a.applyList(n, "Rhs") + + case *ast.GoStmt: + a.apply(n, "Call", nil, n.Call) + + case *ast.DeferStmt: + a.apply(n, "Call", nil, n.Call) + + case *ast.ReturnStmt: + a.applyList(n, "Results") + + case *ast.BranchStmt: + a.apply(n, "Label", nil, n.Label) + + case *ast.BlockStmt: + a.applyList(n, "List") + + case *ast.IfStmt: + a.apply(n, "Init", nil, n.Init) + a.apply(n, "Cond", nil, n.Cond) + a.apply(n, "Body", nil, n.Body) + a.apply(n, "Else", nil, n.Else) + + case *ast.CaseClause: + a.applyList(n, "List") + a.applyList(n, "Body") + + case *ast.SwitchStmt: + a.apply(n, "Init", nil, n.Init) + a.apply(n, "Tag", nil, n.Tag) + a.apply(n, "Body", nil, n.Body) + + case *ast.TypeSwitchStmt: + a.apply(n, "Init", nil, n.Init) + a.apply(n, "Assign", nil, n.Assign) + a.apply(n, "Body", nil, n.Body) + + case *ast.CommClause: + a.apply(n, "Comm", nil, n.Comm) + a.applyList(n, "Body") + + case *ast.SelectStmt: + a.apply(n, "Body", nil, n.Body) + + case *ast.ForStmt: + a.apply(n, "Init", nil, n.Init) + a.apply(n, "Cond", nil, n.Cond) + a.apply(n, "Post", nil, n.Post) + a.apply(n, "Body", nil, n.Body) + + case *ast.RangeStmt: + a.apply(n, "Key", nil, n.Key) + a.apply(n, "Value", nil, n.Value) + a.apply(n, "X", nil, n.X) + a.apply(n, "Body", nil, n.Body) + + // Declarations + case *ast.ImportSpec: + a.apply(n, "Doc", nil, n.Doc) + a.apply(n, "Name", nil, n.Name) + a.apply(n, "Path", nil, n.Path) + a.apply(n, "Comment", nil, n.Comment) + + case *ast.ValueSpec: + a.apply(n, "Doc", nil, n.Doc) + a.applyList(n, "Names") + a.apply(n, "Type", nil, n.Type) + a.applyList(n, "Values") + a.apply(n, "Comment", nil, n.Comment) + + case *ast.TypeSpec: + a.apply(n, "Doc", nil, n.Doc) + a.apply(n, "Name", nil, n.Name) + a.apply(n, "Type", nil, n.Type) + a.apply(n, "Comment", nil, n.Comment) + + case *ast.BadDecl: + // nothing to do + + case *ast.GenDecl: + a.apply(n, "Doc", nil, n.Doc) + a.applyList(n, "Specs") + + case *ast.FuncDecl: + a.apply(n, "Doc", nil, n.Doc) + a.apply(n, "Recv", nil, n.Recv) + a.apply(n, "Name", nil, n.Name) + a.apply(n, "Type", nil, n.Type) + a.apply(n, "Body", nil, n.Body) + + // Files and packages + case *ast.File: + a.apply(n, "Doc", nil, n.Doc) + a.apply(n, "Name", nil, n.Name) + a.applyList(n, "Decls") + // Don't walk n.Comments; they have either been walked already if + // they are Doc comments, or they can be easily walked explicitly. + + case *ast.Package: + // collect and sort names for reproducible behavior + var names []string + for name := range n.Files { + names = append(names, name) + } + sort.Strings(names) + for _, name := range names { + a.apply(n, name, nil, n.Files[name]) + } + + default: + panic(fmt.Sprintf("Apply: unexpected node type %T", n)) + } + + if a.post != nil && !a.post(&a.cursor) { + panic(abort) + } + + a.cursor = saved +} + +// An iterator controls iteration over a slice of nodes. +type iterator struct { + index, step int +} + +func (a *application) applyList(parent ast.Node, name string) { + // avoid heap-allocating a new iterator for each applyList call; reuse a.iter instead + saved := a.iter + a.iter.index = 0 + for { + // must reload parent.name each time, since cursor modifications might change it + v := reflect.Indirect(reflect.ValueOf(parent)).FieldByName(name) + if a.iter.index >= v.Len() { + break + } + + // element x may be nil in a bad AST - be cautious + var x ast.Node + if e := v.Index(a.iter.index); e.IsValid() { + x = e.Interface().(ast.Node) + } + + a.iter.step = 1 + a.apply(parent, name, &a.iter, x) + a.iter.index += a.iter.step + } + a.iter = saved +} diff --git a/vendor/golang.org/x/tools/go/ast/astutil/util.go b/vendor/golang.org/x/tools/go/ast/astutil/util.go new file mode 100644 index 0000000000..7630629824 --- /dev/null +++ b/vendor/golang.org/x/tools/go/ast/astutil/util.go @@ -0,0 +1,14 @@ +package astutil + +import "go/ast" + +// Unparen returns e with any enclosing parentheses stripped. +func Unparen(e ast.Expr) ast.Expr { + for { + p, ok := e.(*ast.ParenExpr) + if !ok { + return e + } + e = p.X + } +} diff --git a/vendor/golang.org/x/tools/go/buildutil/allpackages.go b/vendor/golang.org/x/tools/go/buildutil/allpackages.go new file mode 100644 index 0000000000..c0cb03e7be --- /dev/null +++ b/vendor/golang.org/x/tools/go/buildutil/allpackages.go @@ -0,0 +1,198 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package buildutil provides utilities related to the go/build +// package in the standard library. +// +// All I/O is done via the build.Context file system interface, which must +// be concurrency-safe. +package buildutil // import "golang.org/x/tools/go/buildutil" + +import ( + "go/build" + "os" + "path/filepath" + "sort" + "strings" + "sync" +) + +// AllPackages returns the package path of each Go package in any source +// directory of the specified build context (e.g. $GOROOT or an element +// of $GOPATH). Errors are ignored. The results are sorted. +// All package paths are canonical, and thus may contain "/vendor/". +// +// The result may include import paths for directories that contain no +// *.go files, such as "archive" (in $GOROOT/src). +// +// All I/O is done via the build.Context file system interface, +// which must be concurrency-safe. +// +func AllPackages(ctxt *build.Context) []string { + var list []string + ForEachPackage(ctxt, func(pkg string, _ error) { + list = append(list, pkg) + }) + sort.Strings(list) + return list +} + +// ForEachPackage calls the found function with the package path of +// each Go package it finds in any source directory of the specified +// build context (e.g. $GOROOT or an element of $GOPATH). +// All package paths are canonical, and thus may contain "/vendor/". +// +// If the package directory exists but could not be read, the second +// argument to the found function provides the error. +// +// All I/O is done via the build.Context file system interface, +// which must be concurrency-safe. +// +func ForEachPackage(ctxt *build.Context, found func(importPath string, err error)) { + ch := make(chan item) + + var wg sync.WaitGroup + for _, root := range ctxt.SrcDirs() { + root := root + wg.Add(1) + go func() { + allPackages(ctxt, root, ch) + wg.Done() + }() + } + go func() { + wg.Wait() + close(ch) + }() + + // All calls to found occur in the caller's goroutine. + for i := range ch { + found(i.importPath, i.err) + } +} + +type item struct { + importPath string + err error // (optional) +} + +// We use a process-wide counting semaphore to limit +// the number of parallel calls to ReadDir. +var ioLimit = make(chan bool, 20) + +func allPackages(ctxt *build.Context, root string, ch chan<- item) { + root = filepath.Clean(root) + string(os.PathSeparator) + + var wg sync.WaitGroup + + var walkDir func(dir string) + walkDir = func(dir string) { + // Avoid .foo, _foo, and testdata directory trees. + base := filepath.Base(dir) + if base == "" || base[0] == '.' || base[0] == '_' || base == "testdata" { + return + } + + pkg := filepath.ToSlash(strings.TrimPrefix(dir, root)) + + // Prune search if we encounter any of these import paths. + switch pkg { + case "builtin": + return + } + + ioLimit <- true + files, err := ReadDir(ctxt, dir) + <-ioLimit + if pkg != "" || err != nil { + ch <- item{pkg, err} + } + for _, fi := range files { + fi := fi + if fi.IsDir() { + wg.Add(1) + go func() { + walkDir(filepath.Join(dir, fi.Name())) + wg.Done() + }() + } + } + } + + walkDir(root) + wg.Wait() +} + +// ExpandPatterns returns the set of packages matched by patterns, +// which may have the following forms: +// +// golang.org/x/tools/cmd/guru # a single package +// golang.org/x/tools/... # all packages beneath dir +// ... # the entire workspace. +// +// Order is significant: a pattern preceded by '-' removes matching +// packages from the set. For example, these patterns match all encoding +// packages except encoding/xml: +// +// encoding/... -encoding/xml +// +// A trailing slash in a pattern is ignored. (Path components of Go +// package names are separated by slash, not the platform's path separator.) +// +func ExpandPatterns(ctxt *build.Context, patterns []string) map[string]bool { + // TODO(adonovan): support other features of 'go list': + // - "std"/"cmd"/"all" meta-packages + // - "..." not at the end of a pattern + // - relative patterns using "./" or "../" prefix + + pkgs := make(map[string]bool) + doPkg := func(pkg string, neg bool) { + if neg { + delete(pkgs, pkg) + } else { + pkgs[pkg] = true + } + } + + // Scan entire workspace if wildcards are present. + // TODO(adonovan): opt: scan only the necessary subtrees of the workspace. + var all []string + for _, arg := range patterns { + if strings.HasSuffix(arg, "...") { + all = AllPackages(ctxt) + break + } + } + + for _, arg := range patterns { + if arg == "" { + continue + } + + neg := arg[0] == '-' + if neg { + arg = arg[1:] + } + + if arg == "..." { + // ... matches all packages + for _, pkg := range all { + doPkg(pkg, neg) + } + } else if dir := strings.TrimSuffix(arg, "/..."); dir != arg { + // dir/... matches all packages beneath dir + for _, pkg := range all { + if strings.HasPrefix(pkg, dir) && + (len(pkg) == len(dir) || pkg[len(dir)] == '/') { + doPkg(pkg, neg) + } + } + } else { + // single package + doPkg(strings.TrimSuffix(arg, "/"), neg) + } + } + + return pkgs +} diff --git a/vendor/golang.org/x/tools/go/buildutil/fakecontext.go b/vendor/golang.org/x/tools/go/buildutil/fakecontext.go new file mode 100644 index 0000000000..8b7f066739 --- /dev/null +++ b/vendor/golang.org/x/tools/go/buildutil/fakecontext.go @@ -0,0 +1,109 @@ +package buildutil + +import ( + "fmt" + "go/build" + "io" + "io/ioutil" + "os" + "path" + "path/filepath" + "sort" + "strings" + "time" +) + +// FakeContext returns a build.Context for the fake file tree specified +// by pkgs, which maps package import paths to a mapping from file base +// names to contents. +// +// The fake Context has a GOROOT of "/go" and no GOPATH, and overrides +// the necessary file access methods to read from memory instead of the +// real file system. +// +// Unlike a real file tree, the fake one has only two levels---packages +// and files---so ReadDir("/go/src/") returns all packages under +// /go/src/ including, for instance, "math" and "math/big". +// ReadDir("/go/src/math/big") would return all the files in the +// "math/big" package. +// +func FakeContext(pkgs map[string]map[string]string) *build.Context { + clean := func(filename string) string { + f := path.Clean(filepath.ToSlash(filename)) + // Removing "/go/src" while respecting segment + // boundaries has this unfortunate corner case: + if f == "/go/src" { + return "" + } + return strings.TrimPrefix(f, "/go/src/") + } + + ctxt := build.Default // copy + ctxt.GOROOT = "/go" + ctxt.GOPATH = "" + ctxt.Compiler = "gc" + ctxt.IsDir = func(dir string) bool { + dir = clean(dir) + if dir == "" { + return true // needed by (*build.Context).SrcDirs + } + return pkgs[dir] != nil + } + ctxt.ReadDir = func(dir string) ([]os.FileInfo, error) { + dir = clean(dir) + var fis []os.FileInfo + if dir == "" { + // enumerate packages + for importPath := range pkgs { + fis = append(fis, fakeDirInfo(importPath)) + } + } else { + // enumerate files of package + for basename := range pkgs[dir] { + fis = append(fis, fakeFileInfo(basename)) + } + } + sort.Sort(byName(fis)) + return fis, nil + } + ctxt.OpenFile = func(filename string) (io.ReadCloser, error) { + filename = clean(filename) + dir, base := path.Split(filename) + content, ok := pkgs[path.Clean(dir)][base] + if !ok { + return nil, fmt.Errorf("file not found: %s", filename) + } + return ioutil.NopCloser(strings.NewReader(content)), nil + } + ctxt.IsAbsPath = func(path string) bool { + path = filepath.ToSlash(path) + // Don't rely on the default (filepath.Path) since on + // Windows, it reports virtual paths as non-absolute. + return strings.HasPrefix(path, "/") + } + return &ctxt +} + +type byName []os.FileInfo + +func (s byName) Len() int { return len(s) } +func (s byName) Swap(i, j int) { s[i], s[j] = s[j], s[i] } +func (s byName) Less(i, j int) bool { return s[i].Name() < s[j].Name() } + +type fakeFileInfo string + +func (fi fakeFileInfo) Name() string { return string(fi) } +func (fakeFileInfo) Sys() interface{} { return nil } +func (fakeFileInfo) ModTime() time.Time { return time.Time{} } +func (fakeFileInfo) IsDir() bool { return false } +func (fakeFileInfo) Size() int64 { return 0 } +func (fakeFileInfo) Mode() os.FileMode { return 0644 } + +type fakeDirInfo string + +func (fd fakeDirInfo) Name() string { return string(fd) } +func (fakeDirInfo) Sys() interface{} { return nil } +func (fakeDirInfo) ModTime() time.Time { return time.Time{} } +func (fakeDirInfo) IsDir() bool { return true } +func (fakeDirInfo) Size() int64 { return 0 } +func (fakeDirInfo) Mode() os.FileMode { return 0755 } diff --git a/vendor/golang.org/x/tools/go/buildutil/overlay.go b/vendor/golang.org/x/tools/go/buildutil/overlay.go new file mode 100644 index 0000000000..3f71c4fef7 --- /dev/null +++ b/vendor/golang.org/x/tools/go/buildutil/overlay.go @@ -0,0 +1,103 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package buildutil + +import ( + "bufio" + "bytes" + "fmt" + "go/build" + "io" + "io/ioutil" + "path/filepath" + "strconv" + "strings" +) + +// OverlayContext overlays a build.Context with additional files from +// a map. Files in the map take precedence over other files. +// +// In addition to plain string comparison, two file names are +// considered equal if their base names match and their directory +// components point at the same directory on the file system. That is, +// symbolic links are followed for directories, but not files. +// +// A common use case for OverlayContext is to allow editors to pass in +// a set of unsaved, modified files. +// +// Currently, only the Context.OpenFile function will respect the +// overlay. This may change in the future. +func OverlayContext(orig *build.Context, overlay map[string][]byte) *build.Context { + // TODO(dominikh): Implement IsDir, HasSubdir and ReadDir + + rc := func(data []byte) (io.ReadCloser, error) { + return ioutil.NopCloser(bytes.NewBuffer(data)), nil + } + + copy := *orig // make a copy + ctxt := © + ctxt.OpenFile = func(path string) (io.ReadCloser, error) { + // Fast path: names match exactly. + if content, ok := overlay[path]; ok { + return rc(content) + } + + // Slow path: check for same file under a different + // alias, perhaps due to a symbolic link. + for filename, content := range overlay { + if sameFile(path, filename) { + return rc(content) + } + } + + return OpenFile(orig, path) + } + return ctxt +} + +// ParseOverlayArchive parses an archive containing Go files and their +// contents. The result is intended to be used with OverlayContext. +// +// +// Archive format +// +// The archive consists of a series of files. Each file consists of a +// name, a decimal file size and the file contents, separated by +// newlinews. No newline follows after the file contents. +func ParseOverlayArchive(archive io.Reader) (map[string][]byte, error) { + overlay := make(map[string][]byte) + r := bufio.NewReader(archive) + for { + // Read file name. + filename, err := r.ReadString('\n') + if err != nil { + if err == io.EOF { + break // OK + } + return nil, fmt.Errorf("reading archive file name: %v", err) + } + filename = filepath.Clean(strings.TrimSpace(filename)) + + // Read file size. + sz, err := r.ReadString('\n') + if err != nil { + return nil, fmt.Errorf("reading size of archive file %s: %v", filename, err) + } + sz = strings.TrimSpace(sz) + size, err := strconv.ParseUint(sz, 10, 32) + if err != nil { + return nil, fmt.Errorf("parsing size of archive file %s: %v", filename, err) + } + + // Read file content. + content := make([]byte, size) + if _, err := io.ReadFull(r, content); err != nil { + return nil, fmt.Errorf("reading archive file %s: %v", filename, err) + } + overlay[filename] = content + } + + return overlay, nil +} diff --git a/vendor/golang.org/x/tools/go/buildutil/tags.go b/vendor/golang.org/x/tools/go/buildutil/tags.go new file mode 100644 index 0000000000..486606f376 --- /dev/null +++ b/vendor/golang.org/x/tools/go/buildutil/tags.go @@ -0,0 +1,75 @@ +package buildutil + +// This logic was copied from stringsFlag from $GOROOT/src/cmd/go/build.go. + +import "fmt" + +const TagsFlagDoc = "a list of `build tags` to consider satisfied during the build. " + + "For more information about build tags, see the description of " + + "build constraints in the documentation for the go/build package" + +// TagsFlag is an implementation of the flag.Value and flag.Getter interfaces that parses +// a flag value in the same manner as go build's -tags flag and +// populates a []string slice. +// +// See $GOROOT/src/go/build/doc.go for description of build tags. +// See $GOROOT/src/cmd/go/doc.go for description of 'go build -tags' flag. +// +// Example: +// flag.Var((*buildutil.TagsFlag)(&build.Default.BuildTags), "tags", buildutil.TagsFlagDoc) +type TagsFlag []string + +func (v *TagsFlag) Set(s string) error { + var err error + *v, err = splitQuotedFields(s) + if *v == nil { + *v = []string{} + } + return err +} + +func (v *TagsFlag) Get() interface{} { return *v } + +func splitQuotedFields(s string) ([]string, error) { + // Split fields allowing '' or "" around elements. + // Quotes further inside the string do not count. + var f []string + for len(s) > 0 { + for len(s) > 0 && isSpaceByte(s[0]) { + s = s[1:] + } + if len(s) == 0 { + break + } + // Accepted quoted string. No unescaping inside. + if s[0] == '"' || s[0] == '\'' { + quote := s[0] + s = s[1:] + i := 0 + for i < len(s) && s[i] != quote { + i++ + } + if i >= len(s) { + return nil, fmt.Errorf("unterminated %c string", quote) + } + f = append(f, s[:i]) + s = s[i+1:] + continue + } + i := 0 + for i < len(s) && !isSpaceByte(s[i]) { + i++ + } + f = append(f, s[:i]) + s = s[i:] + } + return f, nil +} + +func (v *TagsFlag) String() string { + return "" +} + +func isSpaceByte(c byte) bool { + return c == ' ' || c == '\t' || c == '\n' || c == '\r' +} diff --git a/vendor/golang.org/x/tools/go/buildutil/util.go b/vendor/golang.org/x/tools/go/buildutil/util.go new file mode 100644 index 0000000000..fc923d7a70 --- /dev/null +++ b/vendor/golang.org/x/tools/go/buildutil/util.go @@ -0,0 +1,212 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package buildutil + +import ( + "fmt" + "go/ast" + "go/build" + "go/parser" + "go/token" + "io" + "io/ioutil" + "os" + "path" + "path/filepath" + "strings" +) + +// ParseFile behaves like parser.ParseFile, +// but uses the build context's file system interface, if any. +// +// If file is not absolute (as defined by IsAbsPath), the (dir, file) +// components are joined using JoinPath; dir must be absolute. +// +// The displayPath function, if provided, is used to transform the +// filename that will be attached to the ASTs. +// +// TODO(adonovan): call this from go/loader.parseFiles when the tree thaws. +// +func ParseFile(fset *token.FileSet, ctxt *build.Context, displayPath func(string) string, dir string, file string, mode parser.Mode) (*ast.File, error) { + if !IsAbsPath(ctxt, file) { + file = JoinPath(ctxt, dir, file) + } + rd, err := OpenFile(ctxt, file) + if err != nil { + return nil, err + } + defer rd.Close() // ignore error + if displayPath != nil { + file = displayPath(file) + } + return parser.ParseFile(fset, file, rd, mode) +} + +// ContainingPackage returns the package containing filename. +// +// If filename is not absolute, it is interpreted relative to working directory dir. +// All I/O is via the build context's file system interface, if any. +// +// The '...Files []string' fields of the resulting build.Package are not +// populated (build.FindOnly mode). +// +func ContainingPackage(ctxt *build.Context, dir, filename string) (*build.Package, error) { + if !IsAbsPath(ctxt, filename) { + filename = JoinPath(ctxt, dir, filename) + } + + // We must not assume the file tree uses + // "/" always, + // `\` always, + // or os.PathSeparator (which varies by platform), + // but to make any progress, we are forced to assume that + // paths will not use `\` unless the PathSeparator + // is also `\`, thus we can rely on filepath.ToSlash for some sanity. + + dirSlash := path.Dir(filepath.ToSlash(filename)) + "/" + + // We assume that no source root (GOPATH[i] or GOROOT) contains any other. + for _, srcdir := range ctxt.SrcDirs() { + srcdirSlash := filepath.ToSlash(srcdir) + "/" + if importPath, ok := HasSubdir(ctxt, srcdirSlash, dirSlash); ok { + return ctxt.Import(importPath, dir, build.FindOnly) + } + } + + return nil, fmt.Errorf("can't find package containing %s", filename) +} + +// -- Effective methods of file system interface ------------------------- + +// (go/build.Context defines these as methods, but does not export them.) + +// hasSubdir calls ctxt.HasSubdir (if not nil) or else uses +// the local file system to answer the question. +func HasSubdir(ctxt *build.Context, root, dir string) (rel string, ok bool) { + if f := ctxt.HasSubdir; f != nil { + return f(root, dir) + } + + // Try using paths we received. + if rel, ok = hasSubdir(root, dir); ok { + return + } + + // Try expanding symlinks and comparing + // expanded against unexpanded and + // expanded against expanded. + rootSym, _ := filepath.EvalSymlinks(root) + dirSym, _ := filepath.EvalSymlinks(dir) + + if rel, ok = hasSubdir(rootSym, dir); ok { + return + } + if rel, ok = hasSubdir(root, dirSym); ok { + return + } + return hasSubdir(rootSym, dirSym) +} + +func hasSubdir(root, dir string) (rel string, ok bool) { + const sep = string(filepath.Separator) + root = filepath.Clean(root) + if !strings.HasSuffix(root, sep) { + root += sep + } + + dir = filepath.Clean(dir) + if !strings.HasPrefix(dir, root) { + return "", false + } + + return filepath.ToSlash(dir[len(root):]), true +} + +// FileExists returns true if the specified file exists, +// using the build context's file system interface. +func FileExists(ctxt *build.Context, path string) bool { + if ctxt.OpenFile != nil { + r, err := ctxt.OpenFile(path) + if err != nil { + return false + } + r.Close() // ignore error + return true + } + _, err := os.Stat(path) + return err == nil +} + +// OpenFile behaves like os.Open, +// but uses the build context's file system interface, if any. +func OpenFile(ctxt *build.Context, path string) (io.ReadCloser, error) { + if ctxt.OpenFile != nil { + return ctxt.OpenFile(path) + } + return os.Open(path) +} + +// IsAbsPath behaves like filepath.IsAbs, +// but uses the build context's file system interface, if any. +func IsAbsPath(ctxt *build.Context, path string) bool { + if ctxt.IsAbsPath != nil { + return ctxt.IsAbsPath(path) + } + return filepath.IsAbs(path) +} + +// JoinPath behaves like filepath.Join, +// but uses the build context's file system interface, if any. +func JoinPath(ctxt *build.Context, path ...string) string { + if ctxt.JoinPath != nil { + return ctxt.JoinPath(path...) + } + return filepath.Join(path...) +} + +// IsDir behaves like os.Stat plus IsDir, +// but uses the build context's file system interface, if any. +func IsDir(ctxt *build.Context, path string) bool { + if ctxt.IsDir != nil { + return ctxt.IsDir(path) + } + fi, err := os.Stat(path) + return err == nil && fi.IsDir() +} + +// ReadDir behaves like ioutil.ReadDir, +// but uses the build context's file system interface, if any. +func ReadDir(ctxt *build.Context, path string) ([]os.FileInfo, error) { + if ctxt.ReadDir != nil { + return ctxt.ReadDir(path) + } + return ioutil.ReadDir(path) +} + +// SplitPathList behaves like filepath.SplitList, +// but uses the build context's file system interface, if any. +func SplitPathList(ctxt *build.Context, s string) []string { + if ctxt.SplitPathList != nil { + return ctxt.SplitPathList(s) + } + return filepath.SplitList(s) +} + +// sameFile returns true if x and y have the same basename and denote +// the same file. +// +func sameFile(x, y string) bool { + if path.Clean(x) == path.Clean(y) { + return true + } + if filepath.Base(x) == filepath.Base(y) { // (optimisation) + if xi, err := os.Stat(x); err == nil { + if yi, err := os.Stat(y); err == nil { + return os.SameFile(xi, yi) + } + } + } + return false +} diff --git a/vendor/golang.org/x/tools/go/gcexportdata/gcexportdata.go b/vendor/golang.org/x/tools/go/gcexportdata/gcexportdata.go new file mode 100644 index 0000000000..4c238d1013 --- /dev/null +++ b/vendor/golang.org/x/tools/go/gcexportdata/gcexportdata.go @@ -0,0 +1,109 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package gcexportdata provides functions for locating, reading, and +// writing export data files containing type information produced by the +// gc compiler. This package supports go1.7 export data format and all +// later versions. +// +// Although it might seem convenient for this package to live alongside +// go/types in the standard library, this would cause version skew +// problems for developer tools that use it, since they must be able to +// consume the outputs of the gc compiler both before and after a Go +// update such as from Go 1.7 to Go 1.8. Because this package lives in +// golang.org/x/tools, sites can update their version of this repo some +// time before the Go 1.8 release and rebuild and redeploy their +// developer tools, which will then be able to consume both Go 1.7 and +// Go 1.8 export data files, so they will work before and after the +// Go update. (See discussion at https://github.com/golang/go/issues/15651.) +// +package gcexportdata // import "golang.org/x/tools/go/gcexportdata" + +import ( + "bufio" + "bytes" + "fmt" + "go/token" + "go/types" + "io" + "io/ioutil" + + "golang.org/x/tools/go/internal/gcimporter" +) + +// Find returns the name of an object (.o) or archive (.a) file +// containing type information for the specified import path, +// using the workspace layout conventions of go/build. +// If no file was found, an empty filename is returned. +// +// A relative srcDir is interpreted relative to the current working directory. +// +// Find also returns the package's resolved (canonical) import path, +// reflecting the effects of srcDir and vendoring on importPath. +func Find(importPath, srcDir string) (filename, path string) { + return gcimporter.FindPkg(importPath, srcDir) +} + +// NewReader returns a reader for the export data section of an object +// (.o) or archive (.a) file read from r. The new reader may provide +// additional trailing data beyond the end of the export data. +func NewReader(r io.Reader) (io.Reader, error) { + buf := bufio.NewReader(r) + _, err := gcimporter.FindExportData(buf) + // If we ever switch to a zip-like archive format with the ToC + // at the end, we can return the correct portion of export data, + // but for now we must return the entire rest of the file. + return buf, err +} + +// Read reads export data from in, decodes it, and returns type +// information for the package. +// The package name is specified by path. +// File position information is added to fset. +// +// Read may inspect and add to the imports map to ensure that references +// within the export data to other packages are consistent. The caller +// must ensure that imports[path] does not exist, or exists but is +// incomplete (see types.Package.Complete), and Read inserts the +// resulting package into this map entry. +// +// On return, the state of the reader is undefined. +func Read(in io.Reader, fset *token.FileSet, imports map[string]*types.Package, path string) (*types.Package, error) { + data, err := ioutil.ReadAll(in) + if err != nil { + return nil, fmt.Errorf("reading export data for %q: %v", path, err) + } + + if bytes.HasPrefix(data, []byte("!")) { + return nil, fmt.Errorf("can't read export data for %q directly from an archive file (call gcexportdata.NewReader first to extract export data)", path) + } + + // The App Engine Go runtime v1.6 uses the old export data format. + // TODO(adonovan): delete once v1.7 has been around for a while. + if bytes.HasPrefix(data, []byte("package ")) { + return gcimporter.ImportData(imports, path, path, bytes.NewReader(data)) + } + + // The indexed export format starts with an 'i'; the older + // binary export format starts with a 'c', 'd', or 'v' + // (from "version"). Select appropriate importer. + if len(data) > 0 && data[0] == 'i' { + _, pkg, err := gcimporter.IImportData(fset, imports, data[1:], path) + return pkg, err + } + + _, pkg, err := gcimporter.BImportData(fset, imports, data, path) + return pkg, err +} + +// Write writes encoded type information for the specified package to out. +// The FileSet provides file position information for named objects. +func Write(out io.Writer, fset *token.FileSet, pkg *types.Package) error { + b, err := gcimporter.BExportData(fset, pkg) + if err != nil { + return err + } + _, err = out.Write(b) + return err +} diff --git a/vendor/golang.org/x/tools/go/gcexportdata/importer.go b/vendor/golang.org/x/tools/go/gcexportdata/importer.go new file mode 100644 index 0000000000..efe221e7e1 --- /dev/null +++ b/vendor/golang.org/x/tools/go/gcexportdata/importer.go @@ -0,0 +1,73 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package gcexportdata + +import ( + "fmt" + "go/token" + "go/types" + "os" +) + +// NewImporter returns a new instance of the types.Importer interface +// that reads type information from export data files written by gc. +// The Importer also satisfies types.ImporterFrom. +// +// Export data files are located using "go build" workspace conventions +// and the build.Default context. +// +// Use this importer instead of go/importer.For("gc", ...) to avoid the +// version-skew problems described in the documentation of this package, +// or to control the FileSet or access the imports map populated during +// package loading. +// +func NewImporter(fset *token.FileSet, imports map[string]*types.Package) types.ImporterFrom { + return importer{fset, imports} +} + +type importer struct { + fset *token.FileSet + imports map[string]*types.Package +} + +func (imp importer) Import(importPath string) (*types.Package, error) { + return imp.ImportFrom(importPath, "", 0) +} + +func (imp importer) ImportFrom(importPath, srcDir string, mode types.ImportMode) (_ *types.Package, err error) { + filename, path := Find(importPath, srcDir) + if filename == "" { + if importPath == "unsafe" { + // Even for unsafe, call Find first in case + // the package was vendored. + return types.Unsafe, nil + } + return nil, fmt.Errorf("can't find import: %s", importPath) + } + + if pkg, ok := imp.imports[path]; ok && pkg.Complete() { + return pkg, nil // cache hit + } + + // open file + f, err := os.Open(filename) + if err != nil { + return nil, err + } + defer func() { + f.Close() + if err != nil { + // add file name to error + err = fmt.Errorf("reading export data: %s: %v", filename, err) + } + }() + + r, err := NewReader(f) + if err != nil { + return nil, err + } + + return Read(r, imp.fset, imp.imports, path) +} diff --git a/vendor/golang.org/x/tools/go/gcexportdata/main.go b/vendor/golang.org/x/tools/go/gcexportdata/main.go new file mode 100644 index 0000000000..2713dce64a --- /dev/null +++ b/vendor/golang.org/x/tools/go/gcexportdata/main.go @@ -0,0 +1,99 @@ +// Copyright 2017 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build ignore + +// The gcexportdata command is a diagnostic tool that displays the +// contents of gc export data files. +package main + +import ( + "flag" + "fmt" + "go/token" + "go/types" + "log" + "os" + + "golang.org/x/tools/go/gcexportdata" + "golang.org/x/tools/go/types/typeutil" +) + +var packageFlag = flag.String("package", "", "alternative package to print") + +func main() { + log.SetPrefix("gcexportdata: ") + log.SetFlags(0) + flag.Usage = func() { + fmt.Fprintln(os.Stderr, "usage: gcexportdata [-package path] file.a") + } + flag.Parse() + if flag.NArg() != 1 { + flag.Usage() + os.Exit(2) + } + filename := flag.Args()[0] + + f, err := os.Open(filename) + if err != nil { + log.Fatal(err) + } + + r, err := gcexportdata.NewReader(f) + if err != nil { + log.Fatalf("%s: %s", filename, err) + } + + // Decode the package. + const primary = "" + imports := make(map[string]*types.Package) + fset := token.NewFileSet() + pkg, err := gcexportdata.Read(r, fset, imports, primary) + if err != nil { + log.Fatalf("%s: %s", filename, err) + } + + // Optionally select an indirectly mentioned package. + if *packageFlag != "" { + pkg = imports[*packageFlag] + if pkg == nil { + fmt.Fprintf(os.Stderr, "export data file %s does not mention %s; has:\n", + filename, *packageFlag) + for p := range imports { + if p != primary { + fmt.Fprintf(os.Stderr, "\t%s\n", p) + } + } + os.Exit(1) + } + } + + // Print all package-level declarations, including non-exported ones. + fmt.Printf("package %s\n", pkg.Name()) + for _, imp := range pkg.Imports() { + fmt.Printf("import %q\n", imp.Path()) + } + qual := func(p *types.Package) string { + if pkg == p { + return "" + } + return p.Name() + } + scope := pkg.Scope() + for _, name := range scope.Names() { + obj := scope.Lookup(name) + fmt.Printf("%s: %s\n", + fset.Position(obj.Pos()), + types.ObjectString(obj, qual)) + + // For types, print each method. + if _, ok := obj.(*types.TypeName); ok { + for _, method := range typeutil.IntuitiveMethodSet(obj.Type(), nil) { + fmt.Printf("%s: %s\n", + fset.Position(method.Obj().Pos()), + types.SelectionString(method, qual)) + } + } + } +} diff --git a/vendor/golang.org/x/tools/go/internal/cgo/cgo.go b/vendor/golang.org/x/tools/go/internal/cgo/cgo.go new file mode 100644 index 0000000000..0f652ea6fb --- /dev/null +++ b/vendor/golang.org/x/tools/go/internal/cgo/cgo.go @@ -0,0 +1,220 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package cgo + +// This file handles cgo preprocessing of files containing `import "C"`. +// +// DESIGN +// +// The approach taken is to run the cgo processor on the package's +// CgoFiles and parse the output, faking the filenames of the +// resulting ASTs so that the synthetic file containing the C types is +// called "C" (e.g. "~/go/src/net/C") and the preprocessed files +// have their original names (e.g. "~/go/src/net/cgo_unix.go"), +// not the names of the actual temporary files. +// +// The advantage of this approach is its fidelity to 'go build'. The +// downside is that the token.Position.Offset for each AST node is +// incorrect, being an offset within the temporary file. Line numbers +// should still be correct because of the //line comments. +// +// The logic of this file is mostly plundered from the 'go build' +// tool, which also invokes the cgo preprocessor. +// +// +// REJECTED ALTERNATIVE +// +// An alternative approach that we explored is to extend go/types' +// Importer mechanism to provide the identity of the importing package +// so that each time `import "C"` appears it resolves to a different +// synthetic package containing just the objects needed in that case. +// The loader would invoke cgo but parse only the cgo_types.go file +// defining the package-level objects, discarding the other files +// resulting from preprocessing. +// +// The benefit of this approach would have been that source-level +// syntax information would correspond exactly to the original cgo +// file, with no preprocessing involved, making source tools like +// godoc, guru, and eg happy. However, the approach was rejected +// due to the additional complexity it would impose on go/types. (It +// made for a beautiful demo, though.) +// +// cgo files, despite their *.go extension, are not legal Go source +// files per the specification since they may refer to unexported +// members of package "C" such as C.int. Also, a function such as +// C.getpwent has in effect two types, one matching its C type and one +// which additionally returns (errno C.int). The cgo preprocessor +// uses name mangling to distinguish these two functions in the +// processed code, but go/types would need to duplicate this logic in +// its handling of function calls, analogous to the treatment of map +// lookups in which y=m[k] and y,ok=m[k] are both legal. + +import ( + "fmt" + "go/ast" + "go/build" + "go/parser" + "go/token" + "io/ioutil" + "log" + "os" + "os/exec" + "path/filepath" + "regexp" + "strings" +) + +// ProcessFiles invokes the cgo preprocessor on bp.CgoFiles, parses +// the output and returns the resulting ASTs. +// +func ProcessFiles(bp *build.Package, fset *token.FileSet, DisplayPath func(path string) string, mode parser.Mode) ([]*ast.File, error) { + tmpdir, err := ioutil.TempDir("", strings.Replace(bp.ImportPath, "/", "_", -1)+"_C") + if err != nil { + return nil, err + } + defer os.RemoveAll(tmpdir) + + pkgdir := bp.Dir + if DisplayPath != nil { + pkgdir = DisplayPath(pkgdir) + } + + cgoFiles, cgoDisplayFiles, err := Run(bp, pkgdir, tmpdir, false) + if err != nil { + return nil, err + } + var files []*ast.File + for i := range cgoFiles { + rd, err := os.Open(cgoFiles[i]) + if err != nil { + return nil, err + } + display := filepath.Join(bp.Dir, cgoDisplayFiles[i]) + f, err := parser.ParseFile(fset, display, rd, mode) + rd.Close() + if err != nil { + return nil, err + } + files = append(files, f) + } + return files, nil +} + +var cgoRe = regexp.MustCompile(`[/\\:]`) + +// Run invokes the cgo preprocessor on bp.CgoFiles and returns two +// lists of files: the resulting processed files (in temporary +// directory tmpdir) and the corresponding names of the unprocessed files. +// +// Run is adapted from (*builder).cgo in +// $GOROOT/src/cmd/go/build.go, but these features are unsupported: +// Objective C, CGOPKGPATH, CGO_FLAGS. +// +// If useabs is set to true, absolute paths of the bp.CgoFiles will be passed in +// to the cgo preprocessor. This in turn will set the // line comments +// referring to those files to use absolute paths. This is needed for +// go/packages using the legacy go list support so it is able to find +// the original files. +func Run(bp *build.Package, pkgdir, tmpdir string, useabs bool) (files, displayFiles []string, err error) { + cgoCPPFLAGS, _, _, _ := cflags(bp, true) + _, cgoexeCFLAGS, _, _ := cflags(bp, false) + + if len(bp.CgoPkgConfig) > 0 { + pcCFLAGS, err := pkgConfigFlags(bp) + if err != nil { + return nil, nil, err + } + cgoCPPFLAGS = append(cgoCPPFLAGS, pcCFLAGS...) + } + + // Allows including _cgo_export.h from .[ch] files in the package. + cgoCPPFLAGS = append(cgoCPPFLAGS, "-I", tmpdir) + + // _cgo_gotypes.go (displayed "C") contains the type definitions. + files = append(files, filepath.Join(tmpdir, "_cgo_gotypes.go")) + displayFiles = append(displayFiles, "C") + for _, fn := range bp.CgoFiles { + // "foo.cgo1.go" (displayed "foo.go") is the processed Go source. + f := cgoRe.ReplaceAllString(fn[:len(fn)-len("go")], "_") + files = append(files, filepath.Join(tmpdir, f+"cgo1.go")) + displayFiles = append(displayFiles, fn) + } + + var cgoflags []string + if bp.Goroot && bp.ImportPath == "runtime/cgo" { + cgoflags = append(cgoflags, "-import_runtime_cgo=false") + } + if bp.Goroot && bp.ImportPath == "runtime/race" || bp.ImportPath == "runtime/cgo" { + cgoflags = append(cgoflags, "-import_syscall=false") + } + + var cgoFiles []string = bp.CgoFiles + if useabs { + cgoFiles = make([]string, len(bp.CgoFiles)) + for i := range cgoFiles { + cgoFiles[i] = filepath.Join(pkgdir, bp.CgoFiles[i]) + } + } + + args := stringList( + "go", "tool", "cgo", "-objdir", tmpdir, cgoflags, "--", + cgoCPPFLAGS, cgoexeCFLAGS, cgoFiles, + ) + if false { + log.Printf("Running cgo for package %q: %s (dir=%s)", bp.ImportPath, args, pkgdir) + } + cmd := exec.Command(args[0], args[1:]...) + cmd.Dir = pkgdir + cmd.Stdout = os.Stderr + cmd.Stderr = os.Stderr + if err := cmd.Run(); err != nil { + return nil, nil, fmt.Errorf("cgo failed: %s: %s", args, err) + } + + return files, displayFiles, nil +} + +// -- unmodified from 'go build' --------------------------------------- + +// Return the flags to use when invoking the C or C++ compilers, or cgo. +func cflags(p *build.Package, def bool) (cppflags, cflags, cxxflags, ldflags []string) { + var defaults string + if def { + defaults = "-g -O2" + } + + cppflags = stringList(envList("CGO_CPPFLAGS", ""), p.CgoCPPFLAGS) + cflags = stringList(envList("CGO_CFLAGS", defaults), p.CgoCFLAGS) + cxxflags = stringList(envList("CGO_CXXFLAGS", defaults), p.CgoCXXFLAGS) + ldflags = stringList(envList("CGO_LDFLAGS", defaults), p.CgoLDFLAGS) + return +} + +// envList returns the value of the given environment variable broken +// into fields, using the default value when the variable is empty. +func envList(key, def string) []string { + v := os.Getenv(key) + if v == "" { + v = def + } + return strings.Fields(v) +} + +// stringList's arguments should be a sequence of string or []string values. +// stringList flattens them into a single []string. +func stringList(args ...interface{}) []string { + var x []string + for _, arg := range args { + switch arg := arg.(type) { + case []string: + x = append(x, arg...) + case string: + x = append(x, arg) + default: + panic("stringList: invalid argument") + } + } + return x +} diff --git a/vendor/golang.org/x/tools/go/internal/cgo/cgo_pkgconfig.go b/vendor/golang.org/x/tools/go/internal/cgo/cgo_pkgconfig.go new file mode 100644 index 0000000000..b5bb95a63e --- /dev/null +++ b/vendor/golang.org/x/tools/go/internal/cgo/cgo_pkgconfig.go @@ -0,0 +1,39 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package cgo + +import ( + "errors" + "fmt" + "go/build" + "os/exec" + "strings" +) + +// pkgConfig runs pkg-config with the specified arguments and returns the flags it prints. +func pkgConfig(mode string, pkgs []string) (flags []string, err error) { + cmd := exec.Command("pkg-config", append([]string{mode}, pkgs...)...) + out, err := cmd.CombinedOutput() + if err != nil { + s := fmt.Sprintf("%s failed: %v", strings.Join(cmd.Args, " "), err) + if len(out) > 0 { + s = fmt.Sprintf("%s: %s", s, out) + } + return nil, errors.New(s) + } + if len(out) > 0 { + flags = strings.Fields(string(out)) + } + return +} + +// pkgConfigFlags calls pkg-config if needed and returns the cflags +// needed to build the package. +func pkgConfigFlags(p *build.Package) (cflags []string, err error) { + if len(p.CgoPkgConfig) == 0 { + return nil, nil + } + return pkgConfig("--cflags", p.CgoPkgConfig) +} diff --git a/vendor/golang.org/x/tools/go/internal/gcimporter/bexport.go b/vendor/golang.org/x/tools/go/internal/gcimporter/bexport.go new file mode 100644 index 0000000000..9f65049140 --- /dev/null +++ b/vendor/golang.org/x/tools/go/internal/gcimporter/bexport.go @@ -0,0 +1,852 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Binary package export. +// This file was derived from $GOROOT/src/cmd/compile/internal/gc/bexport.go; +// see that file for specification of the format. + +package gcimporter + +import ( + "bytes" + "encoding/binary" + "fmt" + "go/ast" + "go/constant" + "go/token" + "go/types" + "math" + "math/big" + "sort" + "strings" +) + +// If debugFormat is set, each integer and string value is preceded by a marker +// and position information in the encoding. This mechanism permits an importer +// to recognize immediately when it is out of sync. The importer recognizes this +// mode automatically (i.e., it can import export data produced with debugging +// support even if debugFormat is not set at the time of import). This mode will +// lead to massively larger export data (by a factor of 2 to 3) and should only +// be enabled during development and debugging. +// +// NOTE: This flag is the first flag to enable if importing dies because of +// (suspected) format errors, and whenever a change is made to the format. +const debugFormat = false // default: false + +// If trace is set, debugging output is printed to std out. +const trace = false // default: false + +// Current export format version. Increase with each format change. +// Note: The latest binary (non-indexed) export format is at version 6. +// This exporter is still at level 4, but it doesn't matter since +// the binary importer can handle older versions just fine. +// 6: package height (CL 105038) -- NOT IMPLEMENTED HERE +// 5: improved position encoding efficiency (issue 20080, CL 41619) -- NOT IMPLEMEMTED HERE +// 4: type name objects support type aliases, uses aliasTag +// 3: Go1.8 encoding (same as version 2, aliasTag defined but never used) +// 2: removed unused bool in ODCL export (compiler only) +// 1: header format change (more regular), export package for _ struct fields +// 0: Go1.7 encoding +const exportVersion = 4 + +// trackAllTypes enables cycle tracking for all types, not just named +// types. The existing compiler invariants assume that unnamed types +// that are not completely set up are not used, or else there are spurious +// errors. +// If disabled, only named types are tracked, possibly leading to slightly +// less efficient encoding in rare cases. It also prevents the export of +// some corner-case type declarations (but those are not handled correctly +// with with the textual export format either). +// TODO(gri) enable and remove once issues caused by it are fixed +const trackAllTypes = false + +type exporter struct { + fset *token.FileSet + out bytes.Buffer + + // object -> index maps, indexed in order of serialization + strIndex map[string]int + pkgIndex map[*types.Package]int + typIndex map[types.Type]int + + // position encoding + posInfoFormat bool + prevFile string + prevLine int + + // debugging support + written int // bytes written + indent int // for trace +} + +// internalError represents an error generated inside this package. +type internalError string + +func (e internalError) Error() string { return "gcimporter: " + string(e) } + +func internalErrorf(format string, args ...interface{}) error { + return internalError(fmt.Sprintf(format, args...)) +} + +// BExportData returns binary export data for pkg. +// If no file set is provided, position info will be missing. +func BExportData(fset *token.FileSet, pkg *types.Package) (b []byte, err error) { + defer func() { + if e := recover(); e != nil { + if ierr, ok := e.(internalError); ok { + err = ierr + return + } + // Not an internal error; panic again. + panic(e) + } + }() + + p := exporter{ + fset: fset, + strIndex: map[string]int{"": 0}, // empty string is mapped to 0 + pkgIndex: make(map[*types.Package]int), + typIndex: make(map[types.Type]int), + posInfoFormat: true, // TODO(gri) might become a flag, eventually + } + + // write version info + // The version string must start with "version %d" where %d is the version + // number. Additional debugging information may follow after a blank; that + // text is ignored by the importer. + p.rawStringln(fmt.Sprintf("version %d", exportVersion)) + var debug string + if debugFormat { + debug = "debug" + } + p.rawStringln(debug) // cannot use p.bool since it's affected by debugFormat; also want to see this clearly + p.bool(trackAllTypes) + p.bool(p.posInfoFormat) + + // --- generic export data --- + + // populate type map with predeclared "known" types + for index, typ := range predeclared { + p.typIndex[typ] = index + } + if len(p.typIndex) != len(predeclared) { + return nil, internalError("duplicate entries in type map?") + } + + // write package data + p.pkg(pkg, true) + if trace { + p.tracef("\n") + } + + // write objects + objcount := 0 + scope := pkg.Scope() + for _, name := range scope.Names() { + if !ast.IsExported(name) { + continue + } + if trace { + p.tracef("\n") + } + p.obj(scope.Lookup(name)) + objcount++ + } + + // indicate end of list + if trace { + p.tracef("\n") + } + p.tag(endTag) + + // for self-verification only (redundant) + p.int(objcount) + + if trace { + p.tracef("\n") + } + + // --- end of export data --- + + return p.out.Bytes(), nil +} + +func (p *exporter) pkg(pkg *types.Package, emptypath bool) { + if pkg == nil { + panic(internalError("unexpected nil pkg")) + } + + // if we saw the package before, write its index (>= 0) + if i, ok := p.pkgIndex[pkg]; ok { + p.index('P', i) + return + } + + // otherwise, remember the package, write the package tag (< 0) and package data + if trace { + p.tracef("P%d = { ", len(p.pkgIndex)) + defer p.tracef("} ") + } + p.pkgIndex[pkg] = len(p.pkgIndex) + + p.tag(packageTag) + p.string(pkg.Name()) + if emptypath { + p.string("") + } else { + p.string(pkg.Path()) + } +} + +func (p *exporter) obj(obj types.Object) { + switch obj := obj.(type) { + case *types.Const: + p.tag(constTag) + p.pos(obj) + p.qualifiedName(obj) + p.typ(obj.Type()) + p.value(obj.Val()) + + case *types.TypeName: + if obj.IsAlias() { + p.tag(aliasTag) + p.pos(obj) + p.qualifiedName(obj) + } else { + p.tag(typeTag) + } + p.typ(obj.Type()) + + case *types.Var: + p.tag(varTag) + p.pos(obj) + p.qualifiedName(obj) + p.typ(obj.Type()) + + case *types.Func: + p.tag(funcTag) + p.pos(obj) + p.qualifiedName(obj) + sig := obj.Type().(*types.Signature) + p.paramList(sig.Params(), sig.Variadic()) + p.paramList(sig.Results(), false) + + default: + panic(internalErrorf("unexpected object %v (%T)", obj, obj)) + } +} + +func (p *exporter) pos(obj types.Object) { + if !p.posInfoFormat { + return + } + + file, line := p.fileLine(obj) + if file == p.prevFile { + // common case: write line delta + // delta == 0 means different file or no line change + delta := line - p.prevLine + p.int(delta) + if delta == 0 { + p.int(-1) // -1 means no file change + } + } else { + // different file + p.int(0) + // Encode filename as length of common prefix with previous + // filename, followed by (possibly empty) suffix. Filenames + // frequently share path prefixes, so this can save a lot + // of space and make export data size less dependent on file + // path length. The suffix is unlikely to be empty because + // file names tend to end in ".go". + n := commonPrefixLen(p.prevFile, file) + p.int(n) // n >= 0 + p.string(file[n:]) // write suffix only + p.prevFile = file + p.int(line) + } + p.prevLine = line +} + +func (p *exporter) fileLine(obj types.Object) (file string, line int) { + if p.fset != nil { + pos := p.fset.Position(obj.Pos()) + file = pos.Filename + line = pos.Line + } + return +} + +func commonPrefixLen(a, b string) int { + if len(a) > len(b) { + a, b = b, a + } + // len(a) <= len(b) + i := 0 + for i < len(a) && a[i] == b[i] { + i++ + } + return i +} + +func (p *exporter) qualifiedName(obj types.Object) { + p.string(obj.Name()) + p.pkg(obj.Pkg(), false) +} + +func (p *exporter) typ(t types.Type) { + if t == nil { + panic(internalError("nil type")) + } + + // Possible optimization: Anonymous pointer types *T where + // T is a named type are common. We could canonicalize all + // such types *T to a single type PT = *T. This would lead + // to at most one *T entry in typIndex, and all future *T's + // would be encoded as the respective index directly. Would + // save 1 byte (pointerTag) per *T and reduce the typIndex + // size (at the cost of a canonicalization map). We can do + // this later, without encoding format change. + + // if we saw the type before, write its index (>= 0) + if i, ok := p.typIndex[t]; ok { + p.index('T', i) + return + } + + // otherwise, remember the type, write the type tag (< 0) and type data + if trackAllTypes { + if trace { + p.tracef("T%d = {>\n", len(p.typIndex)) + defer p.tracef("<\n} ") + } + p.typIndex[t] = len(p.typIndex) + } + + switch t := t.(type) { + case *types.Named: + if !trackAllTypes { + // if we don't track all types, track named types now + p.typIndex[t] = len(p.typIndex) + } + + p.tag(namedTag) + p.pos(t.Obj()) + p.qualifiedName(t.Obj()) + p.typ(t.Underlying()) + if !types.IsInterface(t) { + p.assocMethods(t) + } + + case *types.Array: + p.tag(arrayTag) + p.int64(t.Len()) + p.typ(t.Elem()) + + case *types.Slice: + p.tag(sliceTag) + p.typ(t.Elem()) + + case *dddSlice: + p.tag(dddTag) + p.typ(t.elem) + + case *types.Struct: + p.tag(structTag) + p.fieldList(t) + + case *types.Pointer: + p.tag(pointerTag) + p.typ(t.Elem()) + + case *types.Signature: + p.tag(signatureTag) + p.paramList(t.Params(), t.Variadic()) + p.paramList(t.Results(), false) + + case *types.Interface: + p.tag(interfaceTag) + p.iface(t) + + case *types.Map: + p.tag(mapTag) + p.typ(t.Key()) + p.typ(t.Elem()) + + case *types.Chan: + p.tag(chanTag) + p.int(int(3 - t.Dir())) // hack + p.typ(t.Elem()) + + default: + panic(internalErrorf("unexpected type %T: %s", t, t)) + } +} + +func (p *exporter) assocMethods(named *types.Named) { + // Sort methods (for determinism). + var methods []*types.Func + for i := 0; i < named.NumMethods(); i++ { + methods = append(methods, named.Method(i)) + } + sort.Sort(methodsByName(methods)) + + p.int(len(methods)) + + if trace && methods != nil { + p.tracef("associated methods {>\n") + } + + for i, m := range methods { + if trace && i > 0 { + p.tracef("\n") + } + + p.pos(m) + name := m.Name() + p.string(name) + if !exported(name) { + p.pkg(m.Pkg(), false) + } + + sig := m.Type().(*types.Signature) + p.paramList(types.NewTuple(sig.Recv()), false) + p.paramList(sig.Params(), sig.Variadic()) + p.paramList(sig.Results(), false) + p.int(0) // dummy value for go:nointerface pragma - ignored by importer + } + + if trace && methods != nil { + p.tracef("<\n} ") + } +} + +type methodsByName []*types.Func + +func (x methodsByName) Len() int { return len(x) } +func (x methodsByName) Swap(i, j int) { x[i], x[j] = x[j], x[i] } +func (x methodsByName) Less(i, j int) bool { return x[i].Name() < x[j].Name() } + +func (p *exporter) fieldList(t *types.Struct) { + if trace && t.NumFields() > 0 { + p.tracef("fields {>\n") + defer p.tracef("<\n} ") + } + + p.int(t.NumFields()) + for i := 0; i < t.NumFields(); i++ { + if trace && i > 0 { + p.tracef("\n") + } + p.field(t.Field(i)) + p.string(t.Tag(i)) + } +} + +func (p *exporter) field(f *types.Var) { + if !f.IsField() { + panic(internalError("field expected")) + } + + p.pos(f) + p.fieldName(f) + p.typ(f.Type()) +} + +func (p *exporter) iface(t *types.Interface) { + // TODO(gri): enable importer to load embedded interfaces, + // then emit Embeddeds and ExplicitMethods separately here. + p.int(0) + + n := t.NumMethods() + if trace && n > 0 { + p.tracef("methods {>\n") + defer p.tracef("<\n} ") + } + p.int(n) + for i := 0; i < n; i++ { + if trace && i > 0 { + p.tracef("\n") + } + p.method(t.Method(i)) + } +} + +func (p *exporter) method(m *types.Func) { + sig := m.Type().(*types.Signature) + if sig.Recv() == nil { + panic(internalError("method expected")) + } + + p.pos(m) + p.string(m.Name()) + if m.Name() != "_" && !ast.IsExported(m.Name()) { + p.pkg(m.Pkg(), false) + } + + // interface method; no need to encode receiver. + p.paramList(sig.Params(), sig.Variadic()) + p.paramList(sig.Results(), false) +} + +func (p *exporter) fieldName(f *types.Var) { + name := f.Name() + + if f.Anonymous() { + // anonymous field - we distinguish between 3 cases: + // 1) field name matches base type name and is exported + // 2) field name matches base type name and is not exported + // 3) field name doesn't match base type name (alias name) + bname := basetypeName(f.Type()) + if name == bname { + if ast.IsExported(name) { + name = "" // 1) we don't need to know the field name or package + } else { + name = "?" // 2) use unexported name "?" to force package export + } + } else { + // 3) indicate alias and export name as is + // (this requires an extra "@" but this is a rare case) + p.string("@") + } + } + + p.string(name) + if name != "" && !ast.IsExported(name) { + p.pkg(f.Pkg(), false) + } +} + +func basetypeName(typ types.Type) string { + switch typ := deref(typ).(type) { + case *types.Basic: + return typ.Name() + case *types.Named: + return typ.Obj().Name() + default: + return "" // unnamed type + } +} + +func (p *exporter) paramList(params *types.Tuple, variadic bool) { + // use negative length to indicate unnamed parameters + // (look at the first parameter only since either all + // names are present or all are absent) + n := params.Len() + if n > 0 && params.At(0).Name() == "" { + n = -n + } + p.int(n) + for i := 0; i < params.Len(); i++ { + q := params.At(i) + t := q.Type() + if variadic && i == params.Len()-1 { + t = &dddSlice{t.(*types.Slice).Elem()} + } + p.typ(t) + if n > 0 { + name := q.Name() + p.string(name) + if name != "_" { + p.pkg(q.Pkg(), false) + } + } + p.string("") // no compiler-specific info + } +} + +func (p *exporter) value(x constant.Value) { + if trace { + p.tracef("= ") + } + + switch x.Kind() { + case constant.Bool: + tag := falseTag + if constant.BoolVal(x) { + tag = trueTag + } + p.tag(tag) + + case constant.Int: + if v, exact := constant.Int64Val(x); exact { + // common case: x fits into an int64 - use compact encoding + p.tag(int64Tag) + p.int64(v) + return + } + // uncommon case: large x - use float encoding + // (powers of 2 will be encoded efficiently with exponent) + p.tag(floatTag) + p.float(constant.ToFloat(x)) + + case constant.Float: + p.tag(floatTag) + p.float(x) + + case constant.Complex: + p.tag(complexTag) + p.float(constant.Real(x)) + p.float(constant.Imag(x)) + + case constant.String: + p.tag(stringTag) + p.string(constant.StringVal(x)) + + case constant.Unknown: + // package contains type errors + p.tag(unknownTag) + + default: + panic(internalErrorf("unexpected value %v (%T)", x, x)) + } +} + +func (p *exporter) float(x constant.Value) { + if x.Kind() != constant.Float { + panic(internalErrorf("unexpected constant %v, want float", x)) + } + // extract sign (there is no -0) + sign := constant.Sign(x) + if sign == 0 { + // x == 0 + p.int(0) + return + } + // x != 0 + + var f big.Float + if v, exact := constant.Float64Val(x); exact { + // float64 + f.SetFloat64(v) + } else if num, denom := constant.Num(x), constant.Denom(x); num.Kind() == constant.Int { + // TODO(gri): add big.Rat accessor to constant.Value. + r := valueToRat(num) + f.SetRat(r.Quo(r, valueToRat(denom))) + } else { + // Value too large to represent as a fraction => inaccessible. + // TODO(gri): add big.Float accessor to constant.Value. + f.SetFloat64(math.MaxFloat64) // FIXME + } + + // extract exponent such that 0.5 <= m < 1.0 + var m big.Float + exp := f.MantExp(&m) + + // extract mantissa as *big.Int + // - set exponent large enough so mant satisfies mant.IsInt() + // - get *big.Int from mant + m.SetMantExp(&m, int(m.MinPrec())) + mant, acc := m.Int(nil) + if acc != big.Exact { + panic(internalError("internal error")) + } + + p.int(sign) + p.int(exp) + p.string(string(mant.Bytes())) +} + +func valueToRat(x constant.Value) *big.Rat { + // Convert little-endian to big-endian. + // I can't believe this is necessary. + bytes := constant.Bytes(x) + for i := 0; i < len(bytes)/2; i++ { + bytes[i], bytes[len(bytes)-1-i] = bytes[len(bytes)-1-i], bytes[i] + } + return new(big.Rat).SetInt(new(big.Int).SetBytes(bytes)) +} + +func (p *exporter) bool(b bool) bool { + if trace { + p.tracef("[") + defer p.tracef("= %v] ", b) + } + + x := 0 + if b { + x = 1 + } + p.int(x) + return b +} + +// ---------------------------------------------------------------------------- +// Low-level encoders + +func (p *exporter) index(marker byte, index int) { + if index < 0 { + panic(internalError("invalid index < 0")) + } + if debugFormat { + p.marker('t') + } + if trace { + p.tracef("%c%d ", marker, index) + } + p.rawInt64(int64(index)) +} + +func (p *exporter) tag(tag int) { + if tag >= 0 { + panic(internalError("invalid tag >= 0")) + } + if debugFormat { + p.marker('t') + } + if trace { + p.tracef("%s ", tagString[-tag]) + } + p.rawInt64(int64(tag)) +} + +func (p *exporter) int(x int) { + p.int64(int64(x)) +} + +func (p *exporter) int64(x int64) { + if debugFormat { + p.marker('i') + } + if trace { + p.tracef("%d ", x) + } + p.rawInt64(x) +} + +func (p *exporter) string(s string) { + if debugFormat { + p.marker('s') + } + if trace { + p.tracef("%q ", s) + } + // if we saw the string before, write its index (>= 0) + // (the empty string is mapped to 0) + if i, ok := p.strIndex[s]; ok { + p.rawInt64(int64(i)) + return + } + // otherwise, remember string and write its negative length and bytes + p.strIndex[s] = len(p.strIndex) + p.rawInt64(-int64(len(s))) + for i := 0; i < len(s); i++ { + p.rawByte(s[i]) + } +} + +// marker emits a marker byte and position information which makes +// it easy for a reader to detect if it is "out of sync". Used for +// debugFormat format only. +func (p *exporter) marker(m byte) { + p.rawByte(m) + // Enable this for help tracking down the location + // of an incorrect marker when running in debugFormat. + if false && trace { + p.tracef("#%d ", p.written) + } + p.rawInt64(int64(p.written)) +} + +// rawInt64 should only be used by low-level encoders. +func (p *exporter) rawInt64(x int64) { + var tmp [binary.MaxVarintLen64]byte + n := binary.PutVarint(tmp[:], x) + for i := 0; i < n; i++ { + p.rawByte(tmp[i]) + } +} + +// rawStringln should only be used to emit the initial version string. +func (p *exporter) rawStringln(s string) { + for i := 0; i < len(s); i++ { + p.rawByte(s[i]) + } + p.rawByte('\n') +} + +// rawByte is the bottleneck interface to write to p.out. +// rawByte escapes b as follows (any encoding does that +// hides '$'): +// +// '$' => '|' 'S' +// '|' => '|' '|' +// +// Necessary so other tools can find the end of the +// export data by searching for "$$". +// rawByte should only be used by low-level encoders. +func (p *exporter) rawByte(b byte) { + switch b { + case '$': + // write '$' as '|' 'S' + b = 'S' + fallthrough + case '|': + // write '|' as '|' '|' + p.out.WriteByte('|') + p.written++ + } + p.out.WriteByte(b) + p.written++ +} + +// tracef is like fmt.Printf but it rewrites the format string +// to take care of indentation. +func (p *exporter) tracef(format string, args ...interface{}) { + if strings.ContainsAny(format, "<>\n") { + var buf bytes.Buffer + for i := 0; i < len(format); i++ { + // no need to deal with runes + ch := format[i] + switch ch { + case '>': + p.indent++ + continue + case '<': + p.indent-- + continue + } + buf.WriteByte(ch) + if ch == '\n' { + for j := p.indent; j > 0; j-- { + buf.WriteString(". ") + } + } + } + format = buf.String() + } + fmt.Printf(format, args...) +} + +// Debugging support. +// (tagString is only used when tracing is enabled) +var tagString = [...]string{ + // Packages + -packageTag: "package", + + // Types + -namedTag: "named type", + -arrayTag: "array", + -sliceTag: "slice", + -dddTag: "ddd", + -structTag: "struct", + -pointerTag: "pointer", + -signatureTag: "signature", + -interfaceTag: "interface", + -mapTag: "map", + -chanTag: "chan", + + // Values + -falseTag: "false", + -trueTag: "true", + -int64Tag: "int64", + -floatTag: "float", + -fractionTag: "fraction", + -complexTag: "complex", + -stringTag: "string", + -unknownTag: "unknown", + + // Type aliases + -aliasTag: "alias", +} diff --git a/vendor/golang.org/x/tools/go/internal/gcimporter/bimport.go b/vendor/golang.org/x/tools/go/internal/gcimporter/bimport.go new file mode 100644 index 0000000000..b31eacfc0f --- /dev/null +++ b/vendor/golang.org/x/tools/go/internal/gcimporter/bimport.go @@ -0,0 +1,1028 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file is a copy of $GOROOT/src/go/internal/gcimporter/bimport.go. + +package gcimporter + +import ( + "encoding/binary" + "fmt" + "go/constant" + "go/token" + "go/types" + "sort" + "strconv" + "strings" + "sync" + "unicode" + "unicode/utf8" +) + +type importer struct { + imports map[string]*types.Package + data []byte + importpath string + buf []byte // for reading strings + version int // export format version + + // object lists + strList []string // in order of appearance + pathList []string // in order of appearance + pkgList []*types.Package // in order of appearance + typList []types.Type // in order of appearance + interfaceList []*types.Interface // for delayed completion only + trackAllTypes bool + + // position encoding + posInfoFormat bool + prevFile string + prevLine int + fake fakeFileSet + + // debugging support + debugFormat bool + read int // bytes read +} + +// BImportData imports a package from the serialized package data +// and returns the number of bytes consumed and a reference to the package. +// If the export data version is not recognized or the format is otherwise +// compromised, an error is returned. +func BImportData(fset *token.FileSet, imports map[string]*types.Package, data []byte, path string) (_ int, pkg *types.Package, err error) { + // catch panics and return them as errors + const currentVersion = 6 + version := -1 // unknown version + defer func() { + if e := recover(); e != nil { + // Return a (possibly nil or incomplete) package unchanged (see #16088). + if version > currentVersion { + err = fmt.Errorf("cannot import %q (%v), export data is newer version - update tool", path, e) + } else { + err = fmt.Errorf("cannot import %q (%v), possibly version skew - reinstall package", path, e) + } + } + }() + + p := importer{ + imports: imports, + data: data, + importpath: path, + version: version, + strList: []string{""}, // empty string is mapped to 0 + pathList: []string{""}, // empty string is mapped to 0 + fake: fakeFileSet{ + fset: fset, + files: make(map[string]*token.File), + }, + } + + // read version info + var versionstr string + if b := p.rawByte(); b == 'c' || b == 'd' { + // Go1.7 encoding; first byte encodes low-level + // encoding format (compact vs debug). + // For backward-compatibility only (avoid problems with + // old installed packages). Newly compiled packages use + // the extensible format string. + // TODO(gri) Remove this support eventually; after Go1.8. + if b == 'd' { + p.debugFormat = true + } + p.trackAllTypes = p.rawByte() == 'a' + p.posInfoFormat = p.int() != 0 + versionstr = p.string() + if versionstr == "v1" { + version = 0 + } + } else { + // Go1.8 extensible encoding + // read version string and extract version number (ignore anything after the version number) + versionstr = p.rawStringln(b) + if s := strings.SplitN(versionstr, " ", 3); len(s) >= 2 && s[0] == "version" { + if v, err := strconv.Atoi(s[1]); err == nil && v > 0 { + version = v + } + } + } + p.version = version + + // read version specific flags - extend as necessary + switch p.version { + // case currentVersion: + // ... + // fallthrough + case currentVersion, 5, 4, 3, 2, 1: + p.debugFormat = p.rawStringln(p.rawByte()) == "debug" + p.trackAllTypes = p.int() != 0 + p.posInfoFormat = p.int() != 0 + case 0: + // Go1.7 encoding format - nothing to do here + default: + errorf("unknown bexport format version %d (%q)", p.version, versionstr) + } + + // --- generic export data --- + + // populate typList with predeclared "known" types + p.typList = append(p.typList, predeclared...) + + // read package data + pkg = p.pkg() + + // read objects of phase 1 only (see cmd/compile/internal/gc/bexport.go) + objcount := 0 + for { + tag := p.tagOrIndex() + if tag == endTag { + break + } + p.obj(tag) + objcount++ + } + + // self-verification + if count := p.int(); count != objcount { + errorf("got %d objects; want %d", objcount, count) + } + + // ignore compiler-specific import data + + // complete interfaces + // TODO(gri) re-investigate if we still need to do this in a delayed fashion + for _, typ := range p.interfaceList { + typ.Complete() + } + + // record all referenced packages as imports + list := append(([]*types.Package)(nil), p.pkgList[1:]...) + sort.Sort(byPath(list)) + pkg.SetImports(list) + + // package was imported completely and without errors + pkg.MarkComplete() + + return p.read, pkg, nil +} + +func errorf(format string, args ...interface{}) { + panic(fmt.Sprintf(format, args...)) +} + +func (p *importer) pkg() *types.Package { + // if the package was seen before, i is its index (>= 0) + i := p.tagOrIndex() + if i >= 0 { + return p.pkgList[i] + } + + // otherwise, i is the package tag (< 0) + if i != packageTag { + errorf("unexpected package tag %d version %d", i, p.version) + } + + // read package data + name := p.string() + var path string + if p.version >= 5 { + path = p.path() + } else { + path = p.string() + } + if p.version >= 6 { + p.int() // package height; unused by go/types + } + + // we should never see an empty package name + if name == "" { + errorf("empty package name in import") + } + + // an empty path denotes the package we are currently importing; + // it must be the first package we see + if (path == "") != (len(p.pkgList) == 0) { + errorf("package path %q for pkg index %d", path, len(p.pkgList)) + } + + // if the package was imported before, use that one; otherwise create a new one + if path == "" { + path = p.importpath + } + pkg := p.imports[path] + if pkg == nil { + pkg = types.NewPackage(path, name) + p.imports[path] = pkg + } else if pkg.Name() != name { + errorf("conflicting names %s and %s for package %q", pkg.Name(), name, path) + } + p.pkgList = append(p.pkgList, pkg) + + return pkg +} + +// objTag returns the tag value for each object kind. +func objTag(obj types.Object) int { + switch obj.(type) { + case *types.Const: + return constTag + case *types.TypeName: + return typeTag + case *types.Var: + return varTag + case *types.Func: + return funcTag + default: + errorf("unexpected object: %v (%T)", obj, obj) // panics + panic("unreachable") + } +} + +func sameObj(a, b types.Object) bool { + // Because unnamed types are not canonicalized, we cannot simply compare types for + // (pointer) identity. + // Ideally we'd check equality of constant values as well, but this is good enough. + return objTag(a) == objTag(b) && types.Identical(a.Type(), b.Type()) +} + +func (p *importer) declare(obj types.Object) { + pkg := obj.Pkg() + if alt := pkg.Scope().Insert(obj); alt != nil { + // This can only trigger if we import a (non-type) object a second time. + // Excluding type aliases, this cannot happen because 1) we only import a package + // once; and b) we ignore compiler-specific export data which may contain + // functions whose inlined function bodies refer to other functions that + // were already imported. + // However, type aliases require reexporting the original type, so we need + // to allow it (see also the comment in cmd/compile/internal/gc/bimport.go, + // method importer.obj, switch case importing functions). + // TODO(gri) review/update this comment once the gc compiler handles type aliases. + if !sameObj(obj, alt) { + errorf("inconsistent import:\n\t%v\npreviously imported as:\n\t%v\n", obj, alt) + } + } +} + +func (p *importer) obj(tag int) { + switch tag { + case constTag: + pos := p.pos() + pkg, name := p.qualifiedName() + typ := p.typ(nil, nil) + val := p.value() + p.declare(types.NewConst(pos, pkg, name, typ, val)) + + case aliasTag: + // TODO(gri) verify type alias hookup is correct + pos := p.pos() + pkg, name := p.qualifiedName() + typ := p.typ(nil, nil) + p.declare(types.NewTypeName(pos, pkg, name, typ)) + + case typeTag: + p.typ(nil, nil) + + case varTag: + pos := p.pos() + pkg, name := p.qualifiedName() + typ := p.typ(nil, nil) + p.declare(types.NewVar(pos, pkg, name, typ)) + + case funcTag: + pos := p.pos() + pkg, name := p.qualifiedName() + params, isddd := p.paramList() + result, _ := p.paramList() + sig := types.NewSignature(nil, params, result, isddd) + p.declare(types.NewFunc(pos, pkg, name, sig)) + + default: + errorf("unexpected object tag %d", tag) + } +} + +const deltaNewFile = -64 // see cmd/compile/internal/gc/bexport.go + +func (p *importer) pos() token.Pos { + if !p.posInfoFormat { + return token.NoPos + } + + file := p.prevFile + line := p.prevLine + delta := p.int() + line += delta + if p.version >= 5 { + if delta == deltaNewFile { + if n := p.int(); n >= 0 { + // file changed + file = p.path() + line = n + } + } + } else { + if delta == 0 { + if n := p.int(); n >= 0 { + // file changed + file = p.prevFile[:n] + p.string() + line = p.int() + } + } + } + p.prevFile = file + p.prevLine = line + + return p.fake.pos(file, line) +} + +// Synthesize a token.Pos +type fakeFileSet struct { + fset *token.FileSet + files map[string]*token.File +} + +func (s *fakeFileSet) pos(file string, line int) token.Pos { + // Since we don't know the set of needed file positions, we + // reserve maxlines positions per file. + const maxlines = 64 * 1024 + f := s.files[file] + if f == nil { + f = s.fset.AddFile(file, -1, maxlines) + s.files[file] = f + // Allocate the fake linebreak indices on first use. + // TODO(adonovan): opt: save ~512KB using a more complex scheme? + fakeLinesOnce.Do(func() { + fakeLines = make([]int, maxlines) + for i := range fakeLines { + fakeLines[i] = i + } + }) + f.SetLines(fakeLines) + } + + if line > maxlines { + line = 1 + } + + // Treat the file as if it contained only newlines + // and column=1: use the line number as the offset. + return f.Pos(line - 1) +} + +var ( + fakeLines []int + fakeLinesOnce sync.Once +) + +func (p *importer) qualifiedName() (pkg *types.Package, name string) { + name = p.string() + pkg = p.pkg() + return +} + +func (p *importer) record(t types.Type) { + p.typList = append(p.typList, t) +} + +// A dddSlice is a types.Type representing ...T parameters. +// It only appears for parameter types and does not escape +// the importer. +type dddSlice struct { + elem types.Type +} + +func (t *dddSlice) Underlying() types.Type { return t } +func (t *dddSlice) String() string { return "..." + t.elem.String() } + +// parent is the package which declared the type; parent == nil means +// the package currently imported. The parent package is needed for +// exported struct fields and interface methods which don't contain +// explicit package information in the export data. +// +// A non-nil tname is used as the "owner" of the result type; i.e., +// the result type is the underlying type of tname. tname is used +// to give interface methods a named receiver type where possible. +func (p *importer) typ(parent *types.Package, tname *types.Named) types.Type { + // if the type was seen before, i is its index (>= 0) + i := p.tagOrIndex() + if i >= 0 { + return p.typList[i] + } + + // otherwise, i is the type tag (< 0) + switch i { + case namedTag: + // read type object + pos := p.pos() + parent, name := p.qualifiedName() + scope := parent.Scope() + obj := scope.Lookup(name) + + // if the object doesn't exist yet, create and insert it + if obj == nil { + obj = types.NewTypeName(pos, parent, name, nil) + scope.Insert(obj) + } + + if _, ok := obj.(*types.TypeName); !ok { + errorf("pkg = %s, name = %s => %s", parent, name, obj) + } + + // associate new named type with obj if it doesn't exist yet + t0 := types.NewNamed(obj.(*types.TypeName), nil, nil) + + // but record the existing type, if any + tname := obj.Type().(*types.Named) // tname is either t0 or the existing type + p.record(tname) + + // read underlying type + t0.SetUnderlying(p.typ(parent, t0)) + + // interfaces don't have associated methods + if types.IsInterface(t0) { + return tname + } + + // read associated methods + for i := p.int(); i > 0; i-- { + // TODO(gri) replace this with something closer to fieldName + pos := p.pos() + name := p.string() + if !exported(name) { + p.pkg() + } + + recv, _ := p.paramList() // TODO(gri) do we need a full param list for the receiver? + params, isddd := p.paramList() + result, _ := p.paramList() + p.int() // go:nointerface pragma - discarded + + sig := types.NewSignature(recv.At(0), params, result, isddd) + t0.AddMethod(types.NewFunc(pos, parent, name, sig)) + } + + return tname + + case arrayTag: + t := new(types.Array) + if p.trackAllTypes { + p.record(t) + } + + n := p.int64() + *t = *types.NewArray(p.typ(parent, nil), n) + return t + + case sliceTag: + t := new(types.Slice) + if p.trackAllTypes { + p.record(t) + } + + *t = *types.NewSlice(p.typ(parent, nil)) + return t + + case dddTag: + t := new(dddSlice) + if p.trackAllTypes { + p.record(t) + } + + t.elem = p.typ(parent, nil) + return t + + case structTag: + t := new(types.Struct) + if p.trackAllTypes { + p.record(t) + } + + *t = *types.NewStruct(p.fieldList(parent)) + return t + + case pointerTag: + t := new(types.Pointer) + if p.trackAllTypes { + p.record(t) + } + + *t = *types.NewPointer(p.typ(parent, nil)) + return t + + case signatureTag: + t := new(types.Signature) + if p.trackAllTypes { + p.record(t) + } + + params, isddd := p.paramList() + result, _ := p.paramList() + *t = *types.NewSignature(nil, params, result, isddd) + return t + + case interfaceTag: + // Create a dummy entry in the type list. This is safe because we + // cannot expect the interface type to appear in a cycle, as any + // such cycle must contain a named type which would have been + // first defined earlier. + // TODO(gri) Is this still true now that we have type aliases? + // See issue #23225. + n := len(p.typList) + if p.trackAllTypes { + p.record(nil) + } + + var embeddeds []types.Type + for n := p.int(); n > 0; n-- { + p.pos() + embeddeds = append(embeddeds, p.typ(parent, nil)) + } + + t := newInterface(p.methodList(parent, tname), embeddeds) + p.interfaceList = append(p.interfaceList, t) + if p.trackAllTypes { + p.typList[n] = t + } + return t + + case mapTag: + t := new(types.Map) + if p.trackAllTypes { + p.record(t) + } + + key := p.typ(parent, nil) + val := p.typ(parent, nil) + *t = *types.NewMap(key, val) + return t + + case chanTag: + t := new(types.Chan) + if p.trackAllTypes { + p.record(t) + } + + dir := chanDir(p.int()) + val := p.typ(parent, nil) + *t = *types.NewChan(dir, val) + return t + + default: + errorf("unexpected type tag %d", i) // panics + panic("unreachable") + } +} + +func chanDir(d int) types.ChanDir { + // tag values must match the constants in cmd/compile/internal/gc/go.go + switch d { + case 1 /* Crecv */ : + return types.RecvOnly + case 2 /* Csend */ : + return types.SendOnly + case 3 /* Cboth */ : + return types.SendRecv + default: + errorf("unexpected channel dir %d", d) + return 0 + } +} + +func (p *importer) fieldList(parent *types.Package) (fields []*types.Var, tags []string) { + if n := p.int(); n > 0 { + fields = make([]*types.Var, n) + tags = make([]string, n) + for i := range fields { + fields[i], tags[i] = p.field(parent) + } + } + return +} + +func (p *importer) field(parent *types.Package) (*types.Var, string) { + pos := p.pos() + pkg, name, alias := p.fieldName(parent) + typ := p.typ(parent, nil) + tag := p.string() + + anonymous := false + if name == "" { + // anonymous field - typ must be T or *T and T must be a type name + switch typ := deref(typ).(type) { + case *types.Basic: // basic types are named types + pkg = nil // // objects defined in Universe scope have no package + name = typ.Name() + case *types.Named: + name = typ.Obj().Name() + default: + errorf("named base type expected") + } + anonymous = true + } else if alias { + // anonymous field: we have an explicit name because it's an alias + anonymous = true + } + + return types.NewField(pos, pkg, name, typ, anonymous), tag +} + +func (p *importer) methodList(parent *types.Package, baseType *types.Named) (methods []*types.Func) { + if n := p.int(); n > 0 { + methods = make([]*types.Func, n) + for i := range methods { + methods[i] = p.method(parent, baseType) + } + } + return +} + +func (p *importer) method(parent *types.Package, baseType *types.Named) *types.Func { + pos := p.pos() + pkg, name, _ := p.fieldName(parent) + // If we don't have a baseType, use a nil receiver. + // A receiver using the actual interface type (which + // we don't know yet) will be filled in when we call + // types.Interface.Complete. + var recv *types.Var + if baseType != nil { + recv = types.NewVar(token.NoPos, parent, "", baseType) + } + params, isddd := p.paramList() + result, _ := p.paramList() + sig := types.NewSignature(recv, params, result, isddd) + return types.NewFunc(pos, pkg, name, sig) +} + +func (p *importer) fieldName(parent *types.Package) (pkg *types.Package, name string, alias bool) { + name = p.string() + pkg = parent + if pkg == nil { + // use the imported package instead + pkg = p.pkgList[0] + } + if p.version == 0 && name == "_" { + // version 0 didn't export a package for _ fields + return + } + switch name { + case "": + // 1) field name matches base type name and is exported: nothing to do + case "?": + // 2) field name matches base type name and is not exported: need package + name = "" + pkg = p.pkg() + case "@": + // 3) field name doesn't match type name (alias) + name = p.string() + alias = true + fallthrough + default: + if !exported(name) { + pkg = p.pkg() + } + } + return +} + +func (p *importer) paramList() (*types.Tuple, bool) { + n := p.int() + if n == 0 { + return nil, false + } + // negative length indicates unnamed parameters + named := true + if n < 0 { + n = -n + named = false + } + // n > 0 + params := make([]*types.Var, n) + isddd := false + for i := range params { + params[i], isddd = p.param(named) + } + return types.NewTuple(params...), isddd +} + +func (p *importer) param(named bool) (*types.Var, bool) { + t := p.typ(nil, nil) + td, isddd := t.(*dddSlice) + if isddd { + t = types.NewSlice(td.elem) + } + + var pkg *types.Package + var name string + if named { + name = p.string() + if name == "" { + errorf("expected named parameter") + } + if name != "_" { + pkg = p.pkg() + } + if i := strings.Index(name, "·"); i > 0 { + name = name[:i] // cut off gc-specific parameter numbering + } + } + + // read and discard compiler-specific info + p.string() + + return types.NewVar(token.NoPos, pkg, name, t), isddd +} + +func exported(name string) bool { + ch, _ := utf8.DecodeRuneInString(name) + return unicode.IsUpper(ch) +} + +func (p *importer) value() constant.Value { + switch tag := p.tagOrIndex(); tag { + case falseTag: + return constant.MakeBool(false) + case trueTag: + return constant.MakeBool(true) + case int64Tag: + return constant.MakeInt64(p.int64()) + case floatTag: + return p.float() + case complexTag: + re := p.float() + im := p.float() + return constant.BinaryOp(re, token.ADD, constant.MakeImag(im)) + case stringTag: + return constant.MakeString(p.string()) + case unknownTag: + return constant.MakeUnknown() + default: + errorf("unexpected value tag %d", tag) // panics + panic("unreachable") + } +} + +func (p *importer) float() constant.Value { + sign := p.int() + if sign == 0 { + return constant.MakeInt64(0) + } + + exp := p.int() + mant := []byte(p.string()) // big endian + + // remove leading 0's if any + for len(mant) > 0 && mant[0] == 0 { + mant = mant[1:] + } + + // convert to little endian + // TODO(gri) go/constant should have a more direct conversion function + // (e.g., once it supports a big.Float based implementation) + for i, j := 0, len(mant)-1; i < j; i, j = i+1, j-1 { + mant[i], mant[j] = mant[j], mant[i] + } + + // adjust exponent (constant.MakeFromBytes creates an integer value, + // but mant represents the mantissa bits such that 0.5 <= mant < 1.0) + exp -= len(mant) << 3 + if len(mant) > 0 { + for msd := mant[len(mant)-1]; msd&0x80 == 0; msd <<= 1 { + exp++ + } + } + + x := constant.MakeFromBytes(mant) + switch { + case exp < 0: + d := constant.Shift(constant.MakeInt64(1), token.SHL, uint(-exp)) + x = constant.BinaryOp(x, token.QUO, d) + case exp > 0: + x = constant.Shift(x, token.SHL, uint(exp)) + } + + if sign < 0 { + x = constant.UnaryOp(token.SUB, x, 0) + } + return x +} + +// ---------------------------------------------------------------------------- +// Low-level decoders + +func (p *importer) tagOrIndex() int { + if p.debugFormat { + p.marker('t') + } + + return int(p.rawInt64()) +} + +func (p *importer) int() int { + x := p.int64() + if int64(int(x)) != x { + errorf("exported integer too large") + } + return int(x) +} + +func (p *importer) int64() int64 { + if p.debugFormat { + p.marker('i') + } + + return p.rawInt64() +} + +func (p *importer) path() string { + if p.debugFormat { + p.marker('p') + } + // if the path was seen before, i is its index (>= 0) + // (the empty string is at index 0) + i := p.rawInt64() + if i >= 0 { + return p.pathList[i] + } + // otherwise, i is the negative path length (< 0) + a := make([]string, -i) + for n := range a { + a[n] = p.string() + } + s := strings.Join(a, "/") + p.pathList = append(p.pathList, s) + return s +} + +func (p *importer) string() string { + if p.debugFormat { + p.marker('s') + } + // if the string was seen before, i is its index (>= 0) + // (the empty string is at index 0) + i := p.rawInt64() + if i >= 0 { + return p.strList[i] + } + // otherwise, i is the negative string length (< 0) + if n := int(-i); n <= cap(p.buf) { + p.buf = p.buf[:n] + } else { + p.buf = make([]byte, n) + } + for i := range p.buf { + p.buf[i] = p.rawByte() + } + s := string(p.buf) + p.strList = append(p.strList, s) + return s +} + +func (p *importer) marker(want byte) { + if got := p.rawByte(); got != want { + errorf("incorrect marker: got %c; want %c (pos = %d)", got, want, p.read) + } + + pos := p.read + if n := int(p.rawInt64()); n != pos { + errorf("incorrect position: got %d; want %d", n, pos) + } +} + +// rawInt64 should only be used by low-level decoders. +func (p *importer) rawInt64() int64 { + i, err := binary.ReadVarint(p) + if err != nil { + errorf("read error: %v", err) + } + return i +} + +// rawStringln should only be used to read the initial version string. +func (p *importer) rawStringln(b byte) string { + p.buf = p.buf[:0] + for b != '\n' { + p.buf = append(p.buf, b) + b = p.rawByte() + } + return string(p.buf) +} + +// needed for binary.ReadVarint in rawInt64 +func (p *importer) ReadByte() (byte, error) { + return p.rawByte(), nil +} + +// byte is the bottleneck interface for reading p.data. +// It unescapes '|' 'S' to '$' and '|' '|' to '|'. +// rawByte should only be used by low-level decoders. +func (p *importer) rawByte() byte { + b := p.data[0] + r := 1 + if b == '|' { + b = p.data[1] + r = 2 + switch b { + case 'S': + b = '$' + case '|': + // nothing to do + default: + errorf("unexpected escape sequence in export data") + } + } + p.data = p.data[r:] + p.read += r + return b + +} + +// ---------------------------------------------------------------------------- +// Export format + +// Tags. Must be < 0. +const ( + // Objects + packageTag = -(iota + 1) + constTag + typeTag + varTag + funcTag + endTag + + // Types + namedTag + arrayTag + sliceTag + dddTag + structTag + pointerTag + signatureTag + interfaceTag + mapTag + chanTag + + // Values + falseTag + trueTag + int64Tag + floatTag + fractionTag // not used by gc + complexTag + stringTag + nilTag // only used by gc (appears in exported inlined function bodies) + unknownTag // not used by gc (only appears in packages with errors) + + // Type aliases + aliasTag +) + +var predeclared = []types.Type{ + // basic types + types.Typ[types.Bool], + types.Typ[types.Int], + types.Typ[types.Int8], + types.Typ[types.Int16], + types.Typ[types.Int32], + types.Typ[types.Int64], + types.Typ[types.Uint], + types.Typ[types.Uint8], + types.Typ[types.Uint16], + types.Typ[types.Uint32], + types.Typ[types.Uint64], + types.Typ[types.Uintptr], + types.Typ[types.Float32], + types.Typ[types.Float64], + types.Typ[types.Complex64], + types.Typ[types.Complex128], + types.Typ[types.String], + + // basic type aliases + types.Universe.Lookup("byte").Type(), + types.Universe.Lookup("rune").Type(), + + // error + types.Universe.Lookup("error").Type(), + + // untyped types + types.Typ[types.UntypedBool], + types.Typ[types.UntypedInt], + types.Typ[types.UntypedRune], + types.Typ[types.UntypedFloat], + types.Typ[types.UntypedComplex], + types.Typ[types.UntypedString], + types.Typ[types.UntypedNil], + + // package unsafe + types.Typ[types.UnsafePointer], + + // invalid type + types.Typ[types.Invalid], // only appears in packages with errors + + // used internally by gc; never used by this package or in .a files + anyType{}, +} + +type anyType struct{} + +func (t anyType) Underlying() types.Type { return t } +func (t anyType) String() string { return "any" } diff --git a/vendor/golang.org/x/tools/go/internal/gcimporter/exportdata.go b/vendor/golang.org/x/tools/go/internal/gcimporter/exportdata.go new file mode 100644 index 0000000000..f33dc5613e --- /dev/null +++ b/vendor/golang.org/x/tools/go/internal/gcimporter/exportdata.go @@ -0,0 +1,93 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file is a copy of $GOROOT/src/go/internal/gcimporter/exportdata.go. + +// This file implements FindExportData. + +package gcimporter + +import ( + "bufio" + "fmt" + "io" + "strconv" + "strings" +) + +func readGopackHeader(r *bufio.Reader) (name string, size int, err error) { + // See $GOROOT/include/ar.h. + hdr := make([]byte, 16+12+6+6+8+10+2) + _, err = io.ReadFull(r, hdr) + if err != nil { + return + } + // leave for debugging + if false { + fmt.Printf("header: %s", hdr) + } + s := strings.TrimSpace(string(hdr[16+12+6+6+8:][:10])) + size, err = strconv.Atoi(s) + if err != nil || hdr[len(hdr)-2] != '`' || hdr[len(hdr)-1] != '\n' { + err = fmt.Errorf("invalid archive header") + return + } + name = strings.TrimSpace(string(hdr[:16])) + return +} + +// FindExportData positions the reader r at the beginning of the +// export data section of an underlying GC-created object/archive +// file by reading from it. The reader must be positioned at the +// start of the file before calling this function. The hdr result +// is the string before the export data, either "$$" or "$$B". +// +func FindExportData(r *bufio.Reader) (hdr string, err error) { + // Read first line to make sure this is an object file. + line, err := r.ReadSlice('\n') + if err != nil { + err = fmt.Errorf("can't find export data (%v)", err) + return + } + + if string(line) == "!\n" { + // Archive file. Scan to __.PKGDEF. + var name string + if name, _, err = readGopackHeader(r); err != nil { + return + } + + // First entry should be __.PKGDEF. + if name != "__.PKGDEF" { + err = fmt.Errorf("go archive is missing __.PKGDEF") + return + } + + // Read first line of __.PKGDEF data, so that line + // is once again the first line of the input. + if line, err = r.ReadSlice('\n'); err != nil { + err = fmt.Errorf("can't find export data (%v)", err) + return + } + } + + // Now at __.PKGDEF in archive or still at beginning of file. + // Either way, line should begin with "go object ". + if !strings.HasPrefix(string(line), "go object ") { + err = fmt.Errorf("not a Go object file") + return + } + + // Skip over object header to export data. + // Begins after first line starting with $$. + for line[0] != '$' { + if line, err = r.ReadSlice('\n'); err != nil { + err = fmt.Errorf("can't find export data (%v)", err) + return + } + } + hdr = string(line) + + return +} diff --git a/vendor/golang.org/x/tools/go/internal/gcimporter/gcimporter.go b/vendor/golang.org/x/tools/go/internal/gcimporter/gcimporter.go new file mode 100644 index 0000000000..9cf186605f --- /dev/null +++ b/vendor/golang.org/x/tools/go/internal/gcimporter/gcimporter.go @@ -0,0 +1,1078 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file is a modified copy of $GOROOT/src/go/internal/gcimporter/gcimporter.go, +// but it also contains the original source-based importer code for Go1.6. +// Once we stop supporting 1.6, we can remove that code. + +// Package gcimporter provides various functions for reading +// gc-generated object files that can be used to implement the +// Importer interface defined by the Go 1.5 standard library package. +package gcimporter // import "golang.org/x/tools/go/internal/gcimporter" + +import ( + "bufio" + "errors" + "fmt" + "go/build" + "go/constant" + "go/token" + "go/types" + "io" + "io/ioutil" + "os" + "path/filepath" + "sort" + "strconv" + "strings" + "text/scanner" +) + +// debugging/development support +const debug = false + +var pkgExts = [...]string{".a", ".o"} + +// FindPkg returns the filename and unique package id for an import +// path based on package information provided by build.Import (using +// the build.Default build.Context). A relative srcDir is interpreted +// relative to the current working directory. +// If no file was found, an empty filename is returned. +// +func FindPkg(path, srcDir string) (filename, id string) { + if path == "" { + return + } + + var noext string + switch { + default: + // "x" -> "$GOPATH/pkg/$GOOS_$GOARCH/x.ext", "x" + // Don't require the source files to be present. + if abs, err := filepath.Abs(srcDir); err == nil { // see issue 14282 + srcDir = abs + } + bp, _ := build.Import(path, srcDir, build.FindOnly|build.AllowBinary) + if bp.PkgObj == "" { + id = path // make sure we have an id to print in error message + return + } + noext = strings.TrimSuffix(bp.PkgObj, ".a") + id = bp.ImportPath + + case build.IsLocalImport(path): + // "./x" -> "/this/directory/x.ext", "/this/directory/x" + noext = filepath.Join(srcDir, path) + id = noext + + case filepath.IsAbs(path): + // for completeness only - go/build.Import + // does not support absolute imports + // "/x" -> "/x.ext", "/x" + noext = path + id = path + } + + if false { // for debugging + if path != id { + fmt.Printf("%s -> %s\n", path, id) + } + } + + // try extensions + for _, ext := range pkgExts { + filename = noext + ext + if f, err := os.Stat(filename); err == nil && !f.IsDir() { + return + } + } + + filename = "" // not found + return +} + +// ImportData imports a package by reading the gc-generated export data, +// adds the corresponding package object to the packages map indexed by id, +// and returns the object. +// +// The packages map must contains all packages already imported. The data +// reader position must be the beginning of the export data section. The +// filename is only used in error messages. +// +// If packages[id] contains the completely imported package, that package +// can be used directly, and there is no need to call this function (but +// there is also no harm but for extra time used). +// +func ImportData(packages map[string]*types.Package, filename, id string, data io.Reader) (pkg *types.Package, err error) { + // support for parser error handling + defer func() { + switch r := recover().(type) { + case nil: + // nothing to do + case importError: + err = r + default: + panic(r) // internal error + } + }() + + var p parser + p.init(filename, id, data, packages) + pkg = p.parseExport() + + return +} + +// Import imports a gc-generated package given its import path and srcDir, adds +// the corresponding package object to the packages map, and returns the object. +// The packages map must contain all packages already imported. +// +func Import(packages map[string]*types.Package, path, srcDir string, lookup func(path string) (io.ReadCloser, error)) (pkg *types.Package, err error) { + var rc io.ReadCloser + var filename, id string + if lookup != nil { + // With custom lookup specified, assume that caller has + // converted path to a canonical import path for use in the map. + if path == "unsafe" { + return types.Unsafe, nil + } + id = path + + // No need to re-import if the package was imported completely before. + if pkg = packages[id]; pkg != nil && pkg.Complete() { + return + } + f, err := lookup(path) + if err != nil { + return nil, err + } + rc = f + } else { + filename, id = FindPkg(path, srcDir) + if filename == "" { + if path == "unsafe" { + return types.Unsafe, nil + } + return nil, fmt.Errorf("can't find import: %q", id) + } + + // no need to re-import if the package was imported completely before + if pkg = packages[id]; pkg != nil && pkg.Complete() { + return + } + + // open file + f, err := os.Open(filename) + if err != nil { + return nil, err + } + defer func() { + if err != nil { + // add file name to error + err = fmt.Errorf("%s: %v", filename, err) + } + }() + rc = f + } + defer rc.Close() + + var hdr string + buf := bufio.NewReader(rc) + if hdr, err = FindExportData(buf); err != nil { + return + } + + switch hdr { + case "$$\n": + // Work-around if we don't have a filename; happens only if lookup != nil. + // Either way, the filename is only needed for importer error messages, so + // this is fine. + if filename == "" { + filename = path + } + return ImportData(packages, filename, id, buf) + + case "$$B\n": + var data []byte + data, err = ioutil.ReadAll(buf) + if err != nil { + break + } + + // TODO(gri): allow clients of go/importer to provide a FileSet. + // Or, define a new standard go/types/gcexportdata package. + fset := token.NewFileSet() + + // The indexed export format starts with an 'i'; the older + // binary export format starts with a 'c', 'd', or 'v' + // (from "version"). Select appropriate importer. + if len(data) > 0 && data[0] == 'i' { + _, pkg, err = IImportData(fset, packages, data[1:], id) + } else { + _, pkg, err = BImportData(fset, packages, data, id) + } + + default: + err = fmt.Errorf("unknown export data header: %q", hdr) + } + + return +} + +// ---------------------------------------------------------------------------- +// Parser + +// TODO(gri) Imported objects don't have position information. +// Ideally use the debug table line info; alternatively +// create some fake position (or the position of the +// import). That way error messages referring to imported +// objects can print meaningful information. + +// parser parses the exports inside a gc compiler-produced +// object/archive file and populates its scope with the results. +type parser struct { + scanner scanner.Scanner + tok rune // current token + lit string // literal string; only valid for Ident, Int, String tokens + id string // package id of imported package + sharedPkgs map[string]*types.Package // package id -> package object (across importer) + localPkgs map[string]*types.Package // package id -> package object (just this package) +} + +func (p *parser) init(filename, id string, src io.Reader, packages map[string]*types.Package) { + p.scanner.Init(src) + p.scanner.Error = func(_ *scanner.Scanner, msg string) { p.error(msg) } + p.scanner.Mode = scanner.ScanIdents | scanner.ScanInts | scanner.ScanChars | scanner.ScanStrings | scanner.ScanComments | scanner.SkipComments + p.scanner.Whitespace = 1<<'\t' | 1<<' ' + p.scanner.Filename = filename // for good error messages + p.next() + p.id = id + p.sharedPkgs = packages + if debug { + // check consistency of packages map + for _, pkg := range packages { + if pkg.Name() == "" { + fmt.Printf("no package name for %s\n", pkg.Path()) + } + } + } +} + +func (p *parser) next() { + p.tok = p.scanner.Scan() + switch p.tok { + case scanner.Ident, scanner.Int, scanner.Char, scanner.String, '·': + p.lit = p.scanner.TokenText() + default: + p.lit = "" + } + if debug { + fmt.Printf("%s: %q -> %q\n", scanner.TokenString(p.tok), p.scanner.TokenText(), p.lit) + } +} + +func declTypeName(pkg *types.Package, name string) *types.TypeName { + scope := pkg.Scope() + if obj := scope.Lookup(name); obj != nil { + return obj.(*types.TypeName) + } + obj := types.NewTypeName(token.NoPos, pkg, name, nil) + // a named type may be referred to before the underlying type + // is known - set it up + types.NewNamed(obj, nil, nil) + scope.Insert(obj) + return obj +} + +// ---------------------------------------------------------------------------- +// Error handling + +// Internal errors are boxed as importErrors. +type importError struct { + pos scanner.Position + err error +} + +func (e importError) Error() string { + return fmt.Sprintf("import error %s (byte offset = %d): %s", e.pos, e.pos.Offset, e.err) +} + +func (p *parser) error(err interface{}) { + if s, ok := err.(string); ok { + err = errors.New(s) + } + // panic with a runtime.Error if err is not an error + panic(importError{p.scanner.Pos(), err.(error)}) +} + +func (p *parser) errorf(format string, args ...interface{}) { + p.error(fmt.Sprintf(format, args...)) +} + +func (p *parser) expect(tok rune) string { + lit := p.lit + if p.tok != tok { + p.errorf("expected %s, got %s (%s)", scanner.TokenString(tok), scanner.TokenString(p.tok), lit) + } + p.next() + return lit +} + +func (p *parser) expectSpecial(tok string) { + sep := 'x' // not white space + i := 0 + for i < len(tok) && p.tok == rune(tok[i]) && sep > ' ' { + sep = p.scanner.Peek() // if sep <= ' ', there is white space before the next token + p.next() + i++ + } + if i < len(tok) { + p.errorf("expected %q, got %q", tok, tok[0:i]) + } +} + +func (p *parser) expectKeyword(keyword string) { + lit := p.expect(scanner.Ident) + if lit != keyword { + p.errorf("expected keyword %s, got %q", keyword, lit) + } +} + +// ---------------------------------------------------------------------------- +// Qualified and unqualified names + +// PackageId = string_lit . +// +func (p *parser) parsePackageId() string { + id, err := strconv.Unquote(p.expect(scanner.String)) + if err != nil { + p.error(err) + } + // id == "" stands for the imported package id + // (only known at time of package installation) + if id == "" { + id = p.id + } + return id +} + +// PackageName = ident . +// +func (p *parser) parsePackageName() string { + return p.expect(scanner.Ident) +} + +// dotIdentifier = ( ident | '·' ) { ident | int | '·' } . +func (p *parser) parseDotIdent() string { + ident := "" + if p.tok != scanner.Int { + sep := 'x' // not white space + for (p.tok == scanner.Ident || p.tok == scanner.Int || p.tok == '·') && sep > ' ' { + ident += p.lit + sep = p.scanner.Peek() // if sep <= ' ', there is white space before the next token + p.next() + } + } + if ident == "" { + p.expect(scanner.Ident) // use expect() for error handling + } + return ident +} + +// QualifiedName = "@" PackageId "." ( "?" | dotIdentifier ) . +// +func (p *parser) parseQualifiedName() (id, name string) { + p.expect('@') + id = p.parsePackageId() + p.expect('.') + // Per rev f280b8a485fd (10/2/2013), qualified names may be used for anonymous fields. + if p.tok == '?' { + p.next() + } else { + name = p.parseDotIdent() + } + return +} + +// getPkg returns the package for a given id. If the package is +// not found, create the package and add it to the p.localPkgs +// and p.sharedPkgs maps. name is the (expected) name of the +// package. If name == "", the package name is expected to be +// set later via an import clause in the export data. +// +// id identifies a package, usually by a canonical package path like +// "encoding/json" but possibly by a non-canonical import path like +// "./json". +// +func (p *parser) getPkg(id, name string) *types.Package { + // package unsafe is not in the packages maps - handle explicitly + if id == "unsafe" { + return types.Unsafe + } + + pkg := p.localPkgs[id] + if pkg == nil { + // first import of id from this package + pkg = p.sharedPkgs[id] + if pkg == nil { + // first import of id by this importer; + // add (possibly unnamed) pkg to shared packages + pkg = types.NewPackage(id, name) + p.sharedPkgs[id] = pkg + } + // add (possibly unnamed) pkg to local packages + if p.localPkgs == nil { + p.localPkgs = make(map[string]*types.Package) + } + p.localPkgs[id] = pkg + } else if name != "" { + // package exists already and we have an expected package name; + // make sure names match or set package name if necessary + if pname := pkg.Name(); pname == "" { + pkg.SetName(name) + } else if pname != name { + p.errorf("%s package name mismatch: %s (given) vs %s (expected)", id, pname, name) + } + } + return pkg +} + +// parseExportedName is like parseQualifiedName, but +// the package id is resolved to an imported *types.Package. +// +func (p *parser) parseExportedName() (pkg *types.Package, name string) { + id, name := p.parseQualifiedName() + pkg = p.getPkg(id, "") + return +} + +// ---------------------------------------------------------------------------- +// Types + +// BasicType = identifier . +// +func (p *parser) parseBasicType() types.Type { + id := p.expect(scanner.Ident) + obj := types.Universe.Lookup(id) + if obj, ok := obj.(*types.TypeName); ok { + return obj.Type() + } + p.errorf("not a basic type: %s", id) + return nil +} + +// ArrayType = "[" int_lit "]" Type . +// +func (p *parser) parseArrayType(parent *types.Package) types.Type { + // "[" already consumed and lookahead known not to be "]" + lit := p.expect(scanner.Int) + p.expect(']') + elem := p.parseType(parent) + n, err := strconv.ParseInt(lit, 10, 64) + if err != nil { + p.error(err) + } + return types.NewArray(elem, n) +} + +// MapType = "map" "[" Type "]" Type . +// +func (p *parser) parseMapType(parent *types.Package) types.Type { + p.expectKeyword("map") + p.expect('[') + key := p.parseType(parent) + p.expect(']') + elem := p.parseType(parent) + return types.NewMap(key, elem) +} + +// Name = identifier | "?" | QualifiedName . +// +// For unqualified and anonymous names, the returned package is the parent +// package unless parent == nil, in which case the returned package is the +// package being imported. (The parent package is not nil if the the name +// is an unqualified struct field or interface method name belonging to a +// type declared in another package.) +// +// For qualified names, the returned package is nil (and not created if +// it doesn't exist yet) unless materializePkg is set (which creates an +// unnamed package with valid package path). In the latter case, a +// subsequent import clause is expected to provide a name for the package. +// +func (p *parser) parseName(parent *types.Package, materializePkg bool) (pkg *types.Package, name string) { + pkg = parent + if pkg == nil { + pkg = p.sharedPkgs[p.id] + } + switch p.tok { + case scanner.Ident: + name = p.lit + p.next() + case '?': + // anonymous + p.next() + case '@': + // exported name prefixed with package path + pkg = nil + var id string + id, name = p.parseQualifiedName() + if materializePkg { + pkg = p.getPkg(id, "") + } + default: + p.error("name expected") + } + return +} + +func deref(typ types.Type) types.Type { + if p, _ := typ.(*types.Pointer); p != nil { + return p.Elem() + } + return typ +} + +// Field = Name Type [ string_lit ] . +// +func (p *parser) parseField(parent *types.Package) (*types.Var, string) { + pkg, name := p.parseName(parent, true) + + if name == "_" { + // Blank fields should be package-qualified because they + // are unexported identifiers, but gc does not qualify them. + // Assuming that the ident belongs to the current package + // causes types to change during re-exporting, leading + // to spurious "can't assign A to B" errors from go/types. + // As a workaround, pretend all blank fields belong + // to the same unique dummy package. + const blankpkg = "<_>" + pkg = p.getPkg(blankpkg, blankpkg) + } + + typ := p.parseType(parent) + anonymous := false + if name == "" { + // anonymous field - typ must be T or *T and T must be a type name + switch typ := deref(typ).(type) { + case *types.Basic: // basic types are named types + pkg = nil // objects defined in Universe scope have no package + name = typ.Name() + case *types.Named: + name = typ.Obj().Name() + default: + p.errorf("anonymous field expected") + } + anonymous = true + } + tag := "" + if p.tok == scanner.String { + s := p.expect(scanner.String) + var err error + tag, err = strconv.Unquote(s) + if err != nil { + p.errorf("invalid struct tag %s: %s", s, err) + } + } + return types.NewField(token.NoPos, pkg, name, typ, anonymous), tag +} + +// StructType = "struct" "{" [ FieldList ] "}" . +// FieldList = Field { ";" Field } . +// +func (p *parser) parseStructType(parent *types.Package) types.Type { + var fields []*types.Var + var tags []string + + p.expectKeyword("struct") + p.expect('{') + for i := 0; p.tok != '}' && p.tok != scanner.EOF; i++ { + if i > 0 { + p.expect(';') + } + fld, tag := p.parseField(parent) + if tag != "" && tags == nil { + tags = make([]string, i) + } + if tags != nil { + tags = append(tags, tag) + } + fields = append(fields, fld) + } + p.expect('}') + + return types.NewStruct(fields, tags) +} + +// Parameter = ( identifier | "?" ) [ "..." ] Type [ string_lit ] . +// +func (p *parser) parseParameter() (par *types.Var, isVariadic bool) { + _, name := p.parseName(nil, false) + // remove gc-specific parameter numbering + if i := strings.Index(name, "·"); i >= 0 { + name = name[:i] + } + if p.tok == '.' { + p.expectSpecial("...") + isVariadic = true + } + typ := p.parseType(nil) + if isVariadic { + typ = types.NewSlice(typ) + } + // ignore argument tag (e.g. "noescape") + if p.tok == scanner.String { + p.next() + } + // TODO(gri) should we provide a package? + par = types.NewVar(token.NoPos, nil, name, typ) + return +} + +// Parameters = "(" [ ParameterList ] ")" . +// ParameterList = { Parameter "," } Parameter . +// +func (p *parser) parseParameters() (list []*types.Var, isVariadic bool) { + p.expect('(') + for p.tok != ')' && p.tok != scanner.EOF { + if len(list) > 0 { + p.expect(',') + } + par, variadic := p.parseParameter() + list = append(list, par) + if variadic { + if isVariadic { + p.error("... not on final argument") + } + isVariadic = true + } + } + p.expect(')') + + return +} + +// Signature = Parameters [ Result ] . +// Result = Type | Parameters . +// +func (p *parser) parseSignature(recv *types.Var) *types.Signature { + params, isVariadic := p.parseParameters() + + // optional result type + var results []*types.Var + if p.tok == '(' { + var variadic bool + results, variadic = p.parseParameters() + if variadic { + p.error("... not permitted on result type") + } + } + + return types.NewSignature(recv, types.NewTuple(params...), types.NewTuple(results...), isVariadic) +} + +// InterfaceType = "interface" "{" [ MethodList ] "}" . +// MethodList = Method { ";" Method } . +// Method = Name Signature . +// +// The methods of embedded interfaces are always "inlined" +// by the compiler and thus embedded interfaces are never +// visible in the export data. +// +func (p *parser) parseInterfaceType(parent *types.Package) types.Type { + var methods []*types.Func + + p.expectKeyword("interface") + p.expect('{') + for i := 0; p.tok != '}' && p.tok != scanner.EOF; i++ { + if i > 0 { + p.expect(';') + } + pkg, name := p.parseName(parent, true) + sig := p.parseSignature(nil) + methods = append(methods, types.NewFunc(token.NoPos, pkg, name, sig)) + } + p.expect('}') + + // Complete requires the type's embedded interfaces to be fully defined, + // but we do not define any + return types.NewInterface(methods, nil).Complete() +} + +// ChanType = ( "chan" [ "<-" ] | "<-" "chan" ) Type . +// +func (p *parser) parseChanType(parent *types.Package) types.Type { + dir := types.SendRecv + if p.tok == scanner.Ident { + p.expectKeyword("chan") + if p.tok == '<' { + p.expectSpecial("<-") + dir = types.SendOnly + } + } else { + p.expectSpecial("<-") + p.expectKeyword("chan") + dir = types.RecvOnly + } + elem := p.parseType(parent) + return types.NewChan(dir, elem) +} + +// Type = +// BasicType | TypeName | ArrayType | SliceType | StructType | +// PointerType | FuncType | InterfaceType | MapType | ChanType | +// "(" Type ")" . +// +// BasicType = ident . +// TypeName = ExportedName . +// SliceType = "[" "]" Type . +// PointerType = "*" Type . +// FuncType = "func" Signature . +// +func (p *parser) parseType(parent *types.Package) types.Type { + switch p.tok { + case scanner.Ident: + switch p.lit { + default: + return p.parseBasicType() + case "struct": + return p.parseStructType(parent) + case "func": + // FuncType + p.next() + return p.parseSignature(nil) + case "interface": + return p.parseInterfaceType(parent) + case "map": + return p.parseMapType(parent) + case "chan": + return p.parseChanType(parent) + } + case '@': + // TypeName + pkg, name := p.parseExportedName() + return declTypeName(pkg, name).Type() + case '[': + p.next() // look ahead + if p.tok == ']' { + // SliceType + p.next() + return types.NewSlice(p.parseType(parent)) + } + return p.parseArrayType(parent) + case '*': + // PointerType + p.next() + return types.NewPointer(p.parseType(parent)) + case '<': + return p.parseChanType(parent) + case '(': + // "(" Type ")" + p.next() + typ := p.parseType(parent) + p.expect(')') + return typ + } + p.errorf("expected type, got %s (%q)", scanner.TokenString(p.tok), p.lit) + return nil +} + +// ---------------------------------------------------------------------------- +// Declarations + +// ImportDecl = "import" PackageName PackageId . +// +func (p *parser) parseImportDecl() { + p.expectKeyword("import") + name := p.parsePackageName() + p.getPkg(p.parsePackageId(), name) +} + +// int_lit = [ "+" | "-" ] { "0" ... "9" } . +// +func (p *parser) parseInt() string { + s := "" + switch p.tok { + case '-': + s = "-" + p.next() + case '+': + p.next() + } + return s + p.expect(scanner.Int) +} + +// number = int_lit [ "p" int_lit ] . +// +func (p *parser) parseNumber() (typ *types.Basic, val constant.Value) { + // mantissa + mant := constant.MakeFromLiteral(p.parseInt(), token.INT, 0) + if mant == nil { + panic("invalid mantissa") + } + + if p.lit == "p" { + // exponent (base 2) + p.next() + exp, err := strconv.ParseInt(p.parseInt(), 10, 0) + if err != nil { + p.error(err) + } + if exp < 0 { + denom := constant.MakeInt64(1) + denom = constant.Shift(denom, token.SHL, uint(-exp)) + typ = types.Typ[types.UntypedFloat] + val = constant.BinaryOp(mant, token.QUO, denom) + return + } + if exp > 0 { + mant = constant.Shift(mant, token.SHL, uint(exp)) + } + typ = types.Typ[types.UntypedFloat] + val = mant + return + } + + typ = types.Typ[types.UntypedInt] + val = mant + return +} + +// ConstDecl = "const" ExportedName [ Type ] "=" Literal . +// Literal = bool_lit | int_lit | float_lit | complex_lit | rune_lit | string_lit . +// bool_lit = "true" | "false" . +// complex_lit = "(" float_lit "+" float_lit "i" ")" . +// rune_lit = "(" int_lit "+" int_lit ")" . +// string_lit = `"` { unicode_char } `"` . +// +func (p *parser) parseConstDecl() { + p.expectKeyword("const") + pkg, name := p.parseExportedName() + + var typ0 types.Type + if p.tok != '=' { + // constant types are never structured - no need for parent type + typ0 = p.parseType(nil) + } + + p.expect('=') + var typ types.Type + var val constant.Value + switch p.tok { + case scanner.Ident: + // bool_lit + if p.lit != "true" && p.lit != "false" { + p.error("expected true or false") + } + typ = types.Typ[types.UntypedBool] + val = constant.MakeBool(p.lit == "true") + p.next() + + case '-', scanner.Int: + // int_lit + typ, val = p.parseNumber() + + case '(': + // complex_lit or rune_lit + p.next() + if p.tok == scanner.Char { + p.next() + p.expect('+') + typ = types.Typ[types.UntypedRune] + _, val = p.parseNumber() + p.expect(')') + break + } + _, re := p.parseNumber() + p.expect('+') + _, im := p.parseNumber() + p.expectKeyword("i") + p.expect(')') + typ = types.Typ[types.UntypedComplex] + val = constant.BinaryOp(re, token.ADD, constant.MakeImag(im)) + + case scanner.Char: + // rune_lit + typ = types.Typ[types.UntypedRune] + val = constant.MakeFromLiteral(p.lit, token.CHAR, 0) + p.next() + + case scanner.String: + // string_lit + typ = types.Typ[types.UntypedString] + val = constant.MakeFromLiteral(p.lit, token.STRING, 0) + p.next() + + default: + p.errorf("expected literal got %s", scanner.TokenString(p.tok)) + } + + if typ0 == nil { + typ0 = typ + } + + pkg.Scope().Insert(types.NewConst(token.NoPos, pkg, name, typ0, val)) +} + +// TypeDecl = "type" ExportedName Type . +// +func (p *parser) parseTypeDecl() { + p.expectKeyword("type") + pkg, name := p.parseExportedName() + obj := declTypeName(pkg, name) + + // The type object may have been imported before and thus already + // have a type associated with it. We still need to parse the type + // structure, but throw it away if the object already has a type. + // This ensures that all imports refer to the same type object for + // a given type declaration. + typ := p.parseType(pkg) + + if name := obj.Type().(*types.Named); name.Underlying() == nil { + name.SetUnderlying(typ) + } +} + +// VarDecl = "var" ExportedName Type . +// +func (p *parser) parseVarDecl() { + p.expectKeyword("var") + pkg, name := p.parseExportedName() + typ := p.parseType(pkg) + pkg.Scope().Insert(types.NewVar(token.NoPos, pkg, name, typ)) +} + +// Func = Signature [ Body ] . +// Body = "{" ... "}" . +// +func (p *parser) parseFunc(recv *types.Var) *types.Signature { + sig := p.parseSignature(recv) + if p.tok == '{' { + p.next() + for i := 1; i > 0; p.next() { + switch p.tok { + case '{': + i++ + case '}': + i-- + } + } + } + return sig +} + +// MethodDecl = "func" Receiver Name Func . +// Receiver = "(" ( identifier | "?" ) [ "*" ] ExportedName ")" . +// +func (p *parser) parseMethodDecl() { + // "func" already consumed + p.expect('(') + recv, _ := p.parseParameter() // receiver + p.expect(')') + + // determine receiver base type object + base := deref(recv.Type()).(*types.Named) + + // parse method name, signature, and possibly inlined body + _, name := p.parseName(nil, false) + sig := p.parseFunc(recv) + + // methods always belong to the same package as the base type object + pkg := base.Obj().Pkg() + + // add method to type unless type was imported before + // and method exists already + // TODO(gri) This leads to a quadratic algorithm - ok for now because method counts are small. + base.AddMethod(types.NewFunc(token.NoPos, pkg, name, sig)) +} + +// FuncDecl = "func" ExportedName Func . +// +func (p *parser) parseFuncDecl() { + // "func" already consumed + pkg, name := p.parseExportedName() + typ := p.parseFunc(nil) + pkg.Scope().Insert(types.NewFunc(token.NoPos, pkg, name, typ)) +} + +// Decl = [ ImportDecl | ConstDecl | TypeDecl | VarDecl | FuncDecl | MethodDecl ] "\n" . +// +func (p *parser) parseDecl() { + if p.tok == scanner.Ident { + switch p.lit { + case "import": + p.parseImportDecl() + case "const": + p.parseConstDecl() + case "type": + p.parseTypeDecl() + case "var": + p.parseVarDecl() + case "func": + p.next() // look ahead + if p.tok == '(' { + p.parseMethodDecl() + } else { + p.parseFuncDecl() + } + } + } + p.expect('\n') +} + +// ---------------------------------------------------------------------------- +// Export + +// Export = "PackageClause { Decl } "$$" . +// PackageClause = "package" PackageName [ "safe" ] "\n" . +// +func (p *parser) parseExport() *types.Package { + p.expectKeyword("package") + name := p.parsePackageName() + if p.tok == scanner.Ident && p.lit == "safe" { + // package was compiled with -u option - ignore + p.next() + } + p.expect('\n') + + pkg := p.getPkg(p.id, name) + + for p.tok != '$' && p.tok != scanner.EOF { + p.parseDecl() + } + + if ch := p.scanner.Peek(); p.tok != '$' || ch != '$' { + // don't call next()/expect() since reading past the + // export data may cause scanner errors (e.g. NUL chars) + p.errorf("expected '$$', got %s %c", scanner.TokenString(p.tok), ch) + } + + if n := p.scanner.ErrorCount; n != 0 { + p.errorf("expected no scanner errors, got %d", n) + } + + // Record all locally referenced packages as imports. + var imports []*types.Package + for id, pkg2 := range p.localPkgs { + if pkg2.Name() == "" { + p.errorf("%s package has no name", id) + } + if id == p.id { + continue // avoid self-edge + } + imports = append(imports, pkg2) + } + sort.Sort(byPath(imports)) + pkg.SetImports(imports) + + // package was imported completely and without errors + pkg.MarkComplete() + + return pkg +} + +type byPath []*types.Package + +func (a byPath) Len() int { return len(a) } +func (a byPath) Swap(i, j int) { a[i], a[j] = a[j], a[i] } +func (a byPath) Less(i, j int) bool { return a[i].Path() < a[j].Path() } diff --git a/vendor/golang.org/x/tools/go/internal/gcimporter/iimport.go b/vendor/golang.org/x/tools/go/internal/gcimporter/iimport.go new file mode 100644 index 0000000000..0fd22bb038 --- /dev/null +++ b/vendor/golang.org/x/tools/go/internal/gcimporter/iimport.go @@ -0,0 +1,598 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Indexed package import. +// See cmd/compile/internal/gc/iexport.go for the export data format. + +// This file is a copy of $GOROOT/src/go/internal/gcimporter/iimport.go. + +package gcimporter + +import ( + "bytes" + "encoding/binary" + "fmt" + "go/constant" + "go/token" + "go/types" + "io" + "sort" +) + +type intReader struct { + *bytes.Reader + path string +} + +func (r *intReader) int64() int64 { + i, err := binary.ReadVarint(r.Reader) + if err != nil { + errorf("import %q: read varint error: %v", r.path, err) + } + return i +} + +func (r *intReader) uint64() uint64 { + i, err := binary.ReadUvarint(r.Reader) + if err != nil { + errorf("import %q: read varint error: %v", r.path, err) + } + return i +} + +const predeclReserved = 32 + +type itag uint64 + +const ( + // Types + definedType itag = iota + pointerType + sliceType + arrayType + chanType + mapType + signatureType + structType + interfaceType +) + +// IImportData imports a package from the serialized package data +// and returns the number of bytes consumed and a reference to the package. +// If the export data version is not recognized or the format is otherwise +// compromised, an error is returned. +func IImportData(fset *token.FileSet, imports map[string]*types.Package, data []byte, path string) (_ int, pkg *types.Package, err error) { + const currentVersion = 0 + version := -1 + defer func() { + if e := recover(); e != nil { + if version > currentVersion { + err = fmt.Errorf("cannot import %q (%v), export data is newer version - update tool", path, e) + } else { + err = fmt.Errorf("cannot import %q (%v), possibly version skew - reinstall package", path, e) + } + } + }() + + r := &intReader{bytes.NewReader(data), path} + + version = int(r.uint64()) + switch version { + case currentVersion: + default: + errorf("unknown iexport format version %d", version) + } + + sLen := int64(r.uint64()) + dLen := int64(r.uint64()) + + whence, _ := r.Seek(0, io.SeekCurrent) + stringData := data[whence : whence+sLen] + declData := data[whence+sLen : whence+sLen+dLen] + r.Seek(sLen+dLen, io.SeekCurrent) + + p := iimporter{ + ipath: path, + + stringData: stringData, + stringCache: make(map[uint64]string), + pkgCache: make(map[uint64]*types.Package), + + declData: declData, + pkgIndex: make(map[*types.Package]map[string]uint64), + typCache: make(map[uint64]types.Type), + + fake: fakeFileSet{ + fset: fset, + files: make(map[string]*token.File), + }, + } + + for i, pt := range predeclared { + p.typCache[uint64(i)] = pt + } + + pkgList := make([]*types.Package, r.uint64()) + for i := range pkgList { + pkgPathOff := r.uint64() + pkgPath := p.stringAt(pkgPathOff) + pkgName := p.stringAt(r.uint64()) + _ = r.uint64() // package height; unused by go/types + + if pkgPath == "" { + pkgPath = path + } + pkg := imports[pkgPath] + if pkg == nil { + pkg = types.NewPackage(pkgPath, pkgName) + imports[pkgPath] = pkg + } else if pkg.Name() != pkgName { + errorf("conflicting names %s and %s for package %q", pkg.Name(), pkgName, path) + } + + p.pkgCache[pkgPathOff] = pkg + + nameIndex := make(map[string]uint64) + for nSyms := r.uint64(); nSyms > 0; nSyms-- { + name := p.stringAt(r.uint64()) + nameIndex[name] = r.uint64() + } + + p.pkgIndex[pkg] = nameIndex + pkgList[i] = pkg + } + + localpkg := pkgList[0] + + names := make([]string, 0, len(p.pkgIndex[localpkg])) + for name := range p.pkgIndex[localpkg] { + names = append(names, name) + } + sort.Strings(names) + for _, name := range names { + p.doDecl(localpkg, name) + } + + for _, typ := range p.interfaceList { + typ.Complete() + } + + // record all referenced packages as imports + list := append(([]*types.Package)(nil), pkgList[1:]...) + sort.Sort(byPath(list)) + localpkg.SetImports(list) + + // package was imported completely and without errors + localpkg.MarkComplete() + + consumed, _ := r.Seek(0, io.SeekCurrent) + return int(consumed), localpkg, nil +} + +type iimporter struct { + ipath string + + stringData []byte + stringCache map[uint64]string + pkgCache map[uint64]*types.Package + + declData []byte + pkgIndex map[*types.Package]map[string]uint64 + typCache map[uint64]types.Type + + fake fakeFileSet + interfaceList []*types.Interface +} + +func (p *iimporter) doDecl(pkg *types.Package, name string) { + // See if we've already imported this declaration. + if obj := pkg.Scope().Lookup(name); obj != nil { + return + } + + off, ok := p.pkgIndex[pkg][name] + if !ok { + errorf("%v.%v not in index", pkg, name) + } + + r := &importReader{p: p, currPkg: pkg} + r.declReader.Reset(p.declData[off:]) + + r.obj(name) +} + +func (p *iimporter) stringAt(off uint64) string { + if s, ok := p.stringCache[off]; ok { + return s + } + + slen, n := binary.Uvarint(p.stringData[off:]) + if n <= 0 { + errorf("varint failed") + } + spos := off + uint64(n) + s := string(p.stringData[spos : spos+slen]) + p.stringCache[off] = s + return s +} + +func (p *iimporter) pkgAt(off uint64) *types.Package { + if pkg, ok := p.pkgCache[off]; ok { + return pkg + } + path := p.stringAt(off) + errorf("missing package %q in %q", path, p.ipath) + return nil +} + +func (p *iimporter) typAt(off uint64, base *types.Named) types.Type { + if t, ok := p.typCache[off]; ok && (base == nil || !isInterface(t)) { + return t + } + + if off < predeclReserved { + errorf("predeclared type missing from cache: %v", off) + } + + r := &importReader{p: p} + r.declReader.Reset(p.declData[off-predeclReserved:]) + t := r.doType(base) + + if base == nil || !isInterface(t) { + p.typCache[off] = t + } + return t +} + +type importReader struct { + p *iimporter + declReader bytes.Reader + currPkg *types.Package + prevFile string + prevLine int64 +} + +func (r *importReader) obj(name string) { + tag := r.byte() + pos := r.pos() + + switch tag { + case 'A': + typ := r.typ() + + r.declare(types.NewTypeName(pos, r.currPkg, name, typ)) + + case 'C': + typ, val := r.value() + + r.declare(types.NewConst(pos, r.currPkg, name, typ, val)) + + case 'F': + sig := r.signature(nil) + + r.declare(types.NewFunc(pos, r.currPkg, name, sig)) + + case 'T': + // Types can be recursive. We need to setup a stub + // declaration before recursing. + obj := types.NewTypeName(pos, r.currPkg, name, nil) + named := types.NewNamed(obj, nil, nil) + r.declare(obj) + + underlying := r.p.typAt(r.uint64(), named).Underlying() + named.SetUnderlying(underlying) + + if !isInterface(underlying) { + for n := r.uint64(); n > 0; n-- { + mpos := r.pos() + mname := r.ident() + recv := r.param() + msig := r.signature(recv) + + named.AddMethod(types.NewFunc(mpos, r.currPkg, mname, msig)) + } + } + + case 'V': + typ := r.typ() + + r.declare(types.NewVar(pos, r.currPkg, name, typ)) + + default: + errorf("unexpected tag: %v", tag) + } +} + +func (r *importReader) declare(obj types.Object) { + obj.Pkg().Scope().Insert(obj) +} + +func (r *importReader) value() (typ types.Type, val constant.Value) { + typ = r.typ() + + switch b := typ.Underlying().(*types.Basic); b.Info() & types.IsConstType { + case types.IsBoolean: + val = constant.MakeBool(r.bool()) + + case types.IsString: + val = constant.MakeString(r.string()) + + case types.IsInteger: + val = r.mpint(b) + + case types.IsFloat: + val = r.mpfloat(b) + + case types.IsComplex: + re := r.mpfloat(b) + im := r.mpfloat(b) + val = constant.BinaryOp(re, token.ADD, constant.MakeImag(im)) + + default: + errorf("unexpected type %v", typ) // panics + panic("unreachable") + } + + return +} + +func intSize(b *types.Basic) (signed bool, maxBytes uint) { + if (b.Info() & types.IsUntyped) != 0 { + return true, 64 + } + + switch b.Kind() { + case types.Float32, types.Complex64: + return true, 3 + case types.Float64, types.Complex128: + return true, 7 + } + + signed = (b.Info() & types.IsUnsigned) == 0 + switch b.Kind() { + case types.Int8, types.Uint8: + maxBytes = 1 + case types.Int16, types.Uint16: + maxBytes = 2 + case types.Int32, types.Uint32: + maxBytes = 4 + default: + maxBytes = 8 + } + + return +} + +func (r *importReader) mpint(b *types.Basic) constant.Value { + signed, maxBytes := intSize(b) + + maxSmall := 256 - maxBytes + if signed { + maxSmall = 256 - 2*maxBytes + } + if maxBytes == 1 { + maxSmall = 256 + } + + n, _ := r.declReader.ReadByte() + if uint(n) < maxSmall { + v := int64(n) + if signed { + v >>= 1 + if n&1 != 0 { + v = ^v + } + } + return constant.MakeInt64(v) + } + + v := -n + if signed { + v = -(n &^ 1) >> 1 + } + if v < 1 || uint(v) > maxBytes { + errorf("weird decoding: %v, %v => %v", n, signed, v) + } + + buf := make([]byte, v) + io.ReadFull(&r.declReader, buf) + + // convert to little endian + // TODO(gri) go/constant should have a more direct conversion function + // (e.g., once it supports a big.Float based implementation) + for i, j := 0, len(buf)-1; i < j; i, j = i+1, j-1 { + buf[i], buf[j] = buf[j], buf[i] + } + + x := constant.MakeFromBytes(buf) + if signed && n&1 != 0 { + x = constant.UnaryOp(token.SUB, x, 0) + } + return x +} + +func (r *importReader) mpfloat(b *types.Basic) constant.Value { + x := r.mpint(b) + if constant.Sign(x) == 0 { + return x + } + + exp := r.int64() + switch { + case exp > 0: + x = constant.Shift(x, token.SHL, uint(exp)) + case exp < 0: + d := constant.Shift(constant.MakeInt64(1), token.SHL, uint(-exp)) + x = constant.BinaryOp(x, token.QUO, d) + } + return x +} + +func (r *importReader) ident() string { + return r.string() +} + +func (r *importReader) qualifiedIdent() (*types.Package, string) { + name := r.string() + pkg := r.pkg() + return pkg, name +} + +func (r *importReader) pos() token.Pos { + delta := r.int64() + if delta != deltaNewFile { + r.prevLine += delta + } else if l := r.int64(); l == -1 { + r.prevLine += deltaNewFile + } else { + r.prevFile = r.string() + r.prevLine = l + } + + if r.prevFile == "" && r.prevLine == 0 { + return token.NoPos + } + + return r.p.fake.pos(r.prevFile, int(r.prevLine)) +} + +func (r *importReader) typ() types.Type { + return r.p.typAt(r.uint64(), nil) +} + +func isInterface(t types.Type) bool { + _, ok := t.(*types.Interface) + return ok +} + +func (r *importReader) pkg() *types.Package { return r.p.pkgAt(r.uint64()) } +func (r *importReader) string() string { return r.p.stringAt(r.uint64()) } + +func (r *importReader) doType(base *types.Named) types.Type { + switch k := r.kind(); k { + default: + errorf("unexpected kind tag in %q: %v", r.p.ipath, k) + return nil + + case definedType: + pkg, name := r.qualifiedIdent() + r.p.doDecl(pkg, name) + return pkg.Scope().Lookup(name).(*types.TypeName).Type() + case pointerType: + return types.NewPointer(r.typ()) + case sliceType: + return types.NewSlice(r.typ()) + case arrayType: + n := r.uint64() + return types.NewArray(r.typ(), int64(n)) + case chanType: + dir := chanDir(int(r.uint64())) + return types.NewChan(dir, r.typ()) + case mapType: + return types.NewMap(r.typ(), r.typ()) + case signatureType: + r.currPkg = r.pkg() + return r.signature(nil) + + case structType: + r.currPkg = r.pkg() + + fields := make([]*types.Var, r.uint64()) + tags := make([]string, len(fields)) + for i := range fields { + fpos := r.pos() + fname := r.ident() + ftyp := r.typ() + emb := r.bool() + tag := r.string() + + fields[i] = types.NewField(fpos, r.currPkg, fname, ftyp, emb) + tags[i] = tag + } + return types.NewStruct(fields, tags) + + case interfaceType: + r.currPkg = r.pkg() + + embeddeds := make([]types.Type, r.uint64()) + for i := range embeddeds { + _ = r.pos() + embeddeds[i] = r.typ() + } + + methods := make([]*types.Func, r.uint64()) + for i := range methods { + mpos := r.pos() + mname := r.ident() + + // TODO(mdempsky): Matches bimport.go, but I + // don't agree with this. + var recv *types.Var + if base != nil { + recv = types.NewVar(token.NoPos, r.currPkg, "", base) + } + + msig := r.signature(recv) + methods[i] = types.NewFunc(mpos, r.currPkg, mname, msig) + } + + typ := newInterface(methods, embeddeds) + r.p.interfaceList = append(r.p.interfaceList, typ) + return typ + } +} + +func (r *importReader) kind() itag { + return itag(r.uint64()) +} + +func (r *importReader) signature(recv *types.Var) *types.Signature { + params := r.paramList() + results := r.paramList() + variadic := params.Len() > 0 && r.bool() + return types.NewSignature(recv, params, results, variadic) +} + +func (r *importReader) paramList() *types.Tuple { + xs := make([]*types.Var, r.uint64()) + for i := range xs { + xs[i] = r.param() + } + return types.NewTuple(xs...) +} + +func (r *importReader) param() *types.Var { + pos := r.pos() + name := r.ident() + typ := r.typ() + return types.NewParam(pos, r.currPkg, name, typ) +} + +func (r *importReader) bool() bool { + return r.uint64() != 0 +} + +func (r *importReader) int64() int64 { + n, err := binary.ReadVarint(&r.declReader) + if err != nil { + errorf("readVarint: %v", err) + } + return n +} + +func (r *importReader) uint64() uint64 { + n, err := binary.ReadUvarint(&r.declReader) + if err != nil { + errorf("readUvarint: %v", err) + } + return n +} + +func (r *importReader) byte() byte { + x, err := r.declReader.ReadByte() + if err != nil { + errorf("declReader.ReadByte: %v", err) + } + return x +} diff --git a/vendor/golang.org/x/tools/go/internal/gcimporter/newInterface10.go b/vendor/golang.org/x/tools/go/internal/gcimporter/newInterface10.go new file mode 100644 index 0000000000..463f252271 --- /dev/null +++ b/vendor/golang.org/x/tools/go/internal/gcimporter/newInterface10.go @@ -0,0 +1,21 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build !go1.11 + +package gcimporter + +import "go/types" + +func newInterface(methods []*types.Func, embeddeds []types.Type) *types.Interface { + named := make([]*types.Named, len(embeddeds)) + for i, e := range embeddeds { + var ok bool + named[i], ok = e.(*types.Named) + if !ok { + panic("embedding of non-defined interfaces in interfaces is not supported before Go 1.11") + } + } + return types.NewInterface(methods, named) +} diff --git a/vendor/golang.org/x/tools/go/internal/gcimporter/newInterface11.go b/vendor/golang.org/x/tools/go/internal/gcimporter/newInterface11.go new file mode 100644 index 0000000000..ab28b95cbb --- /dev/null +++ b/vendor/golang.org/x/tools/go/internal/gcimporter/newInterface11.go @@ -0,0 +1,13 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build go1.11 + +package gcimporter + +import "go/types" + +func newInterface(methods []*types.Func, embeddeds []types.Type) *types.Interface { + return types.NewInterfaceType(methods, embeddeds) +} diff --git a/vendor/golang.org/x/tools/go/loader/doc.go b/vendor/golang.org/x/tools/go/loader/doc.go new file mode 100644 index 0000000000..9b51c9ecde --- /dev/null +++ b/vendor/golang.org/x/tools/go/loader/doc.go @@ -0,0 +1,205 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package loader loads a complete Go program from source code, parsing +// and type-checking the initial packages plus their transitive closure +// of dependencies. The ASTs and the derived facts are retained for +// later use. +// +// THIS INTERFACE IS EXPERIMENTAL AND IS LIKELY TO CHANGE. +// +// The package defines two primary types: Config, which specifies a +// set of initial packages to load and various other options; and +// Program, which is the result of successfully loading the packages +// specified by a configuration. +// +// The configuration can be set directly, but *Config provides various +// convenience methods to simplify the common cases, each of which can +// be called any number of times. Finally, these are followed by a +// call to Load() to actually load and type-check the program. +// +// var conf loader.Config +// +// // Use the command-line arguments to specify +// // a set of initial packages to load from source. +// // See FromArgsUsage for help. +// rest, err := conf.FromArgs(os.Args[1:], wantTests) +// +// // Parse the specified files and create an ad hoc package with path "foo". +// // All files must have the same 'package' declaration. +// conf.CreateFromFilenames("foo", "foo.go", "bar.go") +// +// // Create an ad hoc package with path "foo" from +// // the specified already-parsed files. +// // All ASTs must have the same 'package' declaration. +// conf.CreateFromFiles("foo", parsedFiles) +// +// // Add "runtime" to the set of packages to be loaded. +// conf.Import("runtime") +// +// // Adds "fmt" and "fmt_test" to the set of packages +// // to be loaded. "fmt" will include *_test.go files. +// conf.ImportWithTests("fmt") +// +// // Finally, load all the packages specified by the configuration. +// prog, err := conf.Load() +// +// See examples_test.go for examples of API usage. +// +// +// CONCEPTS AND TERMINOLOGY +// +// The WORKSPACE is the set of packages accessible to the loader. The +// workspace is defined by Config.Build, a *build.Context. The +// default context treats subdirectories of $GOROOT and $GOPATH as +// packages, but this behavior may be overridden. +// +// An AD HOC package is one specified as a set of source files on the +// command line. In the simplest case, it may consist of a single file +// such as $GOROOT/src/net/http/triv.go. +// +// EXTERNAL TEST packages are those comprised of a set of *_test.go +// files all with the same 'package foo_test' declaration, all in the +// same directory. (go/build.Package calls these files XTestFiles.) +// +// An IMPORTABLE package is one that can be referred to by some import +// spec. Every importable package is uniquely identified by its +// PACKAGE PATH or just PATH, a string such as "fmt", "encoding/json", +// or "cmd/vendor/golang.org/x/arch/x86/x86asm". A package path +// typically denotes a subdirectory of the workspace. +// +// An import declaration uses an IMPORT PATH to refer to a package. +// Most import declarations use the package path as the import path. +// +// Due to VENDORING (https://golang.org/s/go15vendor), the +// interpretation of an import path may depend on the directory in which +// it appears. To resolve an import path to a package path, go/build +// must search the enclosing directories for a subdirectory named +// "vendor". +// +// ad hoc packages and external test packages are NON-IMPORTABLE. The +// path of an ad hoc package is inferred from the package +// declarations of its files and is therefore not a unique package key. +// For example, Config.CreatePkgs may specify two initial ad hoc +// packages, both with path "main". +// +// An AUGMENTED package is an importable package P plus all the +// *_test.go files with same 'package foo' declaration as P. +// (go/build.Package calls these files TestFiles.) +// +// The INITIAL packages are those specified in the configuration. A +// DEPENDENCY is a package loaded to satisfy an import in an initial +// package or another dependency. +// +package loader + +// IMPLEMENTATION NOTES +// +// 'go test', in-package test files, and import cycles +// --------------------------------------------------- +// +// An external test package may depend upon members of the augmented +// package that are not in the unaugmented package, such as functions +// that expose internals. (See bufio/export_test.go for an example.) +// So, the loader must ensure that for each external test package +// it loads, it also augments the corresponding non-test package. +// +// The import graph over n unaugmented packages must be acyclic; the +// import graph over n-1 unaugmented packages plus one augmented +// package must also be acyclic. ('go test' relies on this.) But the +// import graph over n augmented packages may contain cycles. +// +// First, all the (unaugmented) non-test packages and their +// dependencies are imported in the usual way; the loader reports an +// error if it detects an import cycle. +// +// Then, each package P for which testing is desired is augmented by +// the list P' of its in-package test files, by calling +// (*types.Checker).Files. This arrangement ensures that P' may +// reference definitions within P, but P may not reference definitions +// within P'. Furthermore, P' may import any other package, including +// ones that depend upon P, without an import cycle error. +// +// Consider two packages A and B, both of which have lists of +// in-package test files we'll call A' and B', and which have the +// following import graph edges: +// B imports A +// B' imports A +// A' imports B +// This last edge would be expected to create an error were it not +// for the special type-checking discipline above. +// Cycles of size greater than two are possible. For example: +// compress/bzip2/bzip2_test.go (package bzip2) imports "io/ioutil" +// io/ioutil/tempfile_test.go (package ioutil) imports "regexp" +// regexp/exec_test.go (package regexp) imports "compress/bzip2" +// +// +// Concurrency +// ----------- +// +// Let us define the import dependency graph as follows. Each node is a +// list of files passed to (Checker).Files at once. Many of these lists +// are the production code of an importable Go package, so those nodes +// are labelled by the package's path. The remaining nodes are +// ad hoc packages and lists of in-package *_test.go files that augment +// an importable package; those nodes have no label. +// +// The edges of the graph represent import statements appearing within a +// file. An edge connects a node (a list of files) to the node it +// imports, which is importable and thus always labelled. +// +// Loading is controlled by this dependency graph. +// +// To reduce I/O latency, we start loading a package's dependencies +// asynchronously as soon as we've parsed its files and enumerated its +// imports (scanImports). This performs a preorder traversal of the +// import dependency graph. +// +// To exploit hardware parallelism, we type-check unrelated packages in +// parallel, where "unrelated" means not ordered by the partial order of +// the import dependency graph. +// +// We use a concurrency-safe non-blocking cache (importer.imported) to +// record the results of type-checking, whether success or failure. An +// entry is created in this cache by startLoad the first time the +// package is imported. The first goroutine to request an entry becomes +// responsible for completing the task and broadcasting completion to +// subsequent requestors, which block until then. +// +// Type checking occurs in (parallel) postorder: we cannot type-check a +// set of files until we have loaded and type-checked all of their +// immediate dependencies (and thus all of their transitive +// dependencies). If the input were guaranteed free of import cycles, +// this would be trivial: we could simply wait for completion of the +// dependencies and then invoke the typechecker. +// +// But as we saw in the 'go test' section above, some cycles in the +// import graph over packages are actually legal, so long as the +// cycle-forming edge originates in the in-package test files that +// augment the package. This explains why the nodes of the import +// dependency graph are not packages, but lists of files: the unlabelled +// nodes avoid the cycles. Consider packages A and B where B imports A +// and A's in-package tests AT import B. The naively constructed import +// graph over packages would contain a cycle (A+AT) --> B --> (A+AT) but +// the graph over lists of files is AT --> B --> A, where AT is an +// unlabelled node. +// +// Awaiting completion of the dependencies in a cyclic graph would +// deadlock, so we must materialize the import dependency graph (as +// importer.graph) and check whether each import edge forms a cycle. If +// x imports y, and the graph already contains a path from y to x, then +// there is an import cycle, in which case the processing of x must not +// wait for the completion of processing of y. +// +// When the type-checker makes a callback (doImport) to the loader for a +// given import edge, there are two possible cases. In the normal case, +// the dependency has already been completely type-checked; doImport +// does a cache lookup and returns it. In the cyclic case, the entry in +// the cache is still necessarily incomplete, indicating a cycle. We +// perform the cycle check again to obtain the error message, and return +// the error. +// +// The result of using concurrency is about a 2.5x speedup for stdlib_test. + +// TODO(adonovan): overhaul the package documentation. diff --git a/vendor/golang.org/x/tools/go/loader/loader.go b/vendor/golang.org/x/tools/go/loader/loader.go new file mode 100644 index 0000000000..c456661189 --- /dev/null +++ b/vendor/golang.org/x/tools/go/loader/loader.go @@ -0,0 +1,1078 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package loader + +// See doc.go for package documentation and implementation notes. + +import ( + "errors" + "fmt" + "go/ast" + "go/build" + "go/parser" + "go/token" + "go/types" + "os" + "path/filepath" + "sort" + "strings" + "sync" + "time" + + "golang.org/x/tools/go/ast/astutil" + "golang.org/x/tools/go/internal/cgo" +) + +var ignoreVendor build.ImportMode + +const trace = false // show timing info for type-checking + +// Config specifies the configuration for loading a whole program from +// Go source code. +// The zero value for Config is a ready-to-use default configuration. +type Config struct { + // Fset is the file set for the parser to use when loading the + // program. If nil, it may be lazily initialized by any + // method of Config. + Fset *token.FileSet + + // ParserMode specifies the mode to be used by the parser when + // loading source packages. + ParserMode parser.Mode + + // TypeChecker contains options relating to the type checker. + // + // The supplied IgnoreFuncBodies is not used; the effective + // value comes from the TypeCheckFuncBodies func below. + // The supplied Import function is not used either. + TypeChecker types.Config + + // TypeCheckFuncBodies is a predicate over package paths. + // A package for which the predicate is false will + // have its package-level declarations type checked, but not + // its function bodies; this can be used to quickly load + // dependencies from source. If nil, all func bodies are type + // checked. + TypeCheckFuncBodies func(path string) bool + + // If Build is non-nil, it is used to locate source packages. + // Otherwise &build.Default is used. + // + // By default, cgo is invoked to preprocess Go files that + // import the fake package "C". This behaviour can be + // disabled by setting CGO_ENABLED=0 in the environment prior + // to startup, or by setting Build.CgoEnabled=false. + Build *build.Context + + // The current directory, used for resolving relative package + // references such as "./go/loader". If empty, os.Getwd will be + // used instead. + Cwd string + + // If DisplayPath is non-nil, it is used to transform each + // file name obtained from Build.Import(). This can be used + // to prevent a virtualized build.Config's file names from + // leaking into the user interface. + DisplayPath func(path string) string + + // If AllowErrors is true, Load will return a Program even + // if some of the its packages contained I/O, parser or type + // errors; such errors are accessible via PackageInfo.Errors. If + // false, Load will fail if any package had an error. + AllowErrors bool + + // CreatePkgs specifies a list of non-importable initial + // packages to create. The resulting packages will appear in + // the corresponding elements of the Program.Created slice. + CreatePkgs []PkgSpec + + // ImportPkgs specifies a set of initial packages to load. + // The map keys are package paths. + // + // The map value indicates whether to load tests. If true, Load + // will add and type-check two lists of files to the package: + // non-test files followed by in-package *_test.go files. In + // addition, it will append the external test package (if any) + // to Program.Created. + ImportPkgs map[string]bool + + // FindPackage is called during Load to create the build.Package + // for a given import path from a given directory. + // If FindPackage is nil, (*build.Context).Import is used. + // A client may use this hook to adapt to a proprietary build + // system that does not follow the "go build" layout + // conventions, for example. + // + // It must be safe to call concurrently from multiple goroutines. + FindPackage func(ctxt *build.Context, importPath, fromDir string, mode build.ImportMode) (*build.Package, error) + + // AfterTypeCheck is called immediately after a list of files + // has been type-checked and appended to info.Files. + // + // This optional hook function is the earliest opportunity for + // the client to observe the output of the type checker, + // which may be useful to reduce analysis latency when loading + // a large program. + // + // The function is permitted to modify info.Info, for instance + // to clear data structures that are no longer needed, which can + // dramatically reduce peak memory consumption. + // + // The function may be called twice for the same PackageInfo: + // once for the files of the package and again for the + // in-package test files. + // + // It must be safe to call concurrently from multiple goroutines. + AfterTypeCheck func(info *PackageInfo, files []*ast.File) +} + +// A PkgSpec specifies a non-importable package to be created by Load. +// Files are processed first, but typically only one of Files and +// Filenames is provided. The path needn't be globally unique. +// +// For vendoring purposes, the package's directory is the one that +// contains the first file. +type PkgSpec struct { + Path string // package path ("" => use package declaration) + Files []*ast.File // ASTs of already-parsed files + Filenames []string // names of files to be parsed +} + +// A Program is a Go program loaded from source as specified by a Config. +type Program struct { + Fset *token.FileSet // the file set for this program + + // Created[i] contains the initial package whose ASTs or + // filenames were supplied by Config.CreatePkgs[i], followed by + // the external test package, if any, of each package in + // Config.ImportPkgs ordered by ImportPath. + // + // NOTE: these files must not import "C". Cgo preprocessing is + // only performed on imported packages, not ad hoc packages. + // + // TODO(adonovan): we need to copy and adapt the logic of + // goFilesPackage (from $GOROOT/src/cmd/go/build.go) and make + // Config.Import and Config.Create methods return the same kind + // of entity, essentially a build.Package. + // Perhaps we can even reuse that type directly. + Created []*PackageInfo + + // Imported contains the initially imported packages, + // as specified by Config.ImportPkgs. + Imported map[string]*PackageInfo + + // AllPackages contains the PackageInfo of every package + // encountered by Load: all initial packages and all + // dependencies, including incomplete ones. + AllPackages map[*types.Package]*PackageInfo + + // importMap is the canonical mapping of package paths to + // packages. It contains all Imported initial packages, but not + // Created ones, and all imported dependencies. + importMap map[string]*types.Package +} + +// PackageInfo holds the ASTs and facts derived by the type-checker +// for a single package. +// +// Not mutated once exposed via the API. +// +type PackageInfo struct { + Pkg *types.Package + Importable bool // true if 'import "Pkg.Path()"' would resolve to this + TransitivelyErrorFree bool // true if Pkg and all its dependencies are free of errors + Files []*ast.File // syntax trees for the package's files + Errors []error // non-nil if the package had errors + types.Info // type-checker deductions. + dir string // package directory + + checker *types.Checker // transient type-checker state + errorFunc func(error) +} + +func (info *PackageInfo) String() string { return info.Pkg.Path() } + +func (info *PackageInfo) appendError(err error) { + if info.errorFunc != nil { + info.errorFunc(err) + } else { + fmt.Fprintln(os.Stderr, err) + } + info.Errors = append(info.Errors, err) +} + +func (conf *Config) fset() *token.FileSet { + if conf.Fset == nil { + conf.Fset = token.NewFileSet() + } + return conf.Fset +} + +// ParseFile is a convenience function (intended for testing) that invokes +// the parser using the Config's FileSet, which is initialized if nil. +// +// src specifies the parser input as a string, []byte, or io.Reader, and +// filename is its apparent name. If src is nil, the contents of +// filename are read from the file system. +// +func (conf *Config) ParseFile(filename string, src interface{}) (*ast.File, error) { + // TODO(adonovan): use conf.build() etc like parseFiles does. + return parser.ParseFile(conf.fset(), filename, src, conf.ParserMode) +} + +// FromArgsUsage is a partial usage message that applications calling +// FromArgs may wish to include in their -help output. +const FromArgsUsage = ` + is a list of arguments denoting a set of initial packages. +It may take one of two forms: + +1. A list of *.go source files. + + All of the specified files are loaded, parsed and type-checked + as a single package. All the files must belong to the same directory. + +2. A list of import paths, each denoting a package. + + The package's directory is found relative to the $GOROOT and + $GOPATH using similar logic to 'go build', and the *.go files in + that directory are loaded, parsed and type-checked as a single + package. + + In addition, all *_test.go files in the directory are then loaded + and parsed. Those files whose package declaration equals that of + the non-*_test.go files are included in the primary package. Test + files whose package declaration ends with "_test" are type-checked + as another package, the 'external' test package, so that a single + import path may denote two packages. (Whether this behaviour is + enabled is tool-specific, and may depend on additional flags.) + +A '--' argument terminates the list of packages. +` + +// FromArgs interprets args as a set of initial packages to load from +// source and updates the configuration. It returns the list of +// unconsumed arguments. +// +// It is intended for use in command-line interfaces that require a +// set of initial packages to be specified; see FromArgsUsage message +// for details. +// +// Only superficial errors are reported at this stage; errors dependent +// on I/O are detected during Load. +// +func (conf *Config) FromArgs(args []string, xtest bool) ([]string, error) { + var rest []string + for i, arg := range args { + if arg == "--" { + rest = args[i+1:] + args = args[:i] + break // consume "--" and return the remaining args + } + } + + if len(args) > 0 && strings.HasSuffix(args[0], ".go") { + // Assume args is a list of a *.go files + // denoting a single ad hoc package. + for _, arg := range args { + if !strings.HasSuffix(arg, ".go") { + return nil, fmt.Errorf("named files must be .go files: %s", arg) + } + } + conf.CreateFromFilenames("", args...) + } else { + // Assume args are directories each denoting a + // package and (perhaps) an external test, iff xtest. + for _, arg := range args { + if xtest { + conf.ImportWithTests(arg) + } else { + conf.Import(arg) + } + } + } + + return rest, nil +} + +// CreateFromFilenames is a convenience function that adds +// a conf.CreatePkgs entry to create a package of the specified *.go +// files. +// +func (conf *Config) CreateFromFilenames(path string, filenames ...string) { + conf.CreatePkgs = append(conf.CreatePkgs, PkgSpec{Path: path, Filenames: filenames}) +} + +// CreateFromFiles is a convenience function that adds a conf.CreatePkgs +// entry to create package of the specified path and parsed files. +// +func (conf *Config) CreateFromFiles(path string, files ...*ast.File) { + conf.CreatePkgs = append(conf.CreatePkgs, PkgSpec{Path: path, Files: files}) +} + +// ImportWithTests is a convenience function that adds path to +// ImportPkgs, the set of initial source packages located relative to +// $GOPATH. The package will be augmented by any *_test.go files in +// its directory that contain a "package x" (not "package x_test") +// declaration. +// +// In addition, if any *_test.go files contain a "package x_test" +// declaration, an additional package comprising just those files will +// be added to CreatePkgs. +// +func (conf *Config) ImportWithTests(path string) { conf.addImport(path, true) } + +// Import is a convenience function that adds path to ImportPkgs, the +// set of initial packages that will be imported from source. +// +func (conf *Config) Import(path string) { conf.addImport(path, false) } + +func (conf *Config) addImport(path string, tests bool) { + if path == "C" { + return // ignore; not a real package + } + if conf.ImportPkgs == nil { + conf.ImportPkgs = make(map[string]bool) + } + conf.ImportPkgs[path] = conf.ImportPkgs[path] || tests +} + +// PathEnclosingInterval returns the PackageInfo and ast.Node that +// contain source interval [start, end), and all the node's ancestors +// up to the AST root. It searches all ast.Files of all packages in prog. +// exact is defined as for astutil.PathEnclosingInterval. +// +// The zero value is returned if not found. +// +func (prog *Program) PathEnclosingInterval(start, end token.Pos) (pkg *PackageInfo, path []ast.Node, exact bool) { + for _, info := range prog.AllPackages { + for _, f := range info.Files { + if f.Pos() == token.NoPos { + // This can happen if the parser saw + // too many errors and bailed out. + // (Use parser.AllErrors to prevent that.) + continue + } + if !tokenFileContainsPos(prog.Fset.File(f.Pos()), start) { + continue + } + if path, exact := astutil.PathEnclosingInterval(f, start, end); path != nil { + return info, path, exact + } + } + } + return nil, nil, false +} + +// InitialPackages returns a new slice containing the set of initial +// packages (Created + Imported) in unspecified order. +// +func (prog *Program) InitialPackages() []*PackageInfo { + infos := make([]*PackageInfo, 0, len(prog.Created)+len(prog.Imported)) + infos = append(infos, prog.Created...) + for _, info := range prog.Imported { + infos = append(infos, info) + } + return infos +} + +// Package returns the ASTs and results of type checking for the +// specified package. +func (prog *Program) Package(path string) *PackageInfo { + if info, ok := prog.AllPackages[prog.importMap[path]]; ok { + return info + } + for _, info := range prog.Created { + if path == info.Pkg.Path() { + return info + } + } + return nil +} + +// ---------- Implementation ---------- + +// importer holds the working state of the algorithm. +type importer struct { + conf *Config // the client configuration + start time.Time // for logging + + progMu sync.Mutex // guards prog + prog *Program // the resulting program + + // findpkg is a memoization of FindPackage. + findpkgMu sync.Mutex // guards findpkg + findpkg map[findpkgKey]*findpkgValue + + importedMu sync.Mutex // guards imported + imported map[string]*importInfo // all imported packages (incl. failures) by import path + + // import dependency graph: graph[x][y] => x imports y + // + // Since non-importable packages cannot be cyclic, we ignore + // their imports, thus we only need the subgraph over importable + // packages. Nodes are identified by their import paths. + graphMu sync.Mutex + graph map[string]map[string]bool +} + +type findpkgKey struct { + importPath string + fromDir string + mode build.ImportMode +} + +type findpkgValue struct { + ready chan struct{} // closed to broadcast readiness + bp *build.Package + err error +} + +// importInfo tracks the success or failure of a single import. +// +// Upon completion, exactly one of info and err is non-nil: +// info on successful creation of a package, err otherwise. +// A successful package may still contain type errors. +// +type importInfo struct { + path string // import path + info *PackageInfo // results of typechecking (including errors) + complete chan struct{} // closed to broadcast that info is set. +} + +// awaitCompletion blocks until ii is complete, +// i.e. the info field is safe to inspect. +func (ii *importInfo) awaitCompletion() { + <-ii.complete // wait for close +} + +// Complete marks ii as complete. +// Its info and err fields will not be subsequently updated. +func (ii *importInfo) Complete(info *PackageInfo) { + if info == nil { + panic("info == nil") + } + ii.info = info + close(ii.complete) +} + +type importError struct { + path string // import path + err error // reason for failure to create a package +} + +// Load creates the initial packages specified by conf.{Create,Import}Pkgs, +// loading their dependencies packages as needed. +// +// On success, Load returns a Program containing a PackageInfo for +// each package. On failure, it returns an error. +// +// If AllowErrors is true, Load will return a Program even if some +// packages contained I/O, parser or type errors, or if dependencies +// were missing. (Such errors are accessible via PackageInfo.Errors. If +// false, Load will fail if any package had an error. +// +// It is an error if no packages were loaded. +// +func (conf *Config) Load() (*Program, error) { + // Create a simple default error handler for parse/type errors. + if conf.TypeChecker.Error == nil { + conf.TypeChecker.Error = func(e error) { fmt.Fprintln(os.Stderr, e) } + } + + // Set default working directory for relative package references. + if conf.Cwd == "" { + var err error + conf.Cwd, err = os.Getwd() + if err != nil { + return nil, err + } + } + + // Install default FindPackage hook using go/build logic. + if conf.FindPackage == nil { + conf.FindPackage = (*build.Context).Import + } + + prog := &Program{ + Fset: conf.fset(), + Imported: make(map[string]*PackageInfo), + importMap: make(map[string]*types.Package), + AllPackages: make(map[*types.Package]*PackageInfo), + } + + imp := importer{ + conf: conf, + prog: prog, + findpkg: make(map[findpkgKey]*findpkgValue), + imported: make(map[string]*importInfo), + start: time.Now(), + graph: make(map[string]map[string]bool), + } + + // -- loading proper (concurrent phase) -------------------------------- + + var errpkgs []string // packages that contained errors + + // Load the initially imported packages and their dependencies, + // in parallel. + // No vendor check on packages imported from the command line. + infos, importErrors := imp.importAll("", conf.Cwd, conf.ImportPkgs, ignoreVendor) + for _, ie := range importErrors { + conf.TypeChecker.Error(ie.err) // failed to create package + errpkgs = append(errpkgs, ie.path) + } + for _, info := range infos { + prog.Imported[info.Pkg.Path()] = info + } + + // Augment the designated initial packages by their tests. + // Dependencies are loaded in parallel. + var xtestPkgs []*build.Package + for importPath, augment := range conf.ImportPkgs { + if !augment { + continue + } + + // No vendor check on packages imported from command line. + bp, err := imp.findPackage(importPath, conf.Cwd, ignoreVendor) + if err != nil { + // Package not found, or can't even parse package declaration. + // Already reported by previous loop; ignore it. + continue + } + + // Needs external test package? + if len(bp.XTestGoFiles) > 0 { + xtestPkgs = append(xtestPkgs, bp) + } + + // Consult the cache using the canonical package path. + path := bp.ImportPath + imp.importedMu.Lock() // (unnecessary, we're sequential here) + ii, ok := imp.imported[path] + // Paranoid checks added due to issue #11012. + if !ok { + // Unreachable. + // The previous loop called importAll and thus + // startLoad for each path in ImportPkgs, which + // populates imp.imported[path] with a non-zero value. + panic(fmt.Sprintf("imported[%q] not found", path)) + } + if ii == nil { + // Unreachable. + // The ii values in this loop are the same as in + // the previous loop, which enforced the invariant + // that at least one of ii.err and ii.info is non-nil. + panic(fmt.Sprintf("imported[%q] == nil", path)) + } + if ii.info == nil { + // Unreachable. + // awaitCompletion has the postcondition + // ii.info != nil. + panic(fmt.Sprintf("imported[%q].info = nil", path)) + } + info := ii.info + imp.importedMu.Unlock() + + // Parse the in-package test files. + files, errs := imp.conf.parsePackageFiles(bp, 't') + for _, err := range errs { + info.appendError(err) + } + + // The test files augmenting package P cannot be imported, + // but may import packages that import P, + // so we must disable the cycle check. + imp.addFiles(info, files, false) + } + + createPkg := func(path, dir string, files []*ast.File, errs []error) { + info := imp.newPackageInfo(path, dir) + for _, err := range errs { + info.appendError(err) + } + + // Ad hoc packages are non-importable, + // so no cycle check is needed. + // addFiles loads dependencies in parallel. + imp.addFiles(info, files, false) + prog.Created = append(prog.Created, info) + } + + // Create packages specified by conf.CreatePkgs. + for _, cp := range conf.CreatePkgs { + files, errs := parseFiles(conf.fset(), conf.build(), nil, conf.Cwd, cp.Filenames, conf.ParserMode) + files = append(files, cp.Files...) + + path := cp.Path + if path == "" { + if len(files) > 0 { + path = files[0].Name.Name + } else { + path = "(unnamed)" + } + } + + dir := conf.Cwd + if len(files) > 0 && files[0].Pos().IsValid() { + dir = filepath.Dir(conf.fset().File(files[0].Pos()).Name()) + } + createPkg(path, dir, files, errs) + } + + // Create external test packages. + sort.Sort(byImportPath(xtestPkgs)) + for _, bp := range xtestPkgs { + files, errs := imp.conf.parsePackageFiles(bp, 'x') + createPkg(bp.ImportPath+"_test", bp.Dir, files, errs) + } + + // -- finishing up (sequential) ---------------------------------------- + + if len(prog.Imported)+len(prog.Created) == 0 { + return nil, errors.New("no initial packages were loaded") + } + + // Create infos for indirectly imported packages. + // e.g. incomplete packages without syntax, loaded from export data. + for _, obj := range prog.importMap { + info := prog.AllPackages[obj] + if info == nil { + prog.AllPackages[obj] = &PackageInfo{Pkg: obj, Importable: true} + } else { + // finished + info.checker = nil + info.errorFunc = nil + } + } + + if !conf.AllowErrors { + // Report errors in indirectly imported packages. + for _, info := range prog.AllPackages { + if len(info.Errors) > 0 { + errpkgs = append(errpkgs, info.Pkg.Path()) + } + } + if errpkgs != nil { + var more string + if len(errpkgs) > 3 { + more = fmt.Sprintf(" and %d more", len(errpkgs)-3) + errpkgs = errpkgs[:3] + } + return nil, fmt.Errorf("couldn't load packages due to errors: %s%s", + strings.Join(errpkgs, ", "), more) + } + } + + markErrorFreePackages(prog.AllPackages) + + return prog, nil +} + +type byImportPath []*build.Package + +func (b byImportPath) Len() int { return len(b) } +func (b byImportPath) Less(i, j int) bool { return b[i].ImportPath < b[j].ImportPath } +func (b byImportPath) Swap(i, j int) { b[i], b[j] = b[j], b[i] } + +// markErrorFreePackages sets the TransitivelyErrorFree flag on all +// applicable packages. +func markErrorFreePackages(allPackages map[*types.Package]*PackageInfo) { + // Build the transpose of the import graph. + importedBy := make(map[*types.Package]map[*types.Package]bool) + for P := range allPackages { + for _, Q := range P.Imports() { + clients, ok := importedBy[Q] + if !ok { + clients = make(map[*types.Package]bool) + importedBy[Q] = clients + } + clients[P] = true + } + } + + // Find all packages reachable from some error package. + reachable := make(map[*types.Package]bool) + var visit func(*types.Package) + visit = func(p *types.Package) { + if !reachable[p] { + reachable[p] = true + for q := range importedBy[p] { + visit(q) + } + } + } + for _, info := range allPackages { + if len(info.Errors) > 0 { + visit(info.Pkg) + } + } + + // Mark the others as "transitively error-free". + for _, info := range allPackages { + if !reachable[info.Pkg] { + info.TransitivelyErrorFree = true + } + } +} + +// build returns the effective build context. +func (conf *Config) build() *build.Context { + if conf.Build != nil { + return conf.Build + } + return &build.Default +} + +// parsePackageFiles enumerates the files belonging to package path, +// then loads, parses and returns them, plus a list of I/O or parse +// errors that were encountered. +// +// 'which' indicates which files to include: +// 'g': include non-test *.go source files (GoFiles + processed CgoFiles) +// 't': include in-package *_test.go source files (TestGoFiles) +// 'x': include external *_test.go source files. (XTestGoFiles) +// +func (conf *Config) parsePackageFiles(bp *build.Package, which rune) ([]*ast.File, []error) { + if bp.ImportPath == "unsafe" { + return nil, nil + } + var filenames []string + switch which { + case 'g': + filenames = bp.GoFiles + case 't': + filenames = bp.TestGoFiles + case 'x': + filenames = bp.XTestGoFiles + default: + panic(which) + } + + files, errs := parseFiles(conf.fset(), conf.build(), conf.DisplayPath, bp.Dir, filenames, conf.ParserMode) + + // Preprocess CgoFiles and parse the outputs (sequentially). + if which == 'g' && bp.CgoFiles != nil { + cgofiles, err := cgo.ProcessFiles(bp, conf.fset(), conf.DisplayPath, conf.ParserMode) + if err != nil { + errs = append(errs, err) + } else { + files = append(files, cgofiles...) + } + } + + return files, errs +} + +// doImport imports the package denoted by path. +// It implements the types.Importer signature. +// +// It returns an error if a package could not be created +// (e.g. go/build or parse error), but type errors are reported via +// the types.Config.Error callback (the first of which is also saved +// in the package's PackageInfo). +// +// Idempotent. +// +func (imp *importer) doImport(from *PackageInfo, to string) (*types.Package, error) { + if to == "C" { + // This should be unreachable, but ad hoc packages are + // not currently subject to cgo preprocessing. + // See https://github.com/golang/go/issues/11627. + return nil, fmt.Errorf(`the loader doesn't cgo-process ad hoc packages like %q; see Go issue 11627`, + from.Pkg.Path()) + } + + bp, err := imp.findPackage(to, from.dir, 0) + if err != nil { + return nil, err + } + + // The standard unsafe package is handled specially, + // and has no PackageInfo. + if bp.ImportPath == "unsafe" { + return types.Unsafe, nil + } + + // Look for the package in the cache using its canonical path. + path := bp.ImportPath + imp.importedMu.Lock() + ii := imp.imported[path] + imp.importedMu.Unlock() + if ii == nil { + panic("internal error: unexpected import: " + path) + } + if ii.info != nil { + return ii.info.Pkg, nil + } + + // Import of incomplete package: this indicates a cycle. + fromPath := from.Pkg.Path() + if cycle := imp.findPath(path, fromPath); cycle != nil { + cycle = append([]string{fromPath}, cycle...) + return nil, fmt.Errorf("import cycle: %s", strings.Join(cycle, " -> ")) + } + + panic("internal error: import of incomplete (yet acyclic) package: " + fromPath) +} + +// findPackage locates the package denoted by the importPath in the +// specified directory. +func (imp *importer) findPackage(importPath, fromDir string, mode build.ImportMode) (*build.Package, error) { + // We use a non-blocking duplicate-suppressing cache (gopl.io §9.7) + // to avoid holding the lock around FindPackage. + key := findpkgKey{importPath, fromDir, mode} + imp.findpkgMu.Lock() + v, ok := imp.findpkg[key] + if ok { + // cache hit + imp.findpkgMu.Unlock() + + <-v.ready // wait for entry to become ready + } else { + // Cache miss: this goroutine becomes responsible for + // populating the map entry and broadcasting its readiness. + v = &findpkgValue{ready: make(chan struct{})} + imp.findpkg[key] = v + imp.findpkgMu.Unlock() + + ioLimit <- true + v.bp, v.err = imp.conf.FindPackage(imp.conf.build(), importPath, fromDir, mode) + <-ioLimit + + if _, ok := v.err.(*build.NoGoError); ok { + v.err = nil // empty directory is not an error + } + + close(v.ready) // broadcast ready condition + } + return v.bp, v.err +} + +// importAll loads, parses, and type-checks the specified packages in +// parallel and returns their completed importInfos in unspecified order. +// +// fromPath is the package path of the importing package, if it is +// importable, "" otherwise. It is used for cycle detection. +// +// fromDir is the directory containing the import declaration that +// caused these imports. +// +func (imp *importer) importAll(fromPath, fromDir string, imports map[string]bool, mode build.ImportMode) (infos []*PackageInfo, errors []importError) { + // TODO(adonovan): opt: do the loop in parallel once + // findPackage is non-blocking. + var pending []*importInfo + for importPath := range imports { + bp, err := imp.findPackage(importPath, fromDir, mode) + if err != nil { + errors = append(errors, importError{ + path: importPath, + err: err, + }) + continue + } + pending = append(pending, imp.startLoad(bp)) + } + + if fromPath != "" { + // We're loading a set of imports. + // + // We must record graph edges from the importing package + // to its dependencies, and check for cycles. + imp.graphMu.Lock() + deps, ok := imp.graph[fromPath] + if !ok { + deps = make(map[string]bool) + imp.graph[fromPath] = deps + } + for _, ii := range pending { + deps[ii.path] = true + } + imp.graphMu.Unlock() + } + + for _, ii := range pending { + if fromPath != "" { + if cycle := imp.findPath(ii.path, fromPath); cycle != nil { + // Cycle-forming import: we must not await its + // completion since it would deadlock. + // + // We don't record the error in ii since + // the error is really associated with the + // cycle-forming edge, not the package itself. + // (Also it would complicate the + // invariants of importPath completion.) + if trace { + fmt.Fprintf(os.Stderr, "import cycle: %q\n", cycle) + } + continue + } + } + ii.awaitCompletion() + infos = append(infos, ii.info) + } + + return infos, errors +} + +// findPath returns an arbitrary path from 'from' to 'to' in the import +// graph, or nil if there was none. +func (imp *importer) findPath(from, to string) []string { + imp.graphMu.Lock() + defer imp.graphMu.Unlock() + + seen := make(map[string]bool) + var search func(stack []string, importPath string) []string + search = func(stack []string, importPath string) []string { + if !seen[importPath] { + seen[importPath] = true + stack = append(stack, importPath) + if importPath == to { + return stack + } + for x := range imp.graph[importPath] { + if p := search(stack, x); p != nil { + return p + } + } + } + return nil + } + return search(make([]string, 0, 20), from) +} + +// startLoad initiates the loading, parsing and type-checking of the +// specified package and its dependencies, if it has not already begun. +// +// It returns an importInfo, not necessarily in a completed state. The +// caller must call awaitCompletion() before accessing its info field. +// +// startLoad is concurrency-safe and idempotent. +// +func (imp *importer) startLoad(bp *build.Package) *importInfo { + path := bp.ImportPath + imp.importedMu.Lock() + ii, ok := imp.imported[path] + if !ok { + ii = &importInfo{path: path, complete: make(chan struct{})} + imp.imported[path] = ii + go func() { + info := imp.load(bp) + ii.Complete(info) + }() + } + imp.importedMu.Unlock() + + return ii +} + +// load implements package loading by parsing Go source files +// located by go/build. +func (imp *importer) load(bp *build.Package) *PackageInfo { + info := imp.newPackageInfo(bp.ImportPath, bp.Dir) + info.Importable = true + files, errs := imp.conf.parsePackageFiles(bp, 'g') + for _, err := range errs { + info.appendError(err) + } + + imp.addFiles(info, files, true) + + imp.progMu.Lock() + imp.prog.importMap[bp.ImportPath] = info.Pkg + imp.progMu.Unlock() + + return info +} + +// addFiles adds and type-checks the specified files to info, loading +// their dependencies if needed. The order of files determines the +// package initialization order. It may be called multiple times on the +// same package. Errors are appended to the info.Errors field. +// +// cycleCheck determines whether the imports within files create +// dependency edges that should be checked for potential cycles. +// +func (imp *importer) addFiles(info *PackageInfo, files []*ast.File, cycleCheck bool) { + // Ensure the dependencies are loaded, in parallel. + var fromPath string + if cycleCheck { + fromPath = info.Pkg.Path() + } + // TODO(adonovan): opt: make the caller do scanImports. + // Callers with a build.Package can skip it. + imp.importAll(fromPath, info.dir, scanImports(files), 0) + + if trace { + fmt.Fprintf(os.Stderr, "%s: start %q (%d)\n", + time.Since(imp.start), info.Pkg.Path(), len(files)) + } + + // Don't call checker.Files on Unsafe, even with zero files, + // because it would mutate the package, which is a global. + if info.Pkg == types.Unsafe { + if len(files) > 0 { + panic(`"unsafe" package contains unexpected files`) + } + } else { + // Ignore the returned (first) error since we + // already collect them all in the PackageInfo. + info.checker.Files(files) + info.Files = append(info.Files, files...) + } + + if imp.conf.AfterTypeCheck != nil { + imp.conf.AfterTypeCheck(info, files) + } + + if trace { + fmt.Fprintf(os.Stderr, "%s: stop %q\n", + time.Since(imp.start), info.Pkg.Path()) + } +} + +func (imp *importer) newPackageInfo(path, dir string) *PackageInfo { + var pkg *types.Package + if path == "unsafe" { + pkg = types.Unsafe + } else { + pkg = types.NewPackage(path, "") + } + info := &PackageInfo{ + Pkg: pkg, + Info: types.Info{ + Types: make(map[ast.Expr]types.TypeAndValue), + Defs: make(map[*ast.Ident]types.Object), + Uses: make(map[*ast.Ident]types.Object), + Implicits: make(map[ast.Node]types.Object), + Scopes: make(map[ast.Node]*types.Scope), + Selections: make(map[*ast.SelectorExpr]*types.Selection), + }, + errorFunc: imp.conf.TypeChecker.Error, + dir: dir, + } + + // Copy the types.Config so we can vary it across PackageInfos. + tc := imp.conf.TypeChecker + tc.IgnoreFuncBodies = false + if f := imp.conf.TypeCheckFuncBodies; f != nil { + tc.IgnoreFuncBodies = !f(path) + } + tc.Importer = closure{imp, info} + tc.Error = info.appendError // appendError wraps the user's Error function + + info.checker = types.NewChecker(&tc, imp.conf.fset(), pkg, &info.Info) + imp.progMu.Lock() + imp.prog.AllPackages[pkg] = info + imp.progMu.Unlock() + return info +} + +type closure struct { + imp *importer + info *PackageInfo +} + +func (c closure) Import(to string) (*types.Package, error) { return c.imp.doImport(c.info, to) } diff --git a/vendor/golang.org/x/tools/go/loader/util.go b/vendor/golang.org/x/tools/go/loader/util.go new file mode 100644 index 0000000000..7f38dd7407 --- /dev/null +++ b/vendor/golang.org/x/tools/go/loader/util.go @@ -0,0 +1,124 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package loader + +import ( + "go/ast" + "go/build" + "go/parser" + "go/token" + "io" + "os" + "strconv" + "sync" + + "golang.org/x/tools/go/buildutil" +) + +// We use a counting semaphore to limit +// the number of parallel I/O calls per process. +var ioLimit = make(chan bool, 10) + +// parseFiles parses the Go source files within directory dir and +// returns the ASTs of the ones that could be at least partially parsed, +// along with a list of I/O and parse errors encountered. +// +// I/O is done via ctxt, which may specify a virtual file system. +// displayPath is used to transform the filenames attached to the ASTs. +// +func parseFiles(fset *token.FileSet, ctxt *build.Context, displayPath func(string) string, dir string, files []string, mode parser.Mode) ([]*ast.File, []error) { + if displayPath == nil { + displayPath = func(path string) string { return path } + } + var wg sync.WaitGroup + n := len(files) + parsed := make([]*ast.File, n) + errors := make([]error, n) + for i, file := range files { + if !buildutil.IsAbsPath(ctxt, file) { + file = buildutil.JoinPath(ctxt, dir, file) + } + wg.Add(1) + go func(i int, file string) { + ioLimit <- true // wait + defer func() { + wg.Done() + <-ioLimit // signal + }() + var rd io.ReadCloser + var err error + if ctxt.OpenFile != nil { + rd, err = ctxt.OpenFile(file) + } else { + rd, err = os.Open(file) + } + if err != nil { + errors[i] = err // open failed + return + } + + // ParseFile may return both an AST and an error. + parsed[i], errors[i] = parser.ParseFile(fset, displayPath(file), rd, mode) + rd.Close() + }(i, file) + } + wg.Wait() + + // Eliminate nils, preserving order. + var o int + for _, f := range parsed { + if f != nil { + parsed[o] = f + o++ + } + } + parsed = parsed[:o] + + o = 0 + for _, err := range errors { + if err != nil { + errors[o] = err + o++ + } + } + errors = errors[:o] + + return parsed, errors +} + +// scanImports returns the set of all import paths from all +// import specs in the specified files. +func scanImports(files []*ast.File) map[string]bool { + imports := make(map[string]bool) + for _, f := range files { + for _, decl := range f.Decls { + if decl, ok := decl.(*ast.GenDecl); ok && decl.Tok == token.IMPORT { + for _, spec := range decl.Specs { + spec := spec.(*ast.ImportSpec) + + // NB: do not assume the program is well-formed! + path, err := strconv.Unquote(spec.Path.Value) + if err != nil { + continue // quietly ignore the error + } + if path == "C" { + continue // skip pseudopackage + } + imports[path] = true + } + } + } + } + return imports +} + +// ---------- Internal helpers ---------- + +// TODO(adonovan): make this a method: func (*token.File) Contains(token.Pos) +func tokenFileContainsPos(f *token.File, pos token.Pos) bool { + p := int(pos) + base := f.Base() + return base <= p && p < base+f.Size() +} diff --git a/vendor/golang.org/x/tools/go/packages/doc.go b/vendor/golang.org/x/tools/go/packages/doc.go new file mode 100644 index 0000000000..f9dd1b0237 --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/doc.go @@ -0,0 +1,241 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +/* +Package packages loads Go packages for inspection and analysis. + +Note: Though this package is ready for widespread use, we may make minor +breaking changes if absolutely necessary. Any such change will be +announced on golang-tools@ at least one week before it is committed. No +more breaking changes will be made after December 1, 2018. + +The Load function takes as input a list of patterns and return a list of Package +structs describing individual packages matched by those patterns. +The LoadMode controls the amount of detail in the loaded packages. + +Load passes most patterns directly to the underlying build tool, +but all patterns with the prefix "query=", where query is a +non-empty string of letters from [a-z], are reserved and may be +interpreted as query operators. + +Only two query operators are currently supported, "file" and "pattern". + +The query "file=path/to/file.go" matches the package or packages enclosing +the Go source file path/to/file.go. For example "file=~/go/src/fmt/print.go" +might returns the packages "fmt" and "fmt [fmt.test]". + +The query "pattern=string" causes "string" to be passed directly to +the underlying build tool. In most cases this is unnecessary, +but an application can use Load("pattern=" + x) as an escaping mechanism +to ensure that x is not interpreted as a query operator if it contains '='. + +A third query "name=identifier" will be added soon. +It will match packages whose package declaration contains the specified identifier. +For example, "name=rand" would match the packages "math/rand" and "crypto/rand", +and "name=main" would match all executables. + +All other query operators are reserved for future use and currently +cause Load to report an error. + +The Package struct provides basic information about the package, including + + - ID, a unique identifier for the package in the returned set; + - GoFiles, the names of the package's Go source files; + - Imports, a map from source import strings to the Packages they name; + - Types, the type information for the package's exported symbols; + - Syntax, the parsed syntax trees for the package's source code; and + - TypeInfo, the result of a complete type-check of the package syntax trees. + +(See the documentation for type Package for the complete list of fields +and more detailed descriptions.) + +For example, + + Load(nil, "bytes", "unicode...") + +returns four Package structs describing the standard library packages +bytes, unicode, unicode/utf16, and unicode/utf8. Note that one pattern +can match multiple packages and that a package might be matched by +multiple patterns: in general it is not possible to determine which +packages correspond to which patterns. + +Note that the list returned by Load contains only the packages matched +by the patterns. Their dependencies can be found by walking the import +graph using the Imports fields. + +The Load function can be configured by passing a pointer to a Config as +the first argument. A nil Config is equivalent to the zero Config, which +causes Load to run in LoadFiles mode, collecting minimal information. +See the documentation for type Config for details. + +As noted earlier, the Config.Mode controls the amount of detail +reported about the loaded packages, with each mode returning all the data of the +previous mode with some extra added. See the documentation for type LoadMode +for details. + +Most tools should pass their command-line arguments (after any flags) +uninterpreted to the loader, so that the loader can interpret them +according to the conventions of the underlying build system. +See the Example function for typical usage. + +*/ +package packages // import "golang.org/x/tools/go/packages" + +/* + +Motivation and design considerations + +The new package's design solves problems addressed by two existing +packages: go/build, which locates and describes packages, and +golang.org/x/tools/go/loader, which loads, parses and type-checks them. +The go/build.Package structure encodes too much of the 'go build' way +of organizing projects, leaving us in need of a data type that describes a +package of Go source code independent of the underlying build system. +We wanted something that works equally well with go build and vgo, and +also other build systems such as Bazel and Blaze, making it possible to +construct analysis tools that work in all these environments. +Tools such as errcheck and staticcheck were essentially unavailable to +the Go community at Google, and some of Google's internal tools for Go +are unavailable externally. +This new package provides a uniform way to obtain package metadata by +querying each of these build systems, optionally supporting their +preferred command-line notations for packages, so that tools integrate +neatly with users' build environments. The Metadata query function +executes an external query tool appropriate to the current workspace. + +Loading packages always returns the complete import graph "all the way down", +even if all you want is information about a single package, because the query +mechanisms of all the build systems we currently support ({go,vgo} list, and +blaze/bazel aspect-based query) cannot provide detailed information +about one package without visiting all its dependencies too, so there is +no additional asymptotic cost to providing transitive information. +(This property might not be true of a hypothetical 5th build system.) + +In calls to TypeCheck, all initial packages, and any package that +transitively depends on one of them, must be loaded from source. +Consider A->B->C->D->E: if A,C are initial, A,B,C must be loaded from +source; D may be loaded from export data, and E may not be loaded at all +(though it's possible that D's export data mentions it, so a +types.Package may be created for it and exposed.) + +The old loader had a feature to suppress type-checking of function +bodies on a per-package basis, primarily intended to reduce the work of +obtaining type information for imported packages. Now that imports are +satisfied by export data, the optimization no longer seems necessary. + +Despite some early attempts, the old loader did not exploit export data, +instead always using the equivalent of WholeProgram mode. This was due +to the complexity of mixing source and export data packages (now +resolved by the upward traversal mentioned above), and because export data +files were nearly always missing or stale. Now that 'go build' supports +caching, all the underlying build systems can guarantee to produce +export data in a reasonable (amortized) time. + +Test "main" packages synthesized by the build system are now reported as +first-class packages, avoiding the need for clients (such as go/ssa) to +reinvent this generation logic. + +One way in which go/packages is simpler than the old loader is in its +treatment of in-package tests. In-package tests are packages that +consist of all the files of the library under test, plus the test files. +The old loader constructed in-package tests by a two-phase process of +mutation called "augmentation": first it would construct and type check +all the ordinary library packages and type-check the packages that +depend on them; then it would add more (test) files to the package and +type-check again. This two-phase approach had four major problems: +1) in processing the tests, the loader modified the library package, + leaving no way for a client application to see both the test + package and the library package; one would mutate into the other. +2) because test files can declare additional methods on types defined in + the library portion of the package, the dispatch of method calls in + the library portion was affected by the presence of the test files. + This should have been a clue that the packages were logically + different. +3) this model of "augmentation" assumed at most one in-package test + per library package, which is true of projects using 'go build', + but not other build systems. +4) because of the two-phase nature of test processing, all packages that + import the library package had to be processed before augmentation, + forcing a "one-shot" API and preventing the client from calling Load + in several times in sequence as is now possible in WholeProgram mode. + (TypeCheck mode has a similar one-shot restriction for a different reason.) + +Early drafts of this package supported "multi-shot" operation. +Although it allowed clients to make a sequence of calls (or concurrent +calls) to Load, building up the graph of Packages incrementally, +it was of marginal value: it complicated the API +(since it allowed some options to vary across calls but not others), +it complicated the implementation, +it cannot be made to work in Types mode, as explained above, +and it was less efficient than making one combined call (when this is possible). +Among the clients we have inspected, none made multiple calls to load +but could not be easily and satisfactorily modified to make only a single call. +However, applications changes may be required. +For example, the ssadump command loads the user-specified packages +and in addition the runtime package. It is tempting to simply append +"runtime" to the user-provided list, but that does not work if the user +specified an ad-hoc package such as [a.go b.go]. +Instead, ssadump no longer requests the runtime package, +but seeks it among the dependencies of the user-specified packages, +and emits an error if it is not found. + +Overlays: the ParseFile hook in the API permits clients to vary the way +in which ASTs are obtained from filenames; the default implementation is +based on parser.ParseFile. This features enables editor-integrated tools +that analyze the contents of modified but unsaved buffers: rather than +read from the file system, a tool can read from an archive of modified +buffers provided by the editor. +This approach has its limits. Because package metadata is obtained by +fork/execing an external query command for each build system, we can +fake only the file contents seen by the parser, type-checker, and +application, but not by the metadata query, so, for example: +- additional imports in the fake file will not be described by the + metadata, so the type checker will fail to load imports that create + new dependencies. +- in TypeCheck mode, because export data is produced by the query + command, it will not reflect the fake file contents. +- this mechanism cannot add files to a package without first saving them. + +Questions & Tasks + +- Add GOARCH/GOOS? + They are not portable concepts, but could be made portable. + Our goal has been to allow users to express themselves using the conventions + of the underlying build system: if the build system honors GOARCH + during a build and during a metadata query, then so should + applications built atop that query mechanism. + Conversely, if the target architecture of the build is determined by + command-line flags, the application can pass the relevant + flags through to the build system using a command such as: + myapp -query_flag="--cpu=amd64" -query_flag="--os=darwin" + However, this approach is low-level, unwieldy, and non-portable. + GOOS and GOARCH seem important enough to warrant a dedicated option. + +- How should we handle partial failures such as a mixture of good and + malformed patterns, existing and non-existent packages, successful and + failed builds, import failures, import cycles, and so on, in a call to + Load? + +- Support bazel, blaze, and go1.10 list, not just go1.11 list. + +- Handle (and test) various partial success cases, e.g. + a mixture of good packages and: + invalid patterns + nonexistent packages + empty packages + packages with malformed package or import declarations + unreadable files + import cycles + other parse errors + type errors + Make sure we record errors at the correct place in the graph. + +- Missing packages among initial arguments are not reported. + Return bogus packages for them, like golist does. + +- "undeclared name" errors (for example) are reported out of source file + order. I suspect this is due to the breadth-first resolution now used + by go/types. Is that a bug? Discuss with gri. + +*/ diff --git a/vendor/golang.org/x/tools/go/packages/external.go b/vendor/golang.org/x/tools/go/packages/external.go new file mode 100644 index 0000000000..53cc080d9d --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/external.go @@ -0,0 +1,68 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file enables an external tool to intercept package requests. +// If the tool is present then its results are used in preference to +// the go list command. + +package packages + +import ( + "bytes" + "encoding/json" + "fmt" + "os/exec" + "strings" +) + +// findExternalTool returns the file path of a tool that supplies +// the build system package structure, or "" if not found." +// If GOPACKAGESDRIVER is set in the environment findExternalTool returns its +// value, otherwise it searches for a binary named gopackagesdriver on the PATH. +func findExternalDriver(cfg *Config) driver { + const toolPrefix = "GOPACKAGESDRIVER=" + tool := "" + for _, env := range cfg.Env { + if val := strings.TrimPrefix(env, toolPrefix); val != env { + tool = val + } + } + if tool != "" && tool == "off" { + return nil + } + if tool == "" { + var err error + tool, err = exec.LookPath("gopackagesdriver") + if err != nil { + return nil + } + } + return func(cfg *Config, words ...string) (*driverResponse, error) { + buf := new(bytes.Buffer) + fullargs := []string{ + "list", + fmt.Sprintf("-test=%t", cfg.Tests), + fmt.Sprintf("-export=%t", usesExportData(cfg)), + fmt.Sprintf("-deps=%t", cfg.Mode >= LoadImports), + } + for _, f := range cfg.BuildFlags { + fullargs = append(fullargs, fmt.Sprintf("-buildflag=%v", f)) + } + fullargs = append(fullargs, "--") + fullargs = append(fullargs, words...) + cmd := exec.CommandContext(cfg.Context, tool, fullargs...) + cmd.Env = cfg.Env + cmd.Dir = cfg.Dir + cmd.Stdout = buf + cmd.Stderr = new(bytes.Buffer) + if err := cmd.Run(); err != nil { + return nil, fmt.Errorf("%v: %v: %s", tool, err, cmd.Stderr) + } + var response driverResponse + if err := json.Unmarshal(buf.Bytes(), &response); err != nil { + return nil, err + } + return &response, nil + } +} diff --git a/vendor/golang.org/x/tools/go/packages/golist.go b/vendor/golang.org/x/tools/go/packages/golist.go new file mode 100644 index 0000000000..a1e9c320e3 --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/golist.go @@ -0,0 +1,625 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package packages + +import ( + "bytes" + "encoding/json" + "fmt" + "io/ioutil" + "log" + "os" + "os/exec" + "path/filepath" + "regexp" + "strings" + "sync" + + "golang.org/x/tools/internal/gopathwalk" + "golang.org/x/tools/internal/semver" +) + +// A goTooOldError reports that the go command +// found by exec.LookPath is too old to use the new go list behavior. +type goTooOldError struct { + error +} + +// goListDriver uses the go list command to interpret the patterns and produce +// the build system package structure. +// See driver for more details. +func goListDriver(cfg *Config, patterns ...string) (*driverResponse, error) { + // Determine files requested in contains patterns + var containFiles []string + var packagesNamed []string + restPatterns := make([]string, 0, len(patterns)) + // Extract file= and other [querytype]= patterns. Report an error if querytype + // doesn't exist. +extractQueries: + for _, pattern := range patterns { + eqidx := strings.Index(pattern, "=") + if eqidx < 0 { + restPatterns = append(restPatterns, pattern) + } else { + query, value := pattern[:eqidx], pattern[eqidx+len("="):] + switch query { + case "file": + containFiles = append(containFiles, value) + case "pattern": + restPatterns = append(restPatterns, value) + case "name": + packagesNamed = append(packagesNamed, value) + case "": // not a reserved query + restPatterns = append(restPatterns, pattern) + default: + for _, rune := range query { + if rune < 'a' || rune > 'z' { // not a reserved query + restPatterns = append(restPatterns, pattern) + continue extractQueries + } + } + // Reject all other patterns containing "=" + return nil, fmt.Errorf("invalid query type %q in query pattern %q", query, pattern) + } + } + } + patterns = restPatterns + // Look for the deprecated contains: syntax. + // TODO(matloob): delete this around mid-October 2018. + restPatterns = restPatterns[:0] + for _, pattern := range patterns { + if strings.HasPrefix(pattern, "contains:") { + containFile := strings.TrimPrefix(pattern, "contains:") + containFiles = append(containFiles, containFile) + } else { + restPatterns = append(restPatterns, pattern) + } + } + containFiles = absJoin(cfg.Dir, containFiles) + + // TODO(matloob): Remove the definition of listfunc and just use golistPackages once go1.12 is released. + var listfunc driver + listfunc = func(cfg *Config, words ...string) (*driverResponse, error) { + response, err := golistDriverCurrent(cfg, words...) + if _, ok := err.(goTooOldError); ok { + listfunc = golistDriverFallback + return listfunc(cfg, words...) + } + listfunc = golistDriverCurrent + return response, err + } + + var response *driverResponse + var err error + + // see if we have any patterns to pass through to go list. + if len(restPatterns) > 0 { + response, err = listfunc(cfg, restPatterns...) + if err != nil { + return nil, err + } + } else { + response = &driverResponse{} + } + + if len(containFiles) == 0 && len(packagesNamed) == 0 { + return response, nil + } + + seenPkgs := make(map[string]*Package) // for deduplication. different containing queries could produce same packages + for _, pkg := range response.Packages { + seenPkgs[pkg.ID] = pkg + } + addPkg := func(p *Package) { + if _, ok := seenPkgs[p.ID]; ok { + return + } + seenPkgs[p.ID] = p + response.Packages = append(response.Packages, p) + } + + containsResults, err := runContainsQueries(cfg, listfunc, addPkg, containFiles) + if err != nil { + return nil, err + } + response.Roots = append(response.Roots, containsResults...) + + namedResults, err := runNamedQueries(cfg, listfunc, addPkg, packagesNamed) + if err != nil { + return nil, err + } + response.Roots = append(response.Roots, namedResults...) + + return response, nil +} + +func runContainsQueries(cfg *Config, driver driver, addPkg func(*Package), queries []string) ([]string, error) { + var results []string + for _, query := range queries { + // TODO(matloob): Do only one query per directory. + fdir := filepath.Dir(query) + cfg.Dir = fdir + dirResponse, err := driver(cfg, ".") + if err != nil { + return nil, err + } + isRoot := make(map[string]bool, len(dirResponse.Roots)) + for _, root := range dirResponse.Roots { + isRoot[root] = true + } + for _, pkg := range dirResponse.Packages { + // Add any new packages to the main set + // We don't bother to filter packages that will be dropped by the changes of roots, + // that will happen anyway during graph construction outside this function. + // Over-reporting packages is not a problem. + addPkg(pkg) + // if the package was not a root one, it cannot have the file + if !isRoot[pkg.ID] { + continue + } + for _, pkgFile := range pkg.GoFiles { + if filepath.Base(query) == filepath.Base(pkgFile) { + results = append(results, pkg.ID) + break + } + } + } + } + return results, nil +} + +// modCacheRegexp splits a path in a module cache into module, module version, and package. +var modCacheRegexp = regexp.MustCompile(`(.*)@([^/\\]*)(.*)`) + +func runNamedQueries(cfg *Config, driver driver, addPkg func(*Package), queries []string) ([]string, error) { + // Determine which directories are relevant to scan. + roots, modulesEnabled, err := roots(cfg) + if err != nil { + return nil, err + } + + // Scan the selected directories. Simple matches, from GOPATH/GOROOT + // or the local module, can simply be "go list"ed. Matches from the + // module cache need special treatment. + var matchesMu sync.Mutex + var simpleMatches, modCacheMatches []string + add := func(root gopathwalk.Root, dir string) { + // Walk calls this concurrently; protect the result slices. + matchesMu.Lock() + defer matchesMu.Unlock() + + path := dir[len(root.Path)+1:] + if pathMatchesQueries(path, queries) { + switch root.Type { + case gopathwalk.RootModuleCache: + modCacheMatches = append(modCacheMatches, path) + case gopathwalk.RootCurrentModule: + // We'd need to read go.mod to find the full + // import path. Relative's easier. + rel, err := filepath.Rel(cfg.Dir, dir) + if err != nil { + // This ought to be impossible, since + // we found dir in the current module. + panic(err) + } + simpleMatches = append(simpleMatches, "./"+rel) + case gopathwalk.RootGOPATH, gopathwalk.RootGOROOT: + simpleMatches = append(simpleMatches, path) + } + } + } + gopathwalk.Walk(roots, add, gopathwalk.Options{ModulesEnabled: modulesEnabled}) + + var results []string + addResponse := func(r *driverResponse) { + for _, pkg := range r.Packages { + addPkg(pkg) + for _, name := range queries { + if pkg.Name == name { + results = append(results, pkg.ID) + break + } + } + } + } + + if len(simpleMatches) != 0 { + resp, err := driver(cfg, simpleMatches...) + if err != nil { + return nil, err + } + addResponse(resp) + } + + // Module cache matches are tricky. We want to avoid downloading new + // versions of things, so we need to use the ones present in the cache. + // go list doesn't accept version specifiers, so we have to write out a + // temporary module, and do the list in that module. + if len(modCacheMatches) != 0 { + // Collect all the matches, deduplicating by major version + // and preferring the newest. + type modInfo struct { + mod string + major string + } + mods := make(map[modInfo]string) + var imports []string + for _, modPath := range modCacheMatches { + matches := modCacheRegexp.FindStringSubmatch(modPath) + mod, ver := filepath.ToSlash(matches[1]), matches[2] + importPath := filepath.ToSlash(filepath.Join(matches[1], matches[3])) + + major := semver.Major(ver) + if prevVer, ok := mods[modInfo{mod, major}]; !ok || semver.Compare(ver, prevVer) > 0 { + mods[modInfo{mod, major}] = ver + } + + imports = append(imports, importPath) + } + + // Build the temporary module. + var gomod bytes.Buffer + gomod.WriteString("module modquery\nrequire (\n") + for mod, version := range mods { + gomod.WriteString("\t" + mod.mod + " " + version + "\n") + } + gomod.WriteString(")\n") + + tmpCfg := *cfg + var err error + tmpCfg.Dir, err = ioutil.TempDir("", "gopackages-modquery") + if err != nil { + return nil, err + } + defer os.RemoveAll(tmpCfg.Dir) + + if err := ioutil.WriteFile(filepath.Join(tmpCfg.Dir, "go.mod"), gomod.Bytes(), 0777); err != nil { + return nil, fmt.Errorf("writing go.mod for module cache query: %v", err) + } + + // Run the query, using the import paths calculated from the matches above. + resp, err := driver(&tmpCfg, imports...) + if err != nil { + return nil, fmt.Errorf("querying module cache matches: %v", err) + } + addResponse(resp) + } + + return results, nil +} + +// roots selects the appropriate paths to walk based on the passed-in configuration, +// particularly the environment and the presence of a go.mod in cfg.Dir's parents. +func roots(cfg *Config) ([]gopathwalk.Root, bool, error) { + stdout, err := invokeGo(cfg, "env", "GOROOT", "GOPATH", "GOMOD") + if err != nil { + return nil, false, err + } + + fields := strings.Split(stdout.String(), "\n") + if len(fields) != 4 || len(fields[3]) != 0 { + return nil, false, fmt.Errorf("go env returned unexpected output: %q", stdout.String()) + } + goroot, gopath, gomod := fields[0], filepath.SplitList(fields[1]), fields[2] + modsEnabled := gomod != "" + + var roots []gopathwalk.Root + // Always add GOROOT. + roots = append(roots, gopathwalk.Root{filepath.Join(goroot, "/src"), gopathwalk.RootGOROOT}) + // If modules are enabled, scan the module dir. + if modsEnabled { + roots = append(roots, gopathwalk.Root{filepath.Dir(gomod), gopathwalk.RootCurrentModule}) + } + // Add either GOPATH/src or GOPATH/pkg/mod, depending on module mode. + for _, p := range gopath { + if modsEnabled { + roots = append(roots, gopathwalk.Root{filepath.Join(p, "/pkg/mod"), gopathwalk.RootModuleCache}) + } else { + roots = append(roots, gopathwalk.Root{filepath.Join(p, "/src"), gopathwalk.RootGOPATH}) + } + } + + return roots, modsEnabled, nil +} + +// These functions were copied from goimports. See further documentation there. + +// pathMatchesQueries is adapted from pkgIsCandidate. +// TODO: is it reasonable to do Contains here, rather than an exact match on a path component? +func pathMatchesQueries(path string, queries []string) bool { + lastTwo := lastTwoComponents(path) + for _, query := range queries { + if strings.Contains(lastTwo, query) { + return true + } + if hasHyphenOrUpperASCII(lastTwo) && !hasHyphenOrUpperASCII(query) { + lastTwo = lowerASCIIAndRemoveHyphen(lastTwo) + if strings.Contains(lastTwo, query) { + return true + } + } + } + return false +} + +// lastTwoComponents returns at most the last two path components +// of v, using either / or \ as the path separator. +func lastTwoComponents(v string) string { + nslash := 0 + for i := len(v) - 1; i >= 0; i-- { + if v[i] == '/' || v[i] == '\\' { + nslash++ + if nslash == 2 { + return v[i:] + } + } + } + return v +} + +func hasHyphenOrUpperASCII(s string) bool { + for i := 0; i < len(s); i++ { + b := s[i] + if b == '-' || ('A' <= b && b <= 'Z') { + return true + } + } + return false +} + +func lowerASCIIAndRemoveHyphen(s string) (ret string) { + buf := make([]byte, 0, len(s)) + for i := 0; i < len(s); i++ { + b := s[i] + switch { + case b == '-': + continue + case 'A' <= b && b <= 'Z': + buf = append(buf, b+('a'-'A')) + default: + buf = append(buf, b) + } + } + return string(buf) +} + +// Fields must match go list; +// see $GOROOT/src/cmd/go/internal/load/pkg.go. +type jsonPackage struct { + ImportPath string + Dir string + Name string + Export string + GoFiles []string + CompiledGoFiles []string + CFiles []string + CgoFiles []string + CXXFiles []string + MFiles []string + HFiles []string + FFiles []string + SFiles []string + SwigFiles []string + SwigCXXFiles []string + SysoFiles []string + Imports []string + ImportMap map[string]string + Deps []string + TestGoFiles []string + TestImports []string + XTestGoFiles []string + XTestImports []string + ForTest string // q in a "p [q.test]" package, else "" + DepOnly bool + + Error *jsonPackageError +} + +type jsonPackageError struct { + ImportStack []string + Pos string + Err string +} + +func otherFiles(p *jsonPackage) [][]string { + return [][]string{p.CFiles, p.CXXFiles, p.MFiles, p.HFiles, p.FFiles, p.SFiles, p.SwigFiles, p.SwigCXXFiles, p.SysoFiles} +} + +// golistDriverCurrent uses the "go list" command to expand the +// pattern words and return metadata for the specified packages. +// dir may be "" and env may be nil, as per os/exec.Command. +func golistDriverCurrent(cfg *Config, words ...string) (*driverResponse, error) { + // go list uses the following identifiers in ImportPath and Imports: + // + // "p" -- importable package or main (command) + // "q.test" -- q's test executable + // "p [q.test]" -- variant of p as built for q's test executable + // "q_test [q.test]" -- q's external test package + // + // The packages p that are built differently for a test q.test + // are q itself, plus any helpers used by the external test q_test, + // typically including "testing" and all its dependencies. + + // Run "go list" for complete + // information on the specified packages. + buf, err := invokeGo(cfg, golistargs(cfg, words)...) + if err != nil { + return nil, err + } + // Decode the JSON and convert it to Package form. + var response driverResponse + for dec := json.NewDecoder(buf); dec.More(); { + p := new(jsonPackage) + if err := dec.Decode(p); err != nil { + return nil, fmt.Errorf("JSON decoding failed: %v", err) + } + + if p.ImportPath == "" { + // The documentation for go list says that “[e]rroneous packages will have + // a non-empty ImportPath”. If for some reason it comes back empty, we + // prefer to error out rather than silently discarding data or handing + // back a package without any way to refer to it. + if p.Error != nil { + return nil, Error{ + Pos: p.Error.Pos, + Msg: p.Error.Err, + } + } + return nil, fmt.Errorf("package missing import path: %+v", p) + } + + pkg := &Package{ + Name: p.Name, + ID: p.ImportPath, + GoFiles: absJoin(p.Dir, p.GoFiles, p.CgoFiles), + CompiledGoFiles: absJoin(p.Dir, p.CompiledGoFiles), + OtherFiles: absJoin(p.Dir, otherFiles(p)...), + } + + // Extract the PkgPath from the package's ID. + if i := strings.IndexByte(pkg.ID, ' '); i >= 0 { + pkg.PkgPath = pkg.ID[:i] + } else { + pkg.PkgPath = pkg.ID + } + + if pkg.PkgPath == "unsafe" { + pkg.GoFiles = nil // ignore fake unsafe.go file + } + + // Assume go list emits only absolute paths for Dir. + if p.Dir != "" && !filepath.IsAbs(p.Dir) { + log.Fatalf("internal error: go list returned non-absolute Package.Dir: %s", p.Dir) + } + + if p.Export != "" && !filepath.IsAbs(p.Export) { + pkg.ExportFile = filepath.Join(p.Dir, p.Export) + } else { + pkg.ExportFile = p.Export + } + + // imports + // + // Imports contains the IDs of all imported packages. + // ImportsMap records (path, ID) only where they differ. + ids := make(map[string]bool) + for _, id := range p.Imports { + ids[id] = true + } + pkg.Imports = make(map[string]*Package) + for path, id := range p.ImportMap { + pkg.Imports[path] = &Package{ID: id} // non-identity import + delete(ids, id) + } + for id := range ids { + if id == "C" { + continue + } + + pkg.Imports[id] = &Package{ID: id} // identity import + } + if !p.DepOnly { + response.Roots = append(response.Roots, pkg.ID) + } + + // TODO(matloob): Temporary hack since CompiledGoFiles isn't always set. + if len(pkg.CompiledGoFiles) == 0 { + pkg.CompiledGoFiles = pkg.GoFiles + } + + if p.Error != nil { + pkg.Errors = append(pkg.Errors, Error{ + Pos: p.Error.Pos, + Msg: p.Error.Err, + }) + } + + response.Packages = append(response.Packages, pkg) + } + + return &response, nil +} + +// absJoin absolutizes and flattens the lists of files. +func absJoin(dir string, fileses ...[]string) (res []string) { + for _, files := range fileses { + for _, file := range files { + if !filepath.IsAbs(file) { + file = filepath.Join(dir, file) + } + res = append(res, file) + } + } + return res +} + +func golistargs(cfg *Config, words []string) []string { + fullargs := []string{ + "list", "-e", "-json", "-compiled", + fmt.Sprintf("-test=%t", cfg.Tests), + fmt.Sprintf("-export=%t", usesExportData(cfg)), + fmt.Sprintf("-deps=%t", cfg.Mode >= LoadImports), + } + fullargs = append(fullargs, cfg.BuildFlags...) + fullargs = append(fullargs, "--") + fullargs = append(fullargs, words...) + return fullargs +} + +// invokeGo returns the stdout of a go command invocation. +func invokeGo(cfg *Config, args ...string) (*bytes.Buffer, error) { + stdout := new(bytes.Buffer) + stderr := new(bytes.Buffer) + cmd := exec.CommandContext(cfg.Context, "go", args...) + // On darwin the cwd gets resolved to the real path, which breaks anything that + // expects the working directory to keep the original path, including the + // go command when dealing with modules. + // The Go stdlib has a special feature where if the cwd and the PWD are the + // same node then it trusts the PWD, so by setting it in the env for the child + // process we fix up all the paths returned by the go command. + cmd.Env = append(append([]string{}, cfg.Env...), "PWD="+cfg.Dir) + cmd.Dir = cfg.Dir + cmd.Stdout = stdout + cmd.Stderr = stderr + if err := cmd.Run(); err != nil { + exitErr, ok := err.(*exec.ExitError) + if !ok { + // Catastrophic error: + // - executable not found + // - context cancellation + return nil, fmt.Errorf("couldn't exec 'go %v': %s %T", args, err, err) + } + + // Old go version? + if strings.Contains(stderr.String(), "flag provided but not defined") { + return nil, goTooOldError{fmt.Errorf("unsupported version of go: %s: %s", exitErr, stderr)} + } + + // Export mode entails a build. + // If that build fails, errors appear on stderr + // (despite the -e flag) and the Export field is blank. + // Do not fail in that case. + if !usesExportData(cfg) { + return nil, fmt.Errorf("go %v: %s: %s", args, exitErr, stderr) + } + } + + // As of writing, go list -export prints some non-fatal compilation + // errors to stderr, even with -e set. We would prefer that it put + // them in the Package.Error JSON (see http://golang.org/issue/26319). + // In the meantime, there's nowhere good to put them, but they can + // be useful for debugging. Print them if $GOPACKAGESPRINTGOLISTERRORS + // is set. + if len(stderr.Bytes()) != 0 && os.Getenv("GOPACKAGESPRINTGOLISTERRORS") != "" { + fmt.Fprintf(os.Stderr, "go %v stderr: <<%s>>\n", args, stderr) + } + + // debugging + if false { + fmt.Fprintf(os.Stderr, "go %v stdout: <<%s>>\n", args, stdout) + } + + return stdout, nil +} diff --git a/vendor/golang.org/x/tools/go/packages/golist_fallback.go b/vendor/golang.org/x/tools/go/packages/golist_fallback.go new file mode 100644 index 0000000000..ac0c34f014 --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/golist_fallback.go @@ -0,0 +1,457 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package packages + +import ( + "encoding/json" + "fmt" + "go/build" + "io/ioutil" + "os" + "os/exec" + "path/filepath" + "sort" + "strings" + + "golang.org/x/tools/go/internal/cgo" +) + +// TODO(matloob): Delete this file once Go 1.12 is released. + +// This file provides backwards compatibility support for +// loading for versions of Go earlier than 1.10.4. This support is meant to +// assist with migration to the Package API until there's +// widespread adoption of these newer Go versions. +// This support will be removed once Go 1.12 is released +// in Q1 2019. + +func golistDriverFallback(cfg *Config, words ...string) (*driverResponse, error) { + // Turn absolute paths into GOROOT and GOPATH-relative paths to provide to go list. + // This will have surprising behavior if GOROOT or GOPATH contain multiple packages with the same + // path and a user provides an absolute path to a directory that's shadowed by an earlier + // directory in GOROOT or GOPATH with the same package path. + words = cleanAbsPaths(cfg, words) + + original, deps, err := getDeps(cfg, words...) + if err != nil { + return nil, err + } + + var tmpdir string // used for generated cgo files + var needsTestVariant []struct { + pkg, xtestPkg *Package + } + + var response driverResponse + allPkgs := make(map[string]bool) + addPackage := func(p *jsonPackage) { + id := p.ImportPath + + if allPkgs[id] { + return + } + allPkgs[id] = true + + isRoot := original[id] != nil + pkgpath := id + + if pkgpath == "unsafe" { + p.GoFiles = nil // ignore fake unsafe.go file + } + + importMap := func(importlist []string) map[string]*Package { + importMap := make(map[string]*Package) + for _, id := range importlist { + + if id == "C" { + for _, path := range []string{"unsafe", "syscall", "runtime/cgo"} { + if pkgpath != path && importMap[path] == nil { + importMap[path] = &Package{ID: path} + } + } + continue + } + importMap[vendorlessPath(id)] = &Package{ID: id} + } + return importMap + } + compiledGoFiles := absJoin(p.Dir, p.GoFiles) + // Use a function to simplify control flow. It's just a bunch of gotos. + var cgoErrors []error + var outdir string + getOutdir := func() (string, error) { + if outdir != "" { + return outdir, nil + } + if tmpdir == "" { + if tmpdir, err = ioutil.TempDir("", "gopackages"); err != nil { + return "", err + } + } + // Add a "go-build" component to the path to make the tests think the files are in the cache. + // This allows the same test to test the pre- and post-Go 1.11 go list logic because the Go 1.11 + // go list generates test mains in the cache, and the test code knows not to rely on paths in the + // cache to stay stable. + outdir = filepath.Join(tmpdir, "go-build", strings.Replace(p.ImportPath, "/", "_", -1)) + if err := os.MkdirAll(outdir, 0755); err != nil { + outdir = "" + return "", err + } + return outdir, nil + } + processCgo := func() bool { + // Suppress any cgo errors. Any relevant errors will show up in typechecking. + // TODO(matloob): Skip running cgo if Mode < LoadTypes. + outdir, err := getOutdir() + if err != nil { + cgoErrors = append(cgoErrors, err) + return false + } + files, _, err := runCgo(p.Dir, outdir, cfg.Env) + if err != nil { + cgoErrors = append(cgoErrors, err) + return false + } + compiledGoFiles = append(compiledGoFiles, files...) + return true + } + if len(p.CgoFiles) == 0 || !processCgo() { + compiledGoFiles = append(compiledGoFiles, absJoin(p.Dir, p.CgoFiles)...) // Punt to typechecker. + } + if isRoot { + response.Roots = append(response.Roots, id) + } + pkg := &Package{ + ID: id, + Name: p.Name, + GoFiles: absJoin(p.Dir, p.GoFiles, p.CgoFiles), + CompiledGoFiles: compiledGoFiles, + OtherFiles: absJoin(p.Dir, otherFiles(p)...), + PkgPath: pkgpath, + Imports: importMap(p.Imports), + // TODO(matloob): set errors on the Package to cgoErrors + } + if p.Error != nil { + pkg.Errors = append(pkg.Errors, Error{ + Pos: p.Error.Pos, + Msg: p.Error.Err, + }) + } + response.Packages = append(response.Packages, pkg) + if cfg.Tests && isRoot { + testID := fmt.Sprintf("%s [%s.test]", id, id) + if len(p.TestGoFiles) > 0 || len(p.XTestGoFiles) > 0 { + response.Roots = append(response.Roots, testID) + testPkg := &Package{ + ID: testID, + Name: p.Name, + GoFiles: absJoin(p.Dir, p.GoFiles, p.CgoFiles, p.TestGoFiles), + CompiledGoFiles: append(compiledGoFiles, absJoin(p.Dir, p.TestGoFiles)...), + OtherFiles: absJoin(p.Dir, otherFiles(p)...), + PkgPath: pkgpath, + Imports: importMap(append(p.Imports, p.TestImports...)), + // TODO(matloob): set errors on the Package to cgoErrors + } + response.Packages = append(response.Packages, testPkg) + var xtestPkg *Package + if len(p.XTestGoFiles) > 0 { + xtestID := fmt.Sprintf("%s_test [%s.test]", id, id) + response.Roots = append(response.Roots, xtestID) + // Generate test variants for all packages q where a path exists + // such that xtestPkg -> ... -> q -> ... -> p (where p is the package under test) + // and rewrite all import map entries of p to point to testPkg (the test variant of + // p), and of each q to point to the test variant of that q. + xtestPkg = &Package{ + ID: xtestID, + Name: p.Name + "_test", + GoFiles: absJoin(p.Dir, p.XTestGoFiles), + CompiledGoFiles: absJoin(p.Dir, p.XTestGoFiles), + PkgPath: pkgpath + "_test", + Imports: importMap(p.XTestImports), + } + // Add to list of packages we need to rewrite imports for to refer to test variants. + // We may need to create a test variant of a package that hasn't been loaded yet, so + // the test variants need to be created later. + needsTestVariant = append(needsTestVariant, struct{ pkg, xtestPkg *Package }{pkg, xtestPkg}) + response.Packages = append(response.Packages, xtestPkg) + } + // testmain package + testmainID := id + ".test" + response.Roots = append(response.Roots, testmainID) + imports := map[string]*Package{} + imports[testPkg.PkgPath] = &Package{ID: testPkg.ID} + if xtestPkg != nil { + imports[xtestPkg.PkgPath] = &Package{ID: xtestPkg.ID} + } + testmainPkg := &Package{ + ID: testmainID, + Name: "main", + PkgPath: testmainID, + Imports: imports, + } + response.Packages = append(response.Packages, testmainPkg) + outdir, err := getOutdir() + if err != nil { + testmainPkg.Errors = append(testmainPkg.Errors, Error{ + Pos: "-", + Msg: fmt.Sprintf("failed to generate testmain: %v", err), + Kind: ListError, + }) + return + } + testmain := filepath.Join(outdir, "testmain.go") + extraimports, extradeps, err := generateTestmain(testmain, testPkg, xtestPkg) + if err != nil { + testmainPkg.Errors = append(testmainPkg.Errors, Error{ + Pos: "-", + Msg: fmt.Sprintf("failed to generate testmain: %v", err), + Kind: ListError, + }) + } + deps = append(deps, extradeps...) + for _, imp := range extraimports { // testing, testing/internal/testdeps, and maybe os + imports[imp] = &Package{ID: imp} + } + testmainPkg.GoFiles = []string{testmain} + testmainPkg.CompiledGoFiles = []string{testmain} + } + } + } + + for _, pkg := range original { + addPackage(pkg) + } + if cfg.Mode < LoadImports || len(deps) == 0 { + return &response, nil + } + + buf, err := invokeGo(cfg, golistArgsFallback(cfg, deps)...) + if err != nil { + return nil, err + } + + // Decode the JSON and convert it to Package form. + for dec := json.NewDecoder(buf); dec.More(); { + p := new(jsonPackage) + if err := dec.Decode(p); err != nil { + return nil, fmt.Errorf("JSON decoding failed: %v", err) + } + + addPackage(p) + } + + for _, v := range needsTestVariant { + createTestVariants(&response, v.pkg, v.xtestPkg) + } + + // TODO(matloob): Is this the right ordering? + sort.SliceStable(response.Packages, func(i, j int) bool { + return response.Packages[i].PkgPath < response.Packages[j].PkgPath + }) + + return &response, nil +} + +func createTestVariants(response *driverResponse, pkgUnderTest, xtestPkg *Package) { + allPkgs := make(map[string]*Package) + for _, pkg := range response.Packages { + allPkgs[pkg.ID] = pkg + } + needsTestVariant := make(map[string]bool) + needsTestVariant[pkgUnderTest.ID] = true + var needsVariantRec func(p *Package) bool + needsVariantRec = func(p *Package) bool { + if needsTestVariant[p.ID] { + return true + } + for _, imp := range p.Imports { + if needsVariantRec(allPkgs[imp.ID]) { + // Don't break because we want to make sure all dependencies + // have been processed, and all required test variants of our dependencies + // exist. + needsTestVariant[p.ID] = true + } + } + if !needsTestVariant[p.ID] { + return false + } + // Create a clone of the package. It will share the same strings and lists of source files, + // but that's okay. It's only necessary for the Imports map to have a separate identity. + testVariant := *p + testVariant.ID = fmt.Sprintf("%s [%s.test]", p.ID, pkgUnderTest.ID) + testVariant.Imports = make(map[string]*Package) + for imp, pkg := range p.Imports { + testVariant.Imports[imp] = pkg + if needsTestVariant[pkg.ID] { + testVariant.Imports[imp] = &Package{ID: fmt.Sprintf("%s [%s.test]", pkg.ID, pkgUnderTest.ID)} + } + } + response.Packages = append(response.Packages, &testVariant) + return needsTestVariant[p.ID] + } + // finally, update the xtest package's imports + for imp, pkg := range xtestPkg.Imports { + if allPkgs[pkg.ID] == nil { + fmt.Printf("for %s: package %s doesn't exist\n", xtestPkg.ID, pkg.ID) + } + if needsVariantRec(allPkgs[pkg.ID]) { + xtestPkg.Imports[imp] = &Package{ID: fmt.Sprintf("%s [%s.test]", pkg.ID, pkgUnderTest.ID)} + } + } +} + +// cleanAbsPaths replaces all absolute paths with GOPATH- and GOROOT-relative +// paths. If an absolute path is not GOPATH- or GOROOT- relative, it is left as an +// absolute path so an error can be returned later. +func cleanAbsPaths(cfg *Config, words []string) []string { + var searchpaths []string + var cleaned = make([]string, len(words)) + for i := range cleaned { + cleaned[i] = words[i] + // Ignore relative directory paths (they must already be goroot-relative) and Go source files + // (absolute source files are already allowed for ad-hoc packages). + // TODO(matloob): Can there be non-.go files in ad-hoc packages. + if !filepath.IsAbs(cleaned[i]) || strings.HasSuffix(cleaned[i], ".go") { + continue + } + // otherwise, it's an absolute path. Search GOPATH and GOROOT to find it. + if searchpaths == nil { + cmd := exec.Command("go", "env", "GOPATH", "GOROOT") + cmd.Env = cfg.Env + out, err := cmd.Output() + if err != nil { + searchpaths = []string{} + continue // suppress the error, it will show up again when running go list + } + lines := strings.Split(string(out), "\n") + if len(lines) != 3 || lines[0] == "" || lines[1] == "" || lines[2] != "" { + continue // suppress error + } + // first line is GOPATH + for _, path := range filepath.SplitList(lines[0]) { + searchpaths = append(searchpaths, filepath.Join(path, "src")) + } + // second line is GOROOT + searchpaths = append(searchpaths, filepath.Join(lines[1], "src")) + } + for _, sp := range searchpaths { + if strings.HasPrefix(cleaned[i], sp) { + cleaned[i] = strings.TrimPrefix(cleaned[i], sp) + cleaned[i] = strings.TrimLeft(cleaned[i], string(filepath.Separator)) + } + } + } + return cleaned +} + +// vendorlessPath returns the devendorized version of the import path ipath. +// For example, VendorlessPath("foo/bar/vendor/a/b") returns "a/b". +// Copied from golang.org/x/tools/imports/fix.go. +func vendorlessPath(ipath string) string { + // Devendorize for use in import statement. + if i := strings.LastIndex(ipath, "/vendor/"); i >= 0 { + return ipath[i+len("/vendor/"):] + } + if strings.HasPrefix(ipath, "vendor/") { + return ipath[len("vendor/"):] + } + return ipath +} + +// getDeps runs an initial go list to determine all the dependency packages. +func getDeps(cfg *Config, words ...string) (originalSet map[string]*jsonPackage, deps []string, err error) { + buf, err := invokeGo(cfg, golistArgsFallback(cfg, words)...) + if err != nil { + return nil, nil, err + } + + depsSet := make(map[string]bool) + originalSet = make(map[string]*jsonPackage) + var testImports []string + + // Extract deps from the JSON. + for dec := json.NewDecoder(buf); dec.More(); { + p := new(jsonPackage) + if err := dec.Decode(p); err != nil { + return nil, nil, fmt.Errorf("JSON decoding failed: %v", err) + } + + originalSet[p.ImportPath] = p + for _, dep := range p.Deps { + depsSet[dep] = true + } + if cfg.Tests { + // collect the additional imports of the test packages. + pkgTestImports := append(p.TestImports, p.XTestImports...) + for _, imp := range pkgTestImports { + if depsSet[imp] { + continue + } + depsSet[imp] = true + testImports = append(testImports, imp) + } + } + } + // Get the deps of the packages imported by tests. + if len(testImports) > 0 { + buf, err = invokeGo(cfg, golistArgsFallback(cfg, testImports)...) + if err != nil { + return nil, nil, err + } + // Extract deps from the JSON. + for dec := json.NewDecoder(buf); dec.More(); { + p := new(jsonPackage) + if err := dec.Decode(p); err != nil { + return nil, nil, fmt.Errorf("JSON decoding failed: %v", err) + } + for _, dep := range p.Deps { + depsSet[dep] = true + } + } + } + + for orig := range originalSet { + delete(depsSet, orig) + } + + deps = make([]string, 0, len(depsSet)) + for dep := range depsSet { + deps = append(deps, dep) + } + sort.Strings(deps) // ensure output is deterministic + return originalSet, deps, nil +} + +func golistArgsFallback(cfg *Config, words []string) []string { + fullargs := []string{"list", "-e", "-json"} + fullargs = append(fullargs, cfg.BuildFlags...) + fullargs = append(fullargs, "--") + fullargs = append(fullargs, words...) + return fullargs +} + +func runCgo(pkgdir, tmpdir string, env []string) (files, displayfiles []string, err error) { + // Use go/build to open cgo files and determine the cgo flags, etc, from them. + // This is tricky so it's best to avoid reimplementing as much as we can, and + // we plan to delete this support once Go 1.12 is released anyways. + // TODO(matloob): This isn't completely correct because we're using the Default + // context. Perhaps we should more accurately fill in the context. + bp, err := build.ImportDir(pkgdir, build.ImportMode(0)) + if err != nil { + return nil, nil, err + } + for _, ev := range env { + if v := strings.TrimPrefix(ev, "CGO_CPPFLAGS"); v != ev { + bp.CgoCPPFLAGS = append(bp.CgoCPPFLAGS, strings.Fields(v)...) + } else if v := strings.TrimPrefix(ev, "CGO_CFLAGS"); v != ev { + bp.CgoCFLAGS = append(bp.CgoCFLAGS, strings.Fields(v)...) + } else if v := strings.TrimPrefix(ev, "CGO_CXXFLAGS"); v != ev { + bp.CgoCXXFLAGS = append(bp.CgoCXXFLAGS, strings.Fields(v)...) + } else if v := strings.TrimPrefix(ev, "CGO_LDFLAGS"); v != ev { + bp.CgoLDFLAGS = append(bp.CgoLDFLAGS, strings.Fields(v)...) + } + } + return cgo.Run(bp, pkgdir, tmpdir, true) +} diff --git a/vendor/golang.org/x/tools/go/packages/golist_fallback_testmain.go b/vendor/golang.org/x/tools/go/packages/golist_fallback_testmain.go new file mode 100644 index 0000000000..128e00e25a --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/golist_fallback_testmain.go @@ -0,0 +1,318 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file is largely based on the Go 1.10-era cmd/go/internal/test/test.go +// testmain generation code. + +package packages + +import ( + "errors" + "fmt" + "go/ast" + "go/doc" + "go/parser" + "go/token" + "os" + "sort" + "strings" + "text/template" + "unicode" + "unicode/utf8" +) + +// TODO(matloob): Delete this file once Go 1.12 is released. + +// This file complements golist_fallback.go by providing +// support for generating testmains. + +func generateTestmain(out string, testPkg, xtestPkg *Package) (extraimports, extradeps []string, err error) { + testFuncs, err := loadTestFuncs(testPkg, xtestPkg) + if err != nil { + return nil, nil, err + } + extraimports = []string{"testing", "testing/internal/testdeps"} + if testFuncs.TestMain == nil { + extraimports = append(extraimports, "os") + } + // Transitive dependencies of ("testing", "testing/internal/testdeps"). + // os is part of the transitive closure so it and its transitive dependencies are + // included regardless of whether it's imported in the template below. + extradeps = []string{ + "errors", + "internal/cpu", + "unsafe", + "internal/bytealg", + "internal/race", + "runtime/internal/atomic", + "runtime/internal/sys", + "runtime", + "sync/atomic", + "sync", + "io", + "unicode", + "unicode/utf8", + "bytes", + "math", + "syscall", + "time", + "internal/poll", + "internal/syscall/unix", + "internal/testlog", + "os", + "math/bits", + "strconv", + "reflect", + "fmt", + "sort", + "strings", + "flag", + "runtime/debug", + "context", + "runtime/trace", + "testing", + "bufio", + "regexp/syntax", + "regexp", + "compress/flate", + "encoding/binary", + "hash", + "hash/crc32", + "compress/gzip", + "path/filepath", + "io/ioutil", + "text/tabwriter", + "runtime/pprof", + "testing/internal/testdeps", + } + return extraimports, extradeps, writeTestmain(out, testFuncs) +} + +// The following is adapted from the cmd/go testmain generation code. + +// isTestFunc tells whether fn has the type of a testing function. arg +// specifies the parameter type we look for: B, M or T. +func isTestFunc(fn *ast.FuncDecl, arg string) bool { + if fn.Type.Results != nil && len(fn.Type.Results.List) > 0 || + fn.Type.Params.List == nil || + len(fn.Type.Params.List) != 1 || + len(fn.Type.Params.List[0].Names) > 1 { + return false + } + ptr, ok := fn.Type.Params.List[0].Type.(*ast.StarExpr) + if !ok { + return false + } + // We can't easily check that the type is *testing.M + // because we don't know how testing has been imported, + // but at least check that it's *M or *something.M. + // Same applies for B and T. + if name, ok := ptr.X.(*ast.Ident); ok && name.Name == arg { + return true + } + if sel, ok := ptr.X.(*ast.SelectorExpr); ok && sel.Sel.Name == arg { + return true + } + return false +} + +// isTest tells whether name looks like a test (or benchmark, according to prefix). +// It is a Test (say) if there is a character after Test that is not a lower-case letter. +// We don't want TesticularCancer. +func isTest(name, prefix string) bool { + if !strings.HasPrefix(name, prefix) { + return false + } + if len(name) == len(prefix) { // "Test" is ok + return true + } + rune, _ := utf8.DecodeRuneInString(name[len(prefix):]) + return !unicode.IsLower(rune) +} + +// loadTestFuncs returns the testFuncs describing the tests that will be run. +func loadTestFuncs(ptest, pxtest *Package) (*testFuncs, error) { + t := &testFuncs{ + TestPackage: ptest, + XTestPackage: pxtest, + } + for _, file := range ptest.GoFiles { + if !strings.HasSuffix(file, "_test.go") { + continue + } + if err := t.load(file, "_test", &t.ImportTest, &t.NeedTest); err != nil { + return nil, err + } + } + if pxtest != nil { + for _, file := range pxtest.GoFiles { + if err := t.load(file, "_xtest", &t.ImportXtest, &t.NeedXtest); err != nil { + return nil, err + } + } + } + return t, nil +} + +// writeTestmain writes the _testmain.go file for t to the file named out. +func writeTestmain(out string, t *testFuncs) error { + f, err := os.Create(out) + if err != nil { + return err + } + defer f.Close() + + if err := testmainTmpl.Execute(f, t); err != nil { + return err + } + + return nil +} + +type testFuncs struct { + Tests []testFunc + Benchmarks []testFunc + Examples []testFunc + TestMain *testFunc + TestPackage *Package + XTestPackage *Package + ImportTest bool + NeedTest bool + ImportXtest bool + NeedXtest bool +} + +// Tested returns the name of the package being tested. +func (t *testFuncs) Tested() string { + return t.TestPackage.Name +} + +type testFunc struct { + Package string // imported package name (_test or _xtest) + Name string // function name + Output string // output, for examples + Unordered bool // output is allowed to be unordered. +} + +func (t *testFuncs) load(filename, pkg string, doImport, seen *bool) error { + var fset = token.NewFileSet() + + f, err := parser.ParseFile(fset, filename, nil, parser.ParseComments) + if err != nil { + return errors.New("failed to parse test file " + filename) + } + for _, d := range f.Decls { + n, ok := d.(*ast.FuncDecl) + if !ok { + continue + } + if n.Recv != nil { + continue + } + name := n.Name.String() + switch { + case name == "TestMain": + if isTestFunc(n, "T") { + t.Tests = append(t.Tests, testFunc{pkg, name, "", false}) + *doImport, *seen = true, true + continue + } + err := checkTestFunc(fset, n, "M") + if err != nil { + return err + } + if t.TestMain != nil { + return errors.New("multiple definitions of TestMain") + } + t.TestMain = &testFunc{pkg, name, "", false} + *doImport, *seen = true, true + case isTest(name, "Test"): + err := checkTestFunc(fset, n, "T") + if err != nil { + return err + } + t.Tests = append(t.Tests, testFunc{pkg, name, "", false}) + *doImport, *seen = true, true + case isTest(name, "Benchmark"): + err := checkTestFunc(fset, n, "B") + if err != nil { + return err + } + t.Benchmarks = append(t.Benchmarks, testFunc{pkg, name, "", false}) + *doImport, *seen = true, true + } + } + ex := doc.Examples(f) + sort.Slice(ex, func(i, j int) bool { return ex[i].Order < ex[j].Order }) + for _, e := range ex { + *doImport = true // import test file whether executed or not + if e.Output == "" && !e.EmptyOutput { + // Don't run examples with no output. + continue + } + t.Examples = append(t.Examples, testFunc{pkg, "Example" + e.Name, e.Output, e.Unordered}) + *seen = true + } + return nil +} + +func checkTestFunc(fset *token.FileSet, fn *ast.FuncDecl, arg string) error { + if !isTestFunc(fn, arg) { + name := fn.Name.String() + pos := fset.Position(fn.Pos()) + return fmt.Errorf("%s: wrong signature for %s, must be: func %s(%s *testing.%s)", pos, name, name, strings.ToLower(arg), arg) + } + return nil +} + +var testmainTmpl = template.Must(template.New("main").Parse(` +package main + +import ( +{{if not .TestMain}} + "os" +{{end}} + "testing" + "testing/internal/testdeps" + +{{if .ImportTest}} + {{if .NeedTest}}_test{{else}}_{{end}} {{.TestPackage.PkgPath | printf "%q"}} +{{end}} +{{if .ImportXtest}} + {{if .NeedXtest}}_xtest{{else}}_{{end}} {{.XTestPackage.PkgPath | printf "%q"}} +{{end}} +) + +var tests = []testing.InternalTest{ +{{range .Tests}} + {"{{.Name}}", {{.Package}}.{{.Name}}}, +{{end}} +} + +var benchmarks = []testing.InternalBenchmark{ +{{range .Benchmarks}} + {"{{.Name}}", {{.Package}}.{{.Name}}}, +{{end}} +} + +var examples = []testing.InternalExample{ +{{range .Examples}} + {"{{.Name}}", {{.Package}}.{{.Name}}, {{.Output | printf "%q"}}, {{.Unordered}}}, +{{end}} +} + +func init() { + testdeps.ImportPath = {{.TestPackage.PkgPath | printf "%q"}} +} + +func main() { + m := testing.MainStart(testdeps.TestDeps{}, tests, benchmarks, examples) +{{with .TestMain}} + {{.Package}}.{{.Name}}(m) +{{else}} + os.Exit(m.Run()) +{{end}} +} + +`)) diff --git a/vendor/golang.org/x/tools/go/packages/packages.go b/vendor/golang.org/x/tools/go/packages/packages.go new file mode 100644 index 0000000000..84a3dbb10c --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/packages.go @@ -0,0 +1,935 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package packages + +// See doc.go for package documentation and implementation notes. + +import ( + "context" + "encoding/json" + "fmt" + "go/ast" + "go/parser" + "go/scanner" + "go/token" + "go/types" + "io/ioutil" + "log" + "os" + "path/filepath" + "runtime" + "strings" + "sync" + + "golang.org/x/tools/go/gcexportdata" +) + +// A LoadMode specifies the amount of detail to return when loading. +// Higher-numbered modes cause Load to return more information, +// but may be slower. Load may return more information than requested. +type LoadMode int + +const ( + // LoadFiles finds the packages and computes their source file lists. + // Package fields: ID, Name, Errors, GoFiles, and OtherFiles. + LoadFiles LoadMode = iota + + // LoadImports adds import information for each package + // and its dependencies. + // Package fields added: Imports. + LoadImports + + // LoadTypes adds type information for package-level + // declarations in the packages matching the patterns. + // Package fields added: Types, Fset, and IllTyped. + // This mode uses type information provided by the build system when + // possible, and may fill in the ExportFile field. + LoadTypes + + // LoadSyntax adds typed syntax trees for the packages matching the patterns. + // Package fields added: Syntax, and TypesInfo, for direct pattern matches only. + LoadSyntax + + // LoadAllSyntax adds typed syntax trees for the packages matching the patterns + // and all dependencies. + // Package fields added: Types, Fset, Illtyped, Syntax, and TypesInfo, + // for all packages in the import graph. + LoadAllSyntax +) + +// An Config specifies details about how packages should be loaded. +// The zero value is a valid configuration. +// Calls to Load do not modify this struct. +type Config struct { + // Mode controls the level of information returned for each package. + Mode LoadMode + + // Context specifies the context for the load operation. + // If the context is cancelled, the loader may stop early + // and return an ErrCancelled error. + // If Context is nil, the load cannot be cancelled. + Context context.Context + + // Dir is the directory in which to run the build system's query tool + // that provides information about the packages. + // If Dir is empty, the tool is run in the current directory. + Dir string + + // Env is the environment to use when invoking the build system's query tool. + // If Env is nil, the current environment is used. + // As in os/exec's Cmd, only the last value in the slice for + // each environment key is used. To specify the setting of only + // a few variables, append to the current environment, as in: + // + // opt.Env = append(os.Environ(), "GOOS=plan9", "GOARCH=386") + // + Env []string + + // BuildFlags is a list of command-line flags to be passed through to + // the build system's query tool. + BuildFlags []string + + // Fset provides source position information for syntax trees and types. + // If Fset is nil, the loader will create a new FileSet. + Fset *token.FileSet + + // ParseFile is called to read and parse each file + // when preparing a package's type-checked syntax tree. + // It must be safe to call ParseFile simultaneously from multiple goroutines. + // If ParseFile is nil, the loader will uses parser.ParseFile. + // + // ParseFile should parse the source from src and use filename only for + // recording position information. + // + // An application may supply a custom implementation of ParseFile + // to change the effective file contents or the behavior of the parser, + // or to modify the syntax tree. For example, selectively eliminating + // unwanted function bodies can significantly accelerate type checking. + ParseFile func(fset *token.FileSet, filename string, src []byte) (*ast.File, error) + + // If Tests is set, the loader includes not just the packages + // matching a particular pattern but also any related test packages, + // including test-only variants of the package and the test executable. + // + // For example, when using the go command, loading "fmt" with Tests=true + // returns four packages, with IDs "fmt" (the standard package), + // "fmt [fmt.test]" (the package as compiled for the test), + // "fmt_test" (the test functions from source files in package fmt_test), + // and "fmt.test" (the test binary). + // + // In build systems with explicit names for tests, + // setting Tests may have no effect. + Tests bool + + // Overlay provides a mapping of absolute file paths to file contents. + // If the file with the given path already exists, the parser will use the + // alternative file contents provided by the map. + // + // The Package.Imports map may not include packages that are imported only + // by the alternative file contents provided by Overlay. This may cause + // type-checking to fail. + Overlay map[string][]byte +} + +// driver is the type for functions that query the build system for the +// packages named by the patterns. +type driver func(cfg *Config, patterns ...string) (*driverResponse, error) + +// driverResponse contains the results for a driver query. +type driverResponse struct { + // Roots is the set of package IDs that make up the root packages. + // We have to encode this separately because when we encode a single package + // we cannot know if it is one of the roots as that requires knowledge of the + // graph it is part of. + Roots []string `json:",omitempty"` + + // Packages is the full set of packages in the graph. + // The packages are not connected into a graph. + // The Imports if populated will be stubs that only have their ID set. + // Imports will be connected and then type and syntax information added in a + // later pass (see refine). + Packages []*Package +} + +// Load loads and returns the Go packages named by the given patterns. +// +// Config specifies loading options; +// nil behaves the same as an empty Config. +// +// Load returns an error if any of the patterns was invalid +// as defined by the underlying build system. +// It may return an empty list of packages without an error, +// for instance for an empty expansion of a valid wildcard. +// Errors associated with a particular package are recorded in the +// corresponding Package's Errors list, and do not cause Load to +// return an error. Clients may need to handle such errors before +// proceeding with further analysis. The PrintErrors function is +// provided for convenient display of all errors. +func Load(cfg *Config, patterns ...string) ([]*Package, error) { + l := newLoader(cfg) + response, err := defaultDriver(&l.Config, patterns...) + if err != nil { + return nil, err + } + return l.refine(response.Roots, response.Packages...) +} + +// defaultDriver is a driver that looks for an external driver binary, and if +// it does not find it falls back to the built in go list driver. +func defaultDriver(cfg *Config, patterns ...string) (*driverResponse, error) { + driver := findExternalDriver(cfg) + if driver == nil { + driver = goListDriver + } + return driver(cfg, patterns...) +} + +// A Package describes a loaded Go package. +type Package struct { + // ID is a unique identifier for a package, + // in a syntax provided by the underlying build system. + // + // Because the syntax varies based on the build system, + // clients should treat IDs as opaque and not attempt to + // interpret them. + ID string + + // Name is the package name as it appears in the package source code. + Name string + + // PkgPath is the package path as used by the go/types package. + PkgPath string + + // Errors contains any errors encountered querying the metadata + // of the package, or while parsing or type-checking its files. + Errors []Error + + // GoFiles lists the absolute file paths of the package's Go source files. + GoFiles []string + + // CompiledGoFiles lists the absolute file paths of the package's source + // files that were presented to the compiler. + // This may differ from GoFiles if files are processed before compilation. + CompiledGoFiles []string + + // OtherFiles lists the absolute file paths of the package's non-Go source files, + // including assembly, C, C++, Fortran, Objective-C, SWIG, and so on. + OtherFiles []string + + // ExportFile is the absolute path to a file containing type + // information for the package as provided by the build system. + ExportFile string + + // Imports maps import paths appearing in the package's Go source files + // to corresponding loaded Packages. + Imports map[string]*Package + + // Types provides type information for the package. + // Modes LoadTypes and above set this field for packages matching the + // patterns; type information for dependencies may be missing or incomplete. + // Mode LoadAllSyntax sets this field for all packages, including dependencies. + Types *types.Package + + // Fset provides position information for Types, TypesInfo, and Syntax. + // It is set only when Types is set. + Fset *token.FileSet + + // IllTyped indicates whether the package or any dependency contains errors. + // It is set only when Types is set. + IllTyped bool + + // Syntax is the package's syntax trees, for the files listed in CompiledGoFiles. + // + // Mode LoadSyntax sets this field for packages matching the patterns. + // Mode LoadAllSyntax sets this field for all packages, including dependencies. + Syntax []*ast.File + + // TypesInfo provides type information about the package's syntax trees. + // It is set only when Syntax is set. + TypesInfo *types.Info +} + +// An Error describes a problem with a package's metadata, syntax, or types. +type Error struct { + Pos string // "file:line:col" or "file:line" or "" or "-" + Msg string + Kind ErrorKind +} + +// ErrorKind describes the source of the error, allowing the user to +// differentiate between errors generated by the driver, the parser, or the +// type-checker. +type ErrorKind int + +const ( + UnknownError ErrorKind = iota + ListError + ParseError + TypeError +) + +func (err Error) Error() string { + pos := err.Pos + if pos == "" { + pos = "-" // like token.Position{}.String() + } + return pos + ": " + err.Msg +} + +// flatPackage is the JSON form of Package +// It drops all the type and syntax fields, and transforms the Imports +// +// TODO(adonovan): identify this struct with Package, effectively +// publishing the JSON protocol. +type flatPackage struct { + ID string + Name string `json:",omitempty"` + PkgPath string `json:",omitempty"` + Errors []Error `json:",omitempty"` + GoFiles []string `json:",omitempty"` + CompiledGoFiles []string `json:",omitempty"` + OtherFiles []string `json:",omitempty"` + ExportFile string `json:",omitempty"` + Imports map[string]string `json:",omitempty"` +} + +// MarshalJSON returns the Package in its JSON form. +// For the most part, the structure fields are written out unmodified, and +// the type and syntax fields are skipped. +// The imports are written out as just a map of path to package id. +// The errors are written using a custom type that tries to preserve the +// structure of error types we know about. +// +// This method exists to enable support for additional build systems. It is +// not intended for use by clients of the API and we may change the format. +func (p *Package) MarshalJSON() ([]byte, error) { + flat := &flatPackage{ + ID: p.ID, + Name: p.Name, + PkgPath: p.PkgPath, + Errors: p.Errors, + GoFiles: p.GoFiles, + CompiledGoFiles: p.CompiledGoFiles, + OtherFiles: p.OtherFiles, + ExportFile: p.ExportFile, + } + if len(p.Imports) > 0 { + flat.Imports = make(map[string]string, len(p.Imports)) + for path, ipkg := range p.Imports { + flat.Imports[path] = ipkg.ID + } + } + return json.Marshal(flat) +} + +// UnmarshalJSON reads in a Package from its JSON format. +// See MarshalJSON for details about the format accepted. +func (p *Package) UnmarshalJSON(b []byte) error { + flat := &flatPackage{} + if err := json.Unmarshal(b, &flat); err != nil { + return err + } + *p = Package{ + ID: flat.ID, + Name: flat.Name, + PkgPath: flat.PkgPath, + Errors: flat.Errors, + GoFiles: flat.GoFiles, + CompiledGoFiles: flat.CompiledGoFiles, + OtherFiles: flat.OtherFiles, + ExportFile: flat.ExportFile, + } + if len(flat.Imports) > 0 { + p.Imports = make(map[string]*Package, len(flat.Imports)) + for path, id := range flat.Imports { + p.Imports[path] = &Package{ID: id} + } + } + return nil +} + +func (p *Package) String() string { return p.ID } + +// loaderPackage augments Package with state used during the loading phase +type loaderPackage struct { + *Package + importErrors map[string]error // maps each bad import to its error + loadOnce sync.Once + color uint8 // for cycle detection + needsrc bool // load from source (Mode >= LoadTypes) + needtypes bool // type information is either requested or depended on + initial bool // package was matched by a pattern +} + +// loader holds the working state of a single call to load. +type loader struct { + pkgs map[string]*loaderPackage + Config + exportMu sync.Mutex // enforces mutual exclusion of exportdata operations +} + +func newLoader(cfg *Config) *loader { + ld := &loader{} + if cfg != nil { + ld.Config = *cfg + } + if ld.Config.Env == nil { + ld.Config.Env = os.Environ() + } + if ld.Context == nil { + ld.Context = context.Background() + } + if ld.Dir == "" { + if dir, err := os.Getwd(); err == nil { + ld.Dir = dir + } + } + + if ld.Mode >= LoadTypes { + if ld.Fset == nil { + ld.Fset = token.NewFileSet() + } + + // ParseFile is required even in LoadTypes mode + // because we load source if export data is missing. + if ld.ParseFile == nil { + ld.ParseFile = func(fset *token.FileSet, filename string, src []byte) (*ast.File, error) { + var isrc interface{} + if src != nil { + isrc = src + } + const mode = parser.AllErrors | parser.ParseComments + return parser.ParseFile(fset, filename, isrc, mode) + } + } + } + return ld +} + +// refine connects the supplied packages into a graph and then adds type and +// and syntax information as requested by the LoadMode. +func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) { + isRoot := make(map[string]bool, len(roots)) + for _, root := range roots { + isRoot[root] = true + } + ld.pkgs = make(map[string]*loaderPackage) + // first pass, fixup and build the map and roots + var initial []*loaderPackage + for _, pkg := range list { + lpkg := &loaderPackage{ + Package: pkg, + needtypes: ld.Mode >= LoadAllSyntax || + ld.Mode >= LoadTypes && isRoot[pkg.ID], + needsrc: ld.Mode >= LoadAllSyntax || + ld.Mode >= LoadSyntax && isRoot[pkg.ID] || + pkg.ExportFile == "" && pkg.PkgPath != "unsafe", + } + ld.pkgs[lpkg.ID] = lpkg + if isRoot[lpkg.ID] { + initial = append(initial, lpkg) + lpkg.initial = true + } + } + + // Materialize the import graph. + + const ( + white = 0 // new + grey = 1 // in progress + black = 2 // complete + ) + + // visit traverses the import graph, depth-first, + // and materializes the graph as Packages.Imports. + // + // Valid imports are saved in the Packages.Import map. + // Invalid imports (cycles and missing nodes) are saved in the importErrors map. + // Thus, even in the presence of both kinds of errors, the Import graph remains a DAG. + // + // visit returns whether the package needs src or has a transitive + // dependency on a package that does. These are the only packages + // for which we load source code. + var stack []*loaderPackage + var visit func(lpkg *loaderPackage) bool + var srcPkgs []*loaderPackage + visit = func(lpkg *loaderPackage) bool { + switch lpkg.color { + case black: + return lpkg.needsrc + case grey: + panic("internal error: grey node") + } + lpkg.color = grey + stack = append(stack, lpkg) // push + stubs := lpkg.Imports // the structure form has only stubs with the ID in the Imports + lpkg.Imports = make(map[string]*Package, len(stubs)) + for importPath, ipkg := range stubs { + var importErr error + imp := ld.pkgs[ipkg.ID] + if imp == nil { + // (includes package "C" when DisableCgo) + importErr = fmt.Errorf("missing package: %q", ipkg.ID) + } else if imp.color == grey { + importErr = fmt.Errorf("import cycle: %s", stack) + } + if importErr != nil { + if lpkg.importErrors == nil { + lpkg.importErrors = make(map[string]error) + } + lpkg.importErrors[importPath] = importErr + continue + } + + if visit(imp) { + lpkg.needsrc = true + } + lpkg.Imports[importPath] = imp.Package + } + if lpkg.needsrc { + srcPkgs = append(srcPkgs, lpkg) + } + stack = stack[:len(stack)-1] // pop + lpkg.color = black + + return lpkg.needsrc + } + + if ld.Mode < LoadImports { + //we do this to drop the stub import packages that we are not even going to try to resolve + for _, lpkg := range initial { + lpkg.Imports = nil + } + } else { + // For each initial package, create its import DAG. + for _, lpkg := range initial { + visit(lpkg) + } + } + for _, lpkg := range srcPkgs { + // Complete type information is required for the + // immediate dependencies of each source package. + for _, ipkg := range lpkg.Imports { + imp := ld.pkgs[ipkg.ID] + imp.needtypes = true + } + } + // Load type data if needed, starting at + // the initial packages (roots of the import DAG). + if ld.Mode >= LoadTypes { + var wg sync.WaitGroup + for _, lpkg := range initial { + wg.Add(1) + go func(lpkg *loaderPackage) { + ld.loadRecursive(lpkg) + wg.Done() + }(lpkg) + } + wg.Wait() + } + + result := make([]*Package, len(initial)) + for i, lpkg := range initial { + result[i] = lpkg.Package + } + return result, nil +} + +// loadRecursive loads the specified package and its dependencies, +// recursively, in parallel, in topological order. +// It is atomic and idempotent. +// Precondition: ld.Mode >= LoadTypes. +func (ld *loader) loadRecursive(lpkg *loaderPackage) { + lpkg.loadOnce.Do(func() { + // Load the direct dependencies, in parallel. + var wg sync.WaitGroup + for _, ipkg := range lpkg.Imports { + imp := ld.pkgs[ipkg.ID] + wg.Add(1) + go func(imp *loaderPackage) { + ld.loadRecursive(imp) + wg.Done() + }(imp) + } + wg.Wait() + + ld.loadPackage(lpkg) + }) +} + +// loadPackage loads the specified package. +// It must be called only once per Package, +// after immediate dependencies are loaded. +// Precondition: ld.Mode >= LoadTypes. +func (ld *loader) loadPackage(lpkg *loaderPackage) { + if lpkg.PkgPath == "unsafe" { + // Fill in the blanks to avoid surprises. + lpkg.Types = types.Unsafe + lpkg.Fset = ld.Fset + lpkg.Syntax = []*ast.File{} + lpkg.TypesInfo = new(types.Info) + return + } + + // Call NewPackage directly with explicit name. + // This avoids skew between golist and go/types when the files' + // package declarations are inconsistent. + lpkg.Types = types.NewPackage(lpkg.PkgPath, lpkg.Name) + lpkg.Fset = ld.Fset + + // Subtle: we populate all Types fields with an empty Package + // before loading export data so that export data processing + // never has to create a types.Package for an indirect dependency, + // which would then require that such created packages be explicitly + // inserted back into the Import graph as a final step after export data loading. + // The Diamond test exercises this case. + if !lpkg.needtypes { + return + } + if !lpkg.needsrc { + ld.loadFromExportData(lpkg) + return // not a source package, don't get syntax trees + } + + appendError := func(err error) { + // Convert various error types into the one true Error. + var errs []Error + switch err := err.(type) { + case Error: + // from driver + errs = append(errs, err) + + case *os.PathError: + // from parser + errs = append(errs, Error{ + Pos: err.Path + ":1", + Msg: err.Err.Error(), + Kind: ParseError, + }) + + case scanner.ErrorList: + // from parser + for _, err := range err { + errs = append(errs, Error{ + Pos: err.Pos.String(), + Msg: err.Msg, + Kind: ParseError, + }) + } + + case types.Error: + // from type checker + errs = append(errs, Error{ + Pos: err.Fset.Position(err.Pos).String(), + Msg: err.Msg, + Kind: TypeError, + }) + + default: + // unexpected impoverished error from parser? + errs = append(errs, Error{ + Pos: "-", + Msg: err.Error(), + Kind: UnknownError, + }) + + // If you see this error message, please file a bug. + log.Printf("internal error: error %q (%T) without position", err, err) + } + + lpkg.Errors = append(lpkg.Errors, errs...) + } + + files, errs := ld.parseFiles(lpkg.CompiledGoFiles) + for _, err := range errs { + appendError(err) + } + + lpkg.Syntax = files + + lpkg.TypesInfo = &types.Info{ + Types: make(map[ast.Expr]types.TypeAndValue), + Defs: make(map[*ast.Ident]types.Object), + Uses: make(map[*ast.Ident]types.Object), + Implicits: make(map[ast.Node]types.Object), + Scopes: make(map[ast.Node]*types.Scope), + Selections: make(map[*ast.SelectorExpr]*types.Selection), + } + + importer := importerFunc(func(path string) (*types.Package, error) { + if path == "unsafe" { + return types.Unsafe, nil + } + + // The imports map is keyed by import path. + ipkg := lpkg.Imports[path] + if ipkg == nil { + if err := lpkg.importErrors[path]; err != nil { + return nil, err + } + // There was skew between the metadata and the + // import declarations, likely due to an edit + // race, or because the ParseFile feature was + // used to supply alternative file contents. + return nil, fmt.Errorf("no metadata for %s", path) + } + + if ipkg.Types != nil && ipkg.Types.Complete() { + return ipkg.Types, nil + } + log.Fatalf("internal error: nil Pkg importing %q from %q", path, lpkg) + panic("unreachable") + }) + + // This is only an approximation. + // TODO(adonovan): derive Sizes from the underlying build system. + goarch := runtime.GOARCH + const goarchPrefix = "GOARCH=" + for _, e := range ld.Config.Env { + if strings.HasPrefix(e, goarchPrefix) { + goarch = e[len(goarchPrefix):] + } + } + sizes := types.SizesFor("gc", goarch) + + // type-check + tc := &types.Config{ + Importer: importer, + + // Type-check bodies of functions only in non-initial packages. + // Example: for import graph A->B->C and initial packages {A,C}, + // we can ignore function bodies in B. + IgnoreFuncBodies: ld.Mode < LoadAllSyntax && !lpkg.initial, + + Error: appendError, + Sizes: sizes, + } + types.NewChecker(tc, ld.Fset, lpkg.Types, lpkg.TypesInfo).Files(lpkg.Syntax) + + lpkg.importErrors = nil // no longer needed + + // If !Cgo, the type-checker uses FakeImportC mode, so + // it doesn't invoke the importer for import "C", + // nor report an error for the import, + // or for any undefined C.f reference. + // We must detect this explicitly and correctly + // mark the package as IllTyped (by reporting an error). + // TODO(adonovan): if these errors are annoying, + // we could just set IllTyped quietly. + if tc.FakeImportC { + outer: + for _, f := range lpkg.Syntax { + for _, imp := range f.Imports { + if imp.Path.Value == `"C"` { + err := types.Error{Fset: ld.Fset, Pos: imp.Pos(), Msg: `import "C" ignored`} + appendError(err) + break outer + } + } + } + } + + // Record accumulated errors. + illTyped := len(lpkg.Errors) > 0 + if !illTyped { + for _, imp := range lpkg.Imports { + if imp.IllTyped { + illTyped = true + break + } + } + } + lpkg.IllTyped = illTyped +} + +// An importFunc is an implementation of the single-method +// types.Importer interface based on a function value. +type importerFunc func(path string) (*types.Package, error) + +func (f importerFunc) Import(path string) (*types.Package, error) { return f(path) } + +// We use a counting semaphore to limit +// the number of parallel I/O calls per process. +var ioLimit = make(chan bool, 20) + +// parseFiles reads and parses the Go source files and returns the ASTs +// of the ones that could be at least partially parsed, along with a +// list of I/O and parse errors encountered. +// +// Because files are scanned in parallel, the token.Pos +// positions of the resulting ast.Files are not ordered. +// +func (ld *loader) parseFiles(filenames []string) ([]*ast.File, []error) { + var wg sync.WaitGroup + n := len(filenames) + parsed := make([]*ast.File, n) + errors := make([]error, n) + for i, file := range filenames { + wg.Add(1) + go func(i int, filename string) { + ioLimit <- true // wait + // ParseFile may return both an AST and an error. + var src []byte + for f, contents := range ld.Config.Overlay { + if sameFile(f, filename) { + src = contents + } + } + var err error + if src == nil { + src, err = ioutil.ReadFile(filename) + } + if err != nil { + parsed[i], errors[i] = nil, err + } else { + parsed[i], errors[i] = ld.ParseFile(ld.Fset, filename, src) + } + <-ioLimit // signal + wg.Done() + }(i, file) + } + wg.Wait() + + // Eliminate nils, preserving order. + var o int + for _, f := range parsed { + if f != nil { + parsed[o] = f + o++ + } + } + parsed = parsed[:o] + + o = 0 + for _, err := range errors { + if err != nil { + errors[o] = err + o++ + } + } + errors = errors[:o] + + return parsed, errors +} + +// sameFile returns true if x and y have the same basename and denote +// the same file. +// +func sameFile(x, y string) bool { + if filepath.Base(x) == filepath.Base(y) { // (optimisation) + if xi, err := os.Stat(x); err == nil { + if yi, err := os.Stat(y); err == nil { + return os.SameFile(xi, yi) + } + } + } + return false +} + +// loadFromExportData returns type information for the specified +// package, loading it from an export data file on the first request. +func (ld *loader) loadFromExportData(lpkg *loaderPackage) (*types.Package, error) { + if lpkg.PkgPath == "" { + log.Fatalf("internal error: Package %s has no PkgPath", lpkg) + } + + // Because gcexportdata.Read has the potential to create or + // modify the types.Package for each node in the transitive + // closure of dependencies of lpkg, all exportdata operations + // must be sequential. (Finer-grained locking would require + // changes to the gcexportdata API.) + // + // The exportMu lock guards the Package.Pkg field and the + // types.Package it points to, for each Package in the graph. + // + // Not all accesses to Package.Pkg need to be protected by exportMu: + // graph ordering ensures that direct dependencies of source + // packages are fully loaded before the importer reads their Pkg field. + ld.exportMu.Lock() + defer ld.exportMu.Unlock() + + if tpkg := lpkg.Types; tpkg != nil && tpkg.Complete() { + return tpkg, nil // cache hit + } + + lpkg.IllTyped = true // fail safe + + if lpkg.ExportFile == "" { + // Errors while building export data will have been printed to stderr. + return nil, fmt.Errorf("no export data file") + } + f, err := os.Open(lpkg.ExportFile) + if err != nil { + return nil, err + } + defer f.Close() + + // Read gc export data. + // + // We don't currently support gccgo export data because all + // underlying workspaces use the gc toolchain. (Even build + // systems that support gccgo don't use it for workspace + // queries.) + r, err := gcexportdata.NewReader(f) + if err != nil { + return nil, fmt.Errorf("reading %s: %v", lpkg.ExportFile, err) + } + + // Build the view. + // + // The gcexportdata machinery has no concept of package ID. + // It identifies packages by their PkgPath, which although not + // globally unique is unique within the scope of one invocation + // of the linker, type-checker, or gcexportdata. + // + // So, we must build a PkgPath-keyed view of the global + // (conceptually ID-keyed) cache of packages and pass it to + // gcexportdata. The view must contain every existing + // package that might possibly be mentioned by the + // current package---its transitive closure. + // + // In loadPackage, we unconditionally create a types.Package for + // each dependency so that export data loading does not + // create new ones. + // + // TODO(adonovan): it would be simpler and more efficient + // if the export data machinery invoked a callback to + // get-or-create a package instead of a map. + // + view := make(map[string]*types.Package) // view seen by gcexportdata + seen := make(map[*loaderPackage]bool) // all visited packages + var visit func(pkgs map[string]*Package) + visit = func(pkgs map[string]*Package) { + for _, p := range pkgs { + lpkg := ld.pkgs[p.ID] + if !seen[lpkg] { + seen[lpkg] = true + view[lpkg.PkgPath] = lpkg.Types + visit(lpkg.Imports) + } + } + } + visit(lpkg.Imports) + + viewLen := len(view) + 1 // adding the self package + // Parse the export data. + // (May modify incomplete packages in view but not create new ones.) + tpkg, err := gcexportdata.Read(r, ld.Fset, view, lpkg.PkgPath) + if err != nil { + return nil, fmt.Errorf("reading %s: %v", lpkg.ExportFile, err) + } + if viewLen != len(view) { + log.Fatalf("Unexpected package creation during export data loading") + } + + lpkg.Types = tpkg + lpkg.IllTyped = false + + return tpkg, nil +} + +func usesExportData(cfg *Config) bool { + return LoadTypes <= cfg.Mode && cfg.Mode < LoadAllSyntax +} diff --git a/vendor/golang.org/x/tools/go/packages/visit.go b/vendor/golang.org/x/tools/go/packages/visit.go new file mode 100644 index 0000000000..c1a4b28ca0 --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/visit.go @@ -0,0 +1,55 @@ +package packages + +import ( + "fmt" + "os" + "sort" +) + +// Visit visits all the packages in the import graph whose roots are +// pkgs, calling the optional pre function the first time each package +// is encountered (preorder), and the optional post function after a +// package's dependencies have been visited (postorder). +// The boolean result of pre(pkg) determines whether +// the imports of package pkg are visited. +func Visit(pkgs []*Package, pre func(*Package) bool, post func(*Package)) { + seen := make(map[*Package]bool) + var visit func(*Package) + visit = func(pkg *Package) { + if !seen[pkg] { + seen[pkg] = true + + if pre == nil || pre(pkg) { + paths := make([]string, 0, len(pkg.Imports)) + for path := range pkg.Imports { + paths = append(paths, path) + } + sort.Strings(paths) // for determinism + for _, path := range paths { + visit(pkg.Imports[path]) + } + } + + if post != nil { + post(pkg) + } + } + } + for _, pkg := range pkgs { + visit(pkg) + } +} + +// PrintErrors prints to os.Stderr the accumulated errors of all +// packages in the import graph rooted at pkgs, dependencies first. +// PrintErrors returns the number of errors printed. +func PrintErrors(pkgs []*Package) int { + var n int + Visit(pkgs, nil, func(pkg *Package) { + for _, err := range pkg.Errors { + fmt.Fprintln(os.Stderr, err) + n++ + } + }) + return n +} diff --git a/vendor/golang.org/x/tools/go/types/typeutil/callee.go b/vendor/golang.org/x/tools/go/types/typeutil/callee.go new file mode 100644 index 0000000000..38f596daf9 --- /dev/null +++ b/vendor/golang.org/x/tools/go/types/typeutil/callee.go @@ -0,0 +1,46 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package typeutil + +import ( + "go/ast" + "go/types" + + "golang.org/x/tools/go/ast/astutil" +) + +// Callee returns the named target of a function call, if any: +// a function, method, builtin, or variable. +func Callee(info *types.Info, call *ast.CallExpr) types.Object { + var obj types.Object + switch fun := astutil.Unparen(call.Fun).(type) { + case *ast.Ident: + obj = info.Uses[fun] // type, var, builtin, or declared func + case *ast.SelectorExpr: + if sel, ok := info.Selections[fun]; ok { + obj = sel.Obj() // method or field + } else { + obj = info.Uses[fun.Sel] // qualified identifier? + } + } + if _, ok := obj.(*types.TypeName); ok { + return nil // T(x) is a conversion, not a call + } + return obj +} + +// StaticCallee returns the target (function or method) of a static +// function call, if any. It returns nil for calls to builtins. +func StaticCallee(info *types.Info, call *ast.CallExpr) *types.Func { + if f, ok := Callee(info, call).(*types.Func); ok && !interfaceMethod(f) { + return f + } + return nil +} + +func interfaceMethod(f *types.Func) bool { + recv := f.Type().(*types.Signature).Recv() + return recv != nil && types.IsInterface(recv.Type()) +} diff --git a/vendor/golang.org/x/tools/go/types/typeutil/imports.go b/vendor/golang.org/x/tools/go/types/typeutil/imports.go new file mode 100644 index 0000000000..9c441dba9c --- /dev/null +++ b/vendor/golang.org/x/tools/go/types/typeutil/imports.go @@ -0,0 +1,31 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package typeutil + +import "go/types" + +// Dependencies returns all dependencies of the specified packages. +// +// Dependent packages appear in topological order: if package P imports +// package Q, Q appears earlier than P in the result. +// The algorithm follows import statements in the order they +// appear in the source code, so the result is a total order. +// +func Dependencies(pkgs ...*types.Package) []*types.Package { + var result []*types.Package + seen := make(map[*types.Package]bool) + var visit func(pkgs []*types.Package) + visit = func(pkgs []*types.Package) { + for _, p := range pkgs { + if !seen[p] { + seen[p] = true + visit(p.Imports()) + result = append(result, p) + } + } + } + visit(pkgs) + return result +} diff --git a/vendor/golang.org/x/tools/go/types/typeutil/map.go b/vendor/golang.org/x/tools/go/types/typeutil/map.go new file mode 100644 index 0000000000..c7f7545006 --- /dev/null +++ b/vendor/golang.org/x/tools/go/types/typeutil/map.go @@ -0,0 +1,313 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package typeutil defines various utilities for types, such as Map, +// a mapping from types.Type to interface{} values. +package typeutil // import "golang.org/x/tools/go/types/typeutil" + +import ( + "bytes" + "fmt" + "go/types" + "reflect" +) + +// Map is a hash-table-based mapping from types (types.Type) to +// arbitrary interface{} values. The concrete types that implement +// the Type interface are pointers. Since they are not canonicalized, +// == cannot be used to check for equivalence, and thus we cannot +// simply use a Go map. +// +// Just as with map[K]V, a nil *Map is a valid empty map. +// +// Not thread-safe. +// +type Map struct { + hasher Hasher // shared by many Maps + table map[uint32][]entry // maps hash to bucket; entry.key==nil means unused + length int // number of map entries +} + +// entry is an entry (key/value association) in a hash bucket. +type entry struct { + key types.Type + value interface{} +} + +// SetHasher sets the hasher used by Map. +// +// All Hashers are functionally equivalent but contain internal state +// used to cache the results of hashing previously seen types. +// +// A single Hasher created by MakeHasher() may be shared among many +// Maps. This is recommended if the instances have many keys in +// common, as it will amortize the cost of hash computation. +// +// A Hasher may grow without bound as new types are seen. Even when a +// type is deleted from the map, the Hasher never shrinks, since other +// types in the map may reference the deleted type indirectly. +// +// Hashers are not thread-safe, and read-only operations such as +// Map.Lookup require updates to the hasher, so a full Mutex lock (not a +// read-lock) is require around all Map operations if a shared +// hasher is accessed from multiple threads. +// +// If SetHasher is not called, the Map will create a private hasher at +// the first call to Insert. +// +func (m *Map) SetHasher(hasher Hasher) { + m.hasher = hasher +} + +// Delete removes the entry with the given key, if any. +// It returns true if the entry was found. +// +func (m *Map) Delete(key types.Type) bool { + if m != nil && m.table != nil { + hash := m.hasher.Hash(key) + bucket := m.table[hash] + for i, e := range bucket { + if e.key != nil && types.Identical(key, e.key) { + // We can't compact the bucket as it + // would disturb iterators. + bucket[i] = entry{} + m.length-- + return true + } + } + } + return false +} + +// At returns the map entry for the given key. +// The result is nil if the entry is not present. +// +func (m *Map) At(key types.Type) interface{} { + if m != nil && m.table != nil { + for _, e := range m.table[m.hasher.Hash(key)] { + if e.key != nil && types.Identical(key, e.key) { + return e.value + } + } + } + return nil +} + +// Set sets the map entry for key to val, +// and returns the previous entry, if any. +func (m *Map) Set(key types.Type, value interface{}) (prev interface{}) { + if m.table != nil { + hash := m.hasher.Hash(key) + bucket := m.table[hash] + var hole *entry + for i, e := range bucket { + if e.key == nil { + hole = &bucket[i] + } else if types.Identical(key, e.key) { + prev = e.value + bucket[i].value = value + return + } + } + + if hole != nil { + *hole = entry{key, value} // overwrite deleted entry + } else { + m.table[hash] = append(bucket, entry{key, value}) + } + } else { + if m.hasher.memo == nil { + m.hasher = MakeHasher() + } + hash := m.hasher.Hash(key) + m.table = map[uint32][]entry{hash: {entry{key, value}}} + } + + m.length++ + return +} + +// Len returns the number of map entries. +func (m *Map) Len() int { + if m != nil { + return m.length + } + return 0 +} + +// Iterate calls function f on each entry in the map in unspecified order. +// +// If f should mutate the map, Iterate provides the same guarantees as +// Go maps: if f deletes a map entry that Iterate has not yet reached, +// f will not be invoked for it, but if f inserts a map entry that +// Iterate has not yet reached, whether or not f will be invoked for +// it is unspecified. +// +func (m *Map) Iterate(f func(key types.Type, value interface{})) { + if m != nil { + for _, bucket := range m.table { + for _, e := range bucket { + if e.key != nil { + f(e.key, e.value) + } + } + } + } +} + +// Keys returns a new slice containing the set of map keys. +// The order is unspecified. +func (m *Map) Keys() []types.Type { + keys := make([]types.Type, 0, m.Len()) + m.Iterate(func(key types.Type, _ interface{}) { + keys = append(keys, key) + }) + return keys +} + +func (m *Map) toString(values bool) string { + if m == nil { + return "{}" + } + var buf bytes.Buffer + fmt.Fprint(&buf, "{") + sep := "" + m.Iterate(func(key types.Type, value interface{}) { + fmt.Fprint(&buf, sep) + sep = ", " + fmt.Fprint(&buf, key) + if values { + fmt.Fprintf(&buf, ": %q", value) + } + }) + fmt.Fprint(&buf, "}") + return buf.String() +} + +// String returns a string representation of the map's entries. +// Values are printed using fmt.Sprintf("%v", v). +// Order is unspecified. +// +func (m *Map) String() string { + return m.toString(true) +} + +// KeysString returns a string representation of the map's key set. +// Order is unspecified. +// +func (m *Map) KeysString() string { + return m.toString(false) +} + +//////////////////////////////////////////////////////////////////////// +// Hasher + +// A Hasher maps each type to its hash value. +// For efficiency, a hasher uses memoization; thus its memory +// footprint grows monotonically over time. +// Hashers are not thread-safe. +// Hashers have reference semantics. +// Call MakeHasher to create a Hasher. +type Hasher struct { + memo map[types.Type]uint32 +} + +// MakeHasher returns a new Hasher instance. +func MakeHasher() Hasher { + return Hasher{make(map[types.Type]uint32)} +} + +// Hash computes a hash value for the given type t such that +// Identical(t, t') => Hash(t) == Hash(t'). +func (h Hasher) Hash(t types.Type) uint32 { + hash, ok := h.memo[t] + if !ok { + hash = h.hashFor(t) + h.memo[t] = hash + } + return hash +} + +// hashString computes the Fowler–Noll–Vo hash of s. +func hashString(s string) uint32 { + var h uint32 + for i := 0; i < len(s); i++ { + h ^= uint32(s[i]) + h *= 16777619 + } + return h +} + +// hashFor computes the hash of t. +func (h Hasher) hashFor(t types.Type) uint32 { + // See Identical for rationale. + switch t := t.(type) { + case *types.Basic: + return uint32(t.Kind()) + + case *types.Array: + return 9043 + 2*uint32(t.Len()) + 3*h.Hash(t.Elem()) + + case *types.Slice: + return 9049 + 2*h.Hash(t.Elem()) + + case *types.Struct: + var hash uint32 = 9059 + for i, n := 0, t.NumFields(); i < n; i++ { + f := t.Field(i) + if f.Anonymous() { + hash += 8861 + } + hash += hashString(t.Tag(i)) + hash += hashString(f.Name()) // (ignore f.Pkg) + hash += h.Hash(f.Type()) + } + return hash + + case *types.Pointer: + return 9067 + 2*h.Hash(t.Elem()) + + case *types.Signature: + var hash uint32 = 9091 + if t.Variadic() { + hash *= 8863 + } + return hash + 3*h.hashTuple(t.Params()) + 5*h.hashTuple(t.Results()) + + case *types.Interface: + var hash uint32 = 9103 + for i, n := 0, t.NumMethods(); i < n; i++ { + // See go/types.identicalMethods for rationale. + // Method order is not significant. + // Ignore m.Pkg(). + m := t.Method(i) + hash += 3*hashString(m.Name()) + 5*h.Hash(m.Type()) + } + return hash + + case *types.Map: + return 9109 + 2*h.Hash(t.Key()) + 3*h.Hash(t.Elem()) + + case *types.Chan: + return 9127 + 2*uint32(t.Dir()) + 3*h.Hash(t.Elem()) + + case *types.Named: + // Not safe with a copying GC; objects may move. + return uint32(reflect.ValueOf(t.Obj()).Pointer()) + + case *types.Tuple: + return h.hashTuple(t) + } + panic(t) +} + +func (h Hasher) hashTuple(tuple *types.Tuple) uint32 { + // See go/types.identicalTypes for rationale. + n := tuple.Len() + var hash uint32 = 9137 + 2*uint32(n) + for i := 0; i < n; i++ { + hash += 3 * h.Hash(tuple.At(i).Type()) + } + return hash +} diff --git a/vendor/golang.org/x/tools/go/types/typeutil/methodsetcache.go b/vendor/golang.org/x/tools/go/types/typeutil/methodsetcache.go new file mode 100644 index 0000000000..32084610f4 --- /dev/null +++ b/vendor/golang.org/x/tools/go/types/typeutil/methodsetcache.go @@ -0,0 +1,72 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file implements a cache of method sets. + +package typeutil + +import ( + "go/types" + "sync" +) + +// A MethodSetCache records the method set of each type T for which +// MethodSet(T) is called so that repeat queries are fast. +// The zero value is a ready-to-use cache instance. +type MethodSetCache struct { + mu sync.Mutex + named map[*types.Named]struct{ value, pointer *types.MethodSet } // method sets for named N and *N + others map[types.Type]*types.MethodSet // all other types +} + +// MethodSet returns the method set of type T. It is thread-safe. +// +// If cache is nil, this function is equivalent to types.NewMethodSet(T). +// Utility functions can thus expose an optional *MethodSetCache +// parameter to clients that care about performance. +// +func (cache *MethodSetCache) MethodSet(T types.Type) *types.MethodSet { + if cache == nil { + return types.NewMethodSet(T) + } + cache.mu.Lock() + defer cache.mu.Unlock() + + switch T := T.(type) { + case *types.Named: + return cache.lookupNamed(T).value + + case *types.Pointer: + if N, ok := T.Elem().(*types.Named); ok { + return cache.lookupNamed(N).pointer + } + } + + // all other types + // (The map uses pointer equivalence, not type identity.) + mset := cache.others[T] + if mset == nil { + mset = types.NewMethodSet(T) + if cache.others == nil { + cache.others = make(map[types.Type]*types.MethodSet) + } + cache.others[T] = mset + } + return mset +} + +func (cache *MethodSetCache) lookupNamed(named *types.Named) struct{ value, pointer *types.MethodSet } { + if cache.named == nil { + cache.named = make(map[*types.Named]struct{ value, pointer *types.MethodSet }) + } + // Avoid recomputing mset(*T) for each distinct Pointer + // instance whose underlying type is a named type. + msets, ok := cache.named[named] + if !ok { + msets.value = types.NewMethodSet(named) + msets.pointer = types.NewMethodSet(types.NewPointer(named)) + cache.named[named] = msets + } + return msets +} diff --git a/vendor/golang.org/x/tools/go/types/typeutil/ui.go b/vendor/golang.org/x/tools/go/types/typeutil/ui.go new file mode 100644 index 0000000000..9849c24cef --- /dev/null +++ b/vendor/golang.org/x/tools/go/types/typeutil/ui.go @@ -0,0 +1,52 @@ +// Copyright 2014 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package typeutil + +// This file defines utilities for user interfaces that display types. + +import "go/types" + +// IntuitiveMethodSet returns the intuitive method set of a type T, +// which is the set of methods you can call on an addressable value of +// that type. +// +// The result always contains MethodSet(T), and is exactly MethodSet(T) +// for interface types and for pointer-to-concrete types. +// For all other concrete types T, the result additionally +// contains each method belonging to *T if there is no identically +// named method on T itself. +// +// This corresponds to user intuition about method sets; +// this function is intended only for user interfaces. +// +// The order of the result is as for types.MethodSet(T). +// +func IntuitiveMethodSet(T types.Type, msets *MethodSetCache) []*types.Selection { + isPointerToConcrete := func(T types.Type) bool { + ptr, ok := T.(*types.Pointer) + return ok && !types.IsInterface(ptr.Elem()) + } + + var result []*types.Selection + mset := msets.MethodSet(T) + if types.IsInterface(T) || isPointerToConcrete(T) { + for i, n := 0, mset.Len(); i < n; i++ { + result = append(result, mset.At(i)) + } + } else { + // T is some other concrete type. + // Report methods of T and *T, preferring those of T. + pmset := msets.MethodSet(types.NewPointer(T)) + for i, n := 0, pmset.Len(); i < n; i++ { + meth := pmset.At(i) + if m := mset.Lookup(meth.Obj().Pkg(), meth.Obj().Name()); m != nil { + meth = m + } + result = append(result, meth) + } + + } + return result +} diff --git a/vendor/golang.org/x/tools/internal/fastwalk/fastwalk.go b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk.go new file mode 100644 index 0000000000..7219c8e9ff --- /dev/null +++ b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk.go @@ -0,0 +1,196 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package fastwalk provides a faster version of filepath.Walk for file system +// scanning tools. +package fastwalk + +import ( + "errors" + "os" + "path/filepath" + "runtime" + "sync" +) + +// TraverseLink is used as a return value from WalkFuncs to indicate that the +// symlink named in the call may be traversed. +var TraverseLink = errors.New("fastwalk: traverse symlink, assuming target is a directory") + +// SkipFiles is a used as a return value from WalkFuncs to indicate that the +// callback should not be called for any other files in the current directory. +// Child directories will still be traversed. +var SkipFiles = errors.New("fastwalk: skip remaining files in directory") + +// Walk is a faster implementation of filepath.Walk. +// +// filepath.Walk's design necessarily calls os.Lstat on each file, +// even if the caller needs less info. +// Many tools need only the type of each file. +// On some platforms, this information is provided directly by the readdir +// system call, avoiding the need to stat each file individually. +// fastwalk_unix.go contains a fork of the syscall routines. +// +// See golang.org/issue/16399 +// +// Walk walks the file tree rooted at root, calling walkFn for +// each file or directory in the tree, including root. +// +// If fastWalk returns filepath.SkipDir, the directory is skipped. +// +// Unlike filepath.Walk: +// * file stat calls must be done by the user. +// The only provided metadata is the file type, which does not include +// any permission bits. +// * multiple goroutines stat the filesystem concurrently. The provided +// walkFn must be safe for concurrent use. +// * fastWalk can follow symlinks if walkFn returns the TraverseLink +// sentinel error. It is the walkFn's responsibility to prevent +// fastWalk from going into symlink cycles. +func Walk(root string, walkFn func(path string, typ os.FileMode) error) error { + // TODO(bradfitz): make numWorkers configurable? We used a + // minimum of 4 to give the kernel more info about multiple + // things we want, in hopes its I/O scheduling can take + // advantage of that. Hopefully most are in cache. Maybe 4 is + // even too low of a minimum. Profile more. + numWorkers := 4 + if n := runtime.NumCPU(); n > numWorkers { + numWorkers = n + } + + // Make sure to wait for all workers to finish, otherwise + // walkFn could still be called after returning. This Wait call + // runs after close(e.donec) below. + var wg sync.WaitGroup + defer wg.Wait() + + w := &walker{ + fn: walkFn, + enqueuec: make(chan walkItem, numWorkers), // buffered for performance + workc: make(chan walkItem, numWorkers), // buffered for performance + donec: make(chan struct{}), + + // buffered for correctness & not leaking goroutines: + resc: make(chan error, numWorkers), + } + defer close(w.donec) + + for i := 0; i < numWorkers; i++ { + wg.Add(1) + go w.doWork(&wg) + } + todo := []walkItem{{dir: root}} + out := 0 + for { + workc := w.workc + var workItem walkItem + if len(todo) == 0 { + workc = nil + } else { + workItem = todo[len(todo)-1] + } + select { + case workc <- workItem: + todo = todo[:len(todo)-1] + out++ + case it := <-w.enqueuec: + todo = append(todo, it) + case err := <-w.resc: + out-- + if err != nil { + return err + } + if out == 0 && len(todo) == 0 { + // It's safe to quit here, as long as the buffered + // enqueue channel isn't also readable, which might + // happen if the worker sends both another unit of + // work and its result before the other select was + // scheduled and both w.resc and w.enqueuec were + // readable. + select { + case it := <-w.enqueuec: + todo = append(todo, it) + default: + return nil + } + } + } + } +} + +// doWork reads directories as instructed (via workc) and runs the +// user's callback function. +func (w *walker) doWork(wg *sync.WaitGroup) { + defer wg.Done() + for { + select { + case <-w.donec: + return + case it := <-w.workc: + select { + case <-w.donec: + return + case w.resc <- w.walk(it.dir, !it.callbackDone): + } + } + } +} + +type walker struct { + fn func(path string, typ os.FileMode) error + + donec chan struct{} // closed on fastWalk's return + workc chan walkItem // to workers + enqueuec chan walkItem // from workers + resc chan error // from workers +} + +type walkItem struct { + dir string + callbackDone bool // callback already called; don't do it again +} + +func (w *walker) enqueue(it walkItem) { + select { + case w.enqueuec <- it: + case <-w.donec: + } +} + +func (w *walker) onDirEnt(dirName, baseName string, typ os.FileMode) error { + joined := dirName + string(os.PathSeparator) + baseName + if typ == os.ModeDir { + w.enqueue(walkItem{dir: joined}) + return nil + } + + err := w.fn(joined, typ) + if typ == os.ModeSymlink { + if err == TraverseLink { + // Set callbackDone so we don't call it twice for both the + // symlink-as-symlink and the symlink-as-directory later: + w.enqueue(walkItem{dir: joined, callbackDone: true}) + return nil + } + if err == filepath.SkipDir { + // Permit SkipDir on symlinks too. + return nil + } + } + return err +} + +func (w *walker) walk(root string, runUserCallback bool) error { + if runUserCallback { + err := w.fn(root, os.ModeDir) + if err == filepath.SkipDir { + return nil + } + if err != nil { + return err + } + } + + return readDir(root, w.onDirEnt) +} diff --git a/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_fileno.go b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_fileno.go new file mode 100644 index 0000000000..ccffec5adc --- /dev/null +++ b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_fileno.go @@ -0,0 +1,13 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build freebsd openbsd netbsd + +package fastwalk + +import "syscall" + +func direntInode(dirent *syscall.Dirent) uint64 { + return uint64(dirent.Fileno) +} diff --git a/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_ino.go b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_ino.go new file mode 100644 index 0000000000..ab7fbc0a9a --- /dev/null +++ b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_ino.go @@ -0,0 +1,14 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build linux darwin +// +build !appengine + +package fastwalk + +import "syscall" + +func direntInode(dirent *syscall.Dirent) uint64 { + return uint64(dirent.Ino) +} diff --git a/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_namlen_bsd.go b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_namlen_bsd.go new file mode 100644 index 0000000000..a3b26a7bae --- /dev/null +++ b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_namlen_bsd.go @@ -0,0 +1,13 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build darwin freebsd openbsd netbsd + +package fastwalk + +import "syscall" + +func direntNamlen(dirent *syscall.Dirent) uint64 { + return uint64(dirent.Namlen) +} diff --git a/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_namlen_linux.go b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_namlen_linux.go new file mode 100644 index 0000000000..61896ffe7e --- /dev/null +++ b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_dirent_namlen_linux.go @@ -0,0 +1,24 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build linux +// +build !appengine + +package fastwalk + +import ( + "bytes" + "syscall" + "unsafe" +) + +func direntNamlen(dirent *syscall.Dirent) uint64 { + const fixedHdr = uint16(unsafe.Offsetof(syscall.Dirent{}.Name)) + nameBuf := (*[unsafe.Sizeof(dirent.Name)]byte)(unsafe.Pointer(&dirent.Name[0])) + nameLen := bytes.IndexByte(nameBuf[:dirent.Reclen-fixedHdr], 0) + if nameLen < 0 { + panic("failed to find terminating 0 byte in dirent") + } + return uint64(nameLen) +} diff --git a/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_portable.go b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_portable.go new file mode 100644 index 0000000000..a906b87595 --- /dev/null +++ b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_portable.go @@ -0,0 +1,37 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build appengine !linux,!darwin,!freebsd,!openbsd,!netbsd + +package fastwalk + +import ( + "io/ioutil" + "os" +) + +// readDir calls fn for each directory entry in dirName. +// It does not descend into directories or follow symlinks. +// If fn returns a non-nil error, readDir returns with that error +// immediately. +func readDir(dirName string, fn func(dirName, entName string, typ os.FileMode) error) error { + fis, err := ioutil.ReadDir(dirName) + if err != nil { + return err + } + skipFiles := false + for _, fi := range fis { + if fi.Mode().IsRegular() && skipFiles { + continue + } + if err := fn(dirName, fi.Name(), fi.Mode()&os.ModeType); err != nil { + if err == SkipFiles { + skipFiles = true + continue + } + return err + } + } + return nil +} diff --git a/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_unix.go b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_unix.go new file mode 100644 index 0000000000..3369b1a0b2 --- /dev/null +++ b/vendor/golang.org/x/tools/internal/fastwalk/fastwalk_unix.go @@ -0,0 +1,127 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build linux darwin freebsd openbsd netbsd +// +build !appengine + +package fastwalk + +import ( + "fmt" + "os" + "syscall" + "unsafe" +) + +const blockSize = 8 << 10 + +// unknownFileMode is a sentinel (and bogus) os.FileMode +// value used to represent a syscall.DT_UNKNOWN Dirent.Type. +const unknownFileMode os.FileMode = os.ModeNamedPipe | os.ModeSocket | os.ModeDevice + +func readDir(dirName string, fn func(dirName, entName string, typ os.FileMode) error) error { + fd, err := syscall.Open(dirName, 0, 0) + if err != nil { + return &os.PathError{Op: "open", Path: dirName, Err: err} + } + defer syscall.Close(fd) + + // The buffer must be at least a block long. + buf := make([]byte, blockSize) // stack-allocated; doesn't escape + bufp := 0 // starting read position in buf + nbuf := 0 // end valid data in buf + skipFiles := false + for { + if bufp >= nbuf { + bufp = 0 + nbuf, err = syscall.ReadDirent(fd, buf) + if err != nil { + return os.NewSyscallError("readdirent", err) + } + if nbuf <= 0 { + return nil + } + } + consumed, name, typ := parseDirEnt(buf[bufp:nbuf]) + bufp += consumed + if name == "" || name == "." || name == ".." { + continue + } + // Fallback for filesystems (like old XFS) that don't + // support Dirent.Type and have DT_UNKNOWN (0) there + // instead. + if typ == unknownFileMode { + fi, err := os.Lstat(dirName + "/" + name) + if err != nil { + // It got deleted in the meantime. + if os.IsNotExist(err) { + continue + } + return err + } + typ = fi.Mode() & os.ModeType + } + if skipFiles && typ.IsRegular() { + continue + } + if err := fn(dirName, name, typ); err != nil { + if err == SkipFiles { + skipFiles = true + continue + } + return err + } + } +} + +func parseDirEnt(buf []byte) (consumed int, name string, typ os.FileMode) { + // golang.org/issue/15653 + dirent := (*syscall.Dirent)(unsafe.Pointer(&buf[0])) + if v := unsafe.Offsetof(dirent.Reclen) + unsafe.Sizeof(dirent.Reclen); uintptr(len(buf)) < v { + panic(fmt.Sprintf("buf size of %d smaller than dirent header size %d", len(buf), v)) + } + if len(buf) < int(dirent.Reclen) { + panic(fmt.Sprintf("buf size %d < record length %d", len(buf), dirent.Reclen)) + } + consumed = int(dirent.Reclen) + if direntInode(dirent) == 0 { // File absent in directory. + return + } + switch dirent.Type { + case syscall.DT_REG: + typ = 0 + case syscall.DT_DIR: + typ = os.ModeDir + case syscall.DT_LNK: + typ = os.ModeSymlink + case syscall.DT_BLK: + typ = os.ModeDevice + case syscall.DT_FIFO: + typ = os.ModeNamedPipe + case syscall.DT_SOCK: + typ = os.ModeSocket + case syscall.DT_UNKNOWN: + typ = unknownFileMode + default: + // Skip weird things. + // It's probably a DT_WHT (http://lwn.net/Articles/325369/) + // or something. Revisit if/when this package is moved outside + // of goimports. goimports only cares about regular files, + // symlinks, and directories. + return + } + + nameBuf := (*[unsafe.Sizeof(dirent.Name)]byte)(unsafe.Pointer(&dirent.Name[0])) + nameLen := direntNamlen(dirent) + + // Special cases for common things: + if nameLen == 1 && nameBuf[0] == '.' { + name = "." + } else if nameLen == 2 && nameBuf[0] == '.' && nameBuf[1] == '.' { + name = ".." + } else { + name = string(nameBuf[:nameLen]) + } + return +} diff --git a/vendor/golang.org/x/tools/internal/gopathwalk/walk.go b/vendor/golang.org/x/tools/internal/gopathwalk/walk.go new file mode 100644 index 0000000000..dc085fc160 --- /dev/null +++ b/vendor/golang.org/x/tools/internal/gopathwalk/walk.go @@ -0,0 +1,246 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package gopathwalk is like filepath.Walk but specialized for finding Go +// packages, particularly in $GOPATH and $GOROOT. +package gopathwalk + +import ( + "bufio" + "bytes" + "fmt" + "go/build" + "golang.org/x/tools/internal/fastwalk" + "io/ioutil" + "log" + "os" + "path/filepath" + "strings" +) + +// Options controls the behavior of a Walk call. +type Options struct { + Debug bool // Enable debug logging + ModulesEnabled bool // Search module caches. Also disables legacy goimports ignore rules. +} + +// RootType indicates the type of a Root. +type RootType int + +const ( + RootUnknown RootType = iota + RootGOROOT + RootGOPATH + RootCurrentModule + RootModuleCache +) + +// A Root is a starting point for a Walk. +type Root struct { + Path string + Type RootType +} + +// SrcDirsRoots returns the roots from build.Default.SrcDirs(). Not modules-compatible. +func SrcDirsRoots() []Root { + var roots []Root + roots = append(roots, Root{filepath.Join(build.Default.GOROOT, "src"), RootGOROOT}) + for _, p := range filepath.SplitList(build.Default.GOPATH) { + roots = append(roots, Root{filepath.Join(p, "src"), RootGOPATH}) + } + return roots +} + +// Walk walks Go source directories ($GOROOT, $GOPATH, etc) to find packages. +// For each package found, add will be called (concurrently) with the absolute +// paths of the containing source directory and the package directory. +// add will be called concurrently. +func Walk(roots []Root, add func(root Root, dir string), opts Options) { + for _, root := range roots { + walkDir(root, add, opts) + } +} + +func walkDir(root Root, add func(Root, string), opts Options) { + if _, err := os.Stat(root.Path); os.IsNotExist(err) { + if opts.Debug { + log.Printf("skipping nonexistant directory: %v", root.Path) + } + return + } + if opts.Debug { + log.Printf("scanning %s", root.Path) + } + w := &walker{ + root: root, + add: add, + opts: opts, + } + w.init() + if err := fastwalk.Walk(root.Path, w.walk); err != nil { + log.Printf("gopathwalk: scanning directory %v: %v", root.Path, err) + } + + if opts.Debug { + log.Printf("scanned %s", root.Path) + } +} + +// walker is the callback for fastwalk.Walk. +type walker struct { + root Root // The source directory to scan. + add func(Root, string) // The callback that will be invoked for every possible Go package dir. + opts Options // Options passed to Walk by the user. + + ignoredDirs []os.FileInfo // The ignored directories, loaded from .goimportsignore files. +} + +// init initializes the walker based on its Options. +func (w *walker) init() { + var ignoredPaths []string + if w.root.Type == RootModuleCache { + ignoredPaths = []string{"cache"} + } + if !w.opts.ModulesEnabled && w.root.Type == RootGOPATH { + ignoredPaths = w.getIgnoredDirs(w.root.Path) + ignoredPaths = append(ignoredPaths, "v", "mod") + } + + for _, p := range ignoredPaths { + full := filepath.Join(w.root.Path, p) + if fi, err := os.Stat(full); err == nil { + w.ignoredDirs = append(w.ignoredDirs, fi) + if w.opts.Debug { + log.Printf("Directory added to ignore list: %s", full) + } + } else if w.opts.Debug { + log.Printf("Error statting ignored directory: %v", err) + } + } +} + +// getIgnoredDirs reads an optional config file at /.goimportsignore +// of relative directories to ignore when scanning for go files. +// The provided path is one of the $GOPATH entries with "src" appended. +func (w *walker) getIgnoredDirs(path string) []string { + file := filepath.Join(path, ".goimportsignore") + slurp, err := ioutil.ReadFile(file) + if w.opts.Debug { + if err != nil { + log.Print(err) + } else { + log.Printf("Read %s", file) + } + } + if err != nil { + return nil + } + + var ignoredDirs []string + bs := bufio.NewScanner(bytes.NewReader(slurp)) + for bs.Scan() { + line := strings.TrimSpace(bs.Text()) + if line == "" || strings.HasPrefix(line, "#") { + continue + } + ignoredDirs = append(ignoredDirs, line) + } + return ignoredDirs +} + +func (w *walker) shouldSkipDir(fi os.FileInfo) bool { + for _, ignoredDir := range w.ignoredDirs { + if os.SameFile(fi, ignoredDir) { + return true + } + } + return false +} + +func (w *walker) walk(path string, typ os.FileMode) error { + dir := filepath.Dir(path) + if typ.IsRegular() { + if dir == w.root.Path { + // Doesn't make sense to have regular files + // directly in your $GOPATH/src or $GOROOT/src. + return fastwalk.SkipFiles + } + if !strings.HasSuffix(path, ".go") { + return nil + } + + w.add(w.root, dir) + return fastwalk.SkipFiles + } + if typ == os.ModeDir { + base := filepath.Base(path) + if base == "" || base[0] == '.' || base[0] == '_' || + base == "testdata" || (!w.opts.ModulesEnabled && base == "node_modules") { + return filepath.SkipDir + } + fi, err := os.Lstat(path) + if err == nil && w.shouldSkipDir(fi) { + return filepath.SkipDir + } + return nil + } + if typ == os.ModeSymlink { + base := filepath.Base(path) + if strings.HasPrefix(base, ".#") { + // Emacs noise. + return nil + } + fi, err := os.Lstat(path) + if err != nil { + // Just ignore it. + return nil + } + if w.shouldTraverse(dir, fi) { + return fastwalk.TraverseLink + } + } + return nil +} + +// shouldTraverse reports whether the symlink fi, found in dir, +// should be followed. It makes sure symlinks were never visited +// before to avoid symlink loops. +func (w *walker) shouldTraverse(dir string, fi os.FileInfo) bool { + path := filepath.Join(dir, fi.Name()) + target, err := filepath.EvalSymlinks(path) + if err != nil { + return false + } + ts, err := os.Stat(target) + if err != nil { + fmt.Fprintln(os.Stderr, err) + return false + } + if !ts.IsDir() { + return false + } + if w.shouldSkipDir(ts) { + return false + } + // Check for symlink loops by statting each directory component + // and seeing if any are the same file as ts. + for { + parent := filepath.Dir(path) + if parent == path { + // Made it to the root without seeing a cycle. + // Use this symlink. + return true + } + parentInfo, err := os.Stat(parent) + if err != nil { + return false + } + if os.SameFile(ts, parentInfo) { + // Cycle. Don't traverse. + return false + } + path = parent + } + +} diff --git a/vendor/golang.org/x/tools/internal/semver/semver.go b/vendor/golang.org/x/tools/internal/semver/semver.go new file mode 100644 index 0000000000..4af7118e55 --- /dev/null +++ b/vendor/golang.org/x/tools/internal/semver/semver.go @@ -0,0 +1,388 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package semver implements comparison of semantic version strings. +// In this package, semantic version strings must begin with a leading "v", +// as in "v1.0.0". +// +// The general form of a semantic version string accepted by this package is +// +// vMAJOR[.MINOR[.PATCH[-PRERELEASE][+BUILD]]] +// +// where square brackets indicate optional parts of the syntax; +// MAJOR, MINOR, and PATCH are decimal integers without extra leading zeros; +// PRERELEASE and BUILD are each a series of non-empty dot-separated identifiers +// using only alphanumeric characters and hyphens; and +// all-numeric PRERELEASE identifiers must not have leading zeros. +// +// This package follows Semantic Versioning 2.0.0 (see semver.org) +// with two exceptions. First, it requires the "v" prefix. Second, it recognizes +// vMAJOR and vMAJOR.MINOR (with no prerelease or build suffixes) +// as shorthands for vMAJOR.0.0 and vMAJOR.MINOR.0. +package semver + +// parsed returns the parsed form of a semantic version string. +type parsed struct { + major string + minor string + patch string + short string + prerelease string + build string + err string +} + +// IsValid reports whether v is a valid semantic version string. +func IsValid(v string) bool { + _, ok := parse(v) + return ok +} + +// Canonical returns the canonical formatting of the semantic version v. +// It fills in any missing .MINOR or .PATCH and discards build metadata. +// Two semantic versions compare equal only if their canonical formattings +// are identical strings. +// The canonical invalid semantic version is the empty string. +func Canonical(v string) string { + p, ok := parse(v) + if !ok { + return "" + } + if p.build != "" { + return v[:len(v)-len(p.build)] + } + if p.short != "" { + return v + p.short + } + return v +} + +// Major returns the major version prefix of the semantic version v. +// For example, Major("v2.1.0") == "v2". +// If v is an invalid semantic version string, Major returns the empty string. +func Major(v string) string { + pv, ok := parse(v) + if !ok { + return "" + } + return v[:1+len(pv.major)] +} + +// MajorMinor returns the major.minor version prefix of the semantic version v. +// For example, MajorMinor("v2.1.0") == "v2.1". +// If v is an invalid semantic version string, MajorMinor returns the empty string. +func MajorMinor(v string) string { + pv, ok := parse(v) + if !ok { + return "" + } + i := 1 + len(pv.major) + if j := i + 1 + len(pv.minor); j <= len(v) && v[i] == '.' && v[i+1:j] == pv.minor { + return v[:j] + } + return v[:i] + "." + pv.minor +} + +// Prerelease returns the prerelease suffix of the semantic version v. +// For example, Prerelease("v2.1.0-pre+meta") == "-pre". +// If v is an invalid semantic version string, Prerelease returns the empty string. +func Prerelease(v string) string { + pv, ok := parse(v) + if !ok { + return "" + } + return pv.prerelease +} + +// Build returns the build suffix of the semantic version v. +// For example, Build("v2.1.0+meta") == "+meta". +// If v is an invalid semantic version string, Build returns the empty string. +func Build(v string) string { + pv, ok := parse(v) + if !ok { + return "" + } + return pv.build +} + +// Compare returns an integer comparing two versions according to +// according to semantic version precedence. +// The result will be 0 if v == w, -1 if v < w, or +1 if v > w. +// +// An invalid semantic version string is considered less than a valid one. +// All invalid semantic version strings compare equal to each other. +func Compare(v, w string) int { + pv, ok1 := parse(v) + pw, ok2 := parse(w) + if !ok1 && !ok2 { + return 0 + } + if !ok1 { + return -1 + } + if !ok2 { + return +1 + } + if c := compareInt(pv.major, pw.major); c != 0 { + return c + } + if c := compareInt(pv.minor, pw.minor); c != 0 { + return c + } + if c := compareInt(pv.patch, pw.patch); c != 0 { + return c + } + return comparePrerelease(pv.prerelease, pw.prerelease) +} + +// Max canonicalizes its arguments and then returns the version string +// that compares greater. +func Max(v, w string) string { + v = Canonical(v) + w = Canonical(w) + if Compare(v, w) > 0 { + return v + } + return w +} + +func parse(v string) (p parsed, ok bool) { + if v == "" || v[0] != 'v' { + p.err = "missing v prefix" + return + } + p.major, v, ok = parseInt(v[1:]) + if !ok { + p.err = "bad major version" + return + } + if v == "" { + p.minor = "0" + p.patch = "0" + p.short = ".0.0" + return + } + if v[0] != '.' { + p.err = "bad minor prefix" + ok = false + return + } + p.minor, v, ok = parseInt(v[1:]) + if !ok { + p.err = "bad minor version" + return + } + if v == "" { + p.patch = "0" + p.short = ".0" + return + } + if v[0] != '.' { + p.err = "bad patch prefix" + ok = false + return + } + p.patch, v, ok = parseInt(v[1:]) + if !ok { + p.err = "bad patch version" + return + } + if len(v) > 0 && v[0] == '-' { + p.prerelease, v, ok = parsePrerelease(v) + if !ok { + p.err = "bad prerelease" + return + } + } + if len(v) > 0 && v[0] == '+' { + p.build, v, ok = parseBuild(v) + if !ok { + p.err = "bad build" + return + } + } + if v != "" { + p.err = "junk on end" + ok = false + return + } + ok = true + return +} + +func parseInt(v string) (t, rest string, ok bool) { + if v == "" { + return + } + if v[0] < '0' || '9' < v[0] { + return + } + i := 1 + for i < len(v) && '0' <= v[i] && v[i] <= '9' { + i++ + } + if v[0] == '0' && i != 1 { + return + } + return v[:i], v[i:], true +} + +func parsePrerelease(v string) (t, rest string, ok bool) { + // "A pre-release version MAY be denoted by appending a hyphen and + // a series of dot separated identifiers immediately following the patch version. + // Identifiers MUST comprise only ASCII alphanumerics and hyphen [0-9A-Za-z-]. + // Identifiers MUST NOT be empty. Numeric identifiers MUST NOT include leading zeroes." + if v == "" || v[0] != '-' { + return + } + i := 1 + start := 1 + for i < len(v) && v[i] != '+' { + if !isIdentChar(v[i]) && v[i] != '.' { + return + } + if v[i] == '.' { + if start == i || isBadNum(v[start:i]) { + return + } + start = i + 1 + } + i++ + } + if start == i || isBadNum(v[start:i]) { + return + } + return v[:i], v[i:], true +} + +func parseBuild(v string) (t, rest string, ok bool) { + if v == "" || v[0] != '+' { + return + } + i := 1 + start := 1 + for i < len(v) { + if !isIdentChar(v[i]) { + return + } + if v[i] == '.' { + if start == i { + return + } + start = i + 1 + } + i++ + } + if start == i { + return + } + return v[:i], v[i:], true +} + +func isIdentChar(c byte) bool { + return 'A' <= c && c <= 'Z' || 'a' <= c && c <= 'z' || '0' <= c && c <= '9' || c == '-' +} + +func isBadNum(v string) bool { + i := 0 + for i < len(v) && '0' <= v[i] && v[i] <= '9' { + i++ + } + return i == len(v) && i > 1 && v[0] == '0' +} + +func isNum(v string) bool { + i := 0 + for i < len(v) && '0' <= v[i] && v[i] <= '9' { + i++ + } + return i == len(v) +} + +func compareInt(x, y string) int { + if x == y { + return 0 + } + if len(x) < len(y) { + return -1 + } + if len(x) > len(y) { + return +1 + } + if x < y { + return -1 + } else { + return +1 + } +} + +func comparePrerelease(x, y string) int { + // "When major, minor, and patch are equal, a pre-release version has + // lower precedence than a normal version. + // Example: 1.0.0-alpha < 1.0.0. + // Precedence for two pre-release versions with the same major, minor, + // and patch version MUST be determined by comparing each dot separated + // identifier from left to right until a difference is found as follows: + // identifiers consisting of only digits are compared numerically and + // identifiers with letters or hyphens are compared lexically in ASCII + // sort order. Numeric identifiers always have lower precedence than + // non-numeric identifiers. A larger set of pre-release fields has a + // higher precedence than a smaller set, if all of the preceding + // identifiers are equal. + // Example: 1.0.0-alpha < 1.0.0-alpha.1 < 1.0.0-alpha.beta < + // 1.0.0-beta < 1.0.0-beta.2 < 1.0.0-beta.11 < 1.0.0-rc.1 < 1.0.0." + if x == y { + return 0 + } + if x == "" { + return +1 + } + if y == "" { + return -1 + } + for x != "" && y != "" { + x = x[1:] // skip - or . + y = y[1:] // skip - or . + var dx, dy string + dx, x = nextIdent(x) + dy, y = nextIdent(y) + if dx != dy { + ix := isNum(dx) + iy := isNum(dy) + if ix != iy { + if ix { + return -1 + } else { + return +1 + } + } + if ix { + if len(dx) < len(dy) { + return -1 + } + if len(dx) > len(dy) { + return +1 + } + } + if dx < dy { + return -1 + } else { + return +1 + } + } + } + if x == "" { + return -1 + } else { + return +1 + } +} + +func nextIdent(x string) (dx, rest string) { + i := 0 + for i < len(x) && x[i] != '.' { + i++ + } + return x[:i], x[i:] +} diff --git a/vendor/honnef.co/go/tools/LICENSE b/vendor/honnef.co/go/tools/LICENSE new file mode 100644 index 0000000000..dfd0314546 --- /dev/null +++ b/vendor/honnef.co/go/tools/LICENSE @@ -0,0 +1,20 @@ +Copyright (c) 2016 Dominik Honnef + +Permission is hereby granted, free of charge, to any person obtaining +a copy of this software and associated documentation files (the +"Software"), to deal in the Software without restriction, including +without limitation the rights to use, copy, modify, merge, publish, +distribute, sublicense, and/or sell copies of the Software, and to +permit persons to whom the Software is furnished to do so, subject to +the following conditions: + +The above copyright notice and this permission notice shall be +included in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE +LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. diff --git a/vendor/honnef.co/go/tools/arg/arg.go b/vendor/honnef.co/go/tools/arg/arg.go new file mode 100644 index 0000000000..d9e42dbea7 --- /dev/null +++ b/vendor/honnef.co/go/tools/arg/arg.go @@ -0,0 +1,39 @@ +package arg + +var args = map[string]int{ + "(*sync.Pool).Put.x": 0, + "(*text/template.Template).Parse.text": 0, + "(io.Seeker).Seek.offset": 0, + "(time.Time).Sub.u": 0, + "append.elems": 1, + "append.slice": 0, + "bytes.Equal.a": 0, + "bytes.Equal.b": 1, + "encoding/binary.Write.data": 2, + "errors.New.text": 0, + "fmt.Printf.format": 0, + "fmt.Sprintf.a[0]": 1, + "fmt.Sprintf.format": 0, + "len.v": 0, + "make.size[0]": 1, + "make.size[1]": 2, + "make.t": 0, + "net/url.Parse.rawurl": 0, + "os.OpenFile.flag": 1, + "os/exec.Command.name": 0, + "os/signal.Notify.c": 0, + "regexp.Compile.expr": 0, + "runtime.SetFinalizer.finalizer": 1, + "runtime.SetFinalizer.obj": 0, + "sort.Sort.data": 0, + "time.Parse.layout": 0, + "time.Sleep.d": 0, +} + +func Arg(name string) int { + n, ok := args[name] + if !ok { + panic("unknown argument " + name) + } + return n +} diff --git a/vendor/honnef.co/go/tools/callgraph/callgraph.go b/vendor/honnef.co/go/tools/callgraph/callgraph.go new file mode 100644 index 0000000000..d93a20a3a1 --- /dev/null +++ b/vendor/honnef.co/go/tools/callgraph/callgraph.go @@ -0,0 +1,129 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +/* + +Package callgraph defines the call graph and various algorithms +and utilities to operate on it. + +A call graph is a labelled directed graph whose nodes represent +functions and whose edge labels represent syntactic function call +sites. The presence of a labelled edge (caller, site, callee) +indicates that caller may call callee at the specified call site. + +A call graph is a multigraph: it may contain multiple edges (caller, +*, callee) connecting the same pair of nodes, so long as the edges +differ by label; this occurs when one function calls another function +from multiple call sites. Also, it may contain multiple edges +(caller, site, *) that differ only by callee; this indicates a +polymorphic call. + +A SOUND call graph is one that overapproximates the dynamic calling +behaviors of the program in all possible executions. One call graph +is more PRECISE than another if it is a smaller overapproximation of +the dynamic behavior. + +All call graphs have a synthetic root node which is responsible for +calling main() and init(). + +Calls to built-in functions (e.g. panic, println) are not represented +in the call graph; they are treated like built-in operators of the +language. + +*/ +package callgraph // import "honnef.co/go/tools/callgraph" + +// TODO(adonovan): add a function to eliminate wrappers from the +// callgraph, preserving topology. +// More generally, we could eliminate "uninteresting" nodes such as +// nodes from packages we don't care about. + +import ( + "fmt" + "go/token" + + "honnef.co/go/tools/ssa" +) + +// A Graph represents a call graph. +// +// A graph may contain nodes that are not reachable from the root. +// If the call graph is sound, such nodes indicate unreachable +// functions. +// +type Graph struct { + Root *Node // the distinguished root node + Nodes map[*ssa.Function]*Node // all nodes by function +} + +// New returns a new Graph with the specified root node. +func New(root *ssa.Function) *Graph { + g := &Graph{Nodes: make(map[*ssa.Function]*Node)} + g.Root = g.CreateNode(root) + return g +} + +// CreateNode returns the Node for fn, creating it if not present. +func (g *Graph) CreateNode(fn *ssa.Function) *Node { + n, ok := g.Nodes[fn] + if !ok { + n = &Node{Func: fn, ID: len(g.Nodes)} + g.Nodes[fn] = n + } + return n +} + +// A Node represents a node in a call graph. +type Node struct { + Func *ssa.Function // the function this node represents + ID int // 0-based sequence number + In []*Edge // unordered set of incoming call edges (n.In[*].Callee == n) + Out []*Edge // unordered set of outgoing call edges (n.Out[*].Caller == n) +} + +func (n *Node) String() string { + return fmt.Sprintf("n%d:%s", n.ID, n.Func) +} + +// A Edge represents an edge in the call graph. +// +// Site is nil for edges originating in synthetic or intrinsic +// functions, e.g. reflect.Call or the root of the call graph. +type Edge struct { + Caller *Node + Site ssa.CallInstruction + Callee *Node +} + +func (e Edge) String() string { + return fmt.Sprintf("%s --> %s", e.Caller, e.Callee) +} + +func (e Edge) Description() string { + var prefix string + switch e.Site.(type) { + case nil: + return "synthetic call" + case *ssa.Go: + prefix = "concurrent " + case *ssa.Defer: + prefix = "deferred " + } + return prefix + e.Site.Common().Description() +} + +func (e Edge) Pos() token.Pos { + if e.Site == nil { + return token.NoPos + } + return e.Site.Pos() +} + +// AddEdge adds the edge (caller, site, callee) to the call graph. +// Elimination of duplicate edges is the caller's responsibility. +func AddEdge(caller *Node, site ssa.CallInstruction, callee *Node) { + e := &Edge{caller, site, callee} + callee.In = append(callee.In, e) + caller.Out = append(caller.Out, e) +} diff --git a/vendor/honnef.co/go/tools/callgraph/static/static.go b/vendor/honnef.co/go/tools/callgraph/static/static.go new file mode 100644 index 0000000000..5444e84113 --- /dev/null +++ b/vendor/honnef.co/go/tools/callgraph/static/static.go @@ -0,0 +1,35 @@ +// Package static computes the call graph of a Go program containing +// only static call edges. +package static // import "honnef.co/go/tools/callgraph/static" + +import ( + "honnef.co/go/tools/callgraph" + "honnef.co/go/tools/ssa" + "honnef.co/go/tools/ssa/ssautil" +) + +// CallGraph computes the call graph of the specified program +// considering only static calls. +// +func CallGraph(prog *ssa.Program) *callgraph.Graph { + cg := callgraph.New(nil) // TODO(adonovan) eliminate concept of rooted callgraph + + // TODO(adonovan): opt: use only a single pass over the ssa.Program. + // TODO(adonovan): opt: this is slower than RTA (perhaps because + // the lower precision means so many edges are allocated)! + for f := range ssautil.AllFunctions(prog) { + fnode := cg.CreateNode(f) + for _, b := range f.Blocks { + for _, instr := range b.Instrs { + if site, ok := instr.(ssa.CallInstruction); ok { + if g := site.Common().StaticCallee(); g != nil { + gnode := cg.CreateNode(g) + callgraph.AddEdge(fnode, site, gnode) + } + } + } + } + } + + return cg +} diff --git a/vendor/honnef.co/go/tools/callgraph/util.go b/vendor/honnef.co/go/tools/callgraph/util.go new file mode 100644 index 0000000000..7aeda96415 --- /dev/null +++ b/vendor/honnef.co/go/tools/callgraph/util.go @@ -0,0 +1,181 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package callgraph + +import "honnef.co/go/tools/ssa" + +// This file provides various utilities over call graphs, such as +// visitation and path search. + +// CalleesOf returns a new set containing all direct callees of the +// caller node. +// +func CalleesOf(caller *Node) map[*Node]bool { + callees := make(map[*Node]bool) + for _, e := range caller.Out { + callees[e.Callee] = true + } + return callees +} + +// GraphVisitEdges visits all the edges in graph g in depth-first order. +// The edge function is called for each edge in postorder. If it +// returns non-nil, visitation stops and GraphVisitEdges returns that +// value. +// +func GraphVisitEdges(g *Graph, edge func(*Edge) error) error { + seen := make(map[*Node]bool) + var visit func(n *Node) error + visit = func(n *Node) error { + if !seen[n] { + seen[n] = true + for _, e := range n.Out { + if err := visit(e.Callee); err != nil { + return err + } + if err := edge(e); err != nil { + return err + } + } + } + return nil + } + for _, n := range g.Nodes { + if err := visit(n); err != nil { + return err + } + } + return nil +} + +// PathSearch finds an arbitrary path starting at node start and +// ending at some node for which isEnd() returns true. On success, +// PathSearch returns the path as an ordered list of edges; on +// failure, it returns nil. +// +func PathSearch(start *Node, isEnd func(*Node) bool) []*Edge { + stack := make([]*Edge, 0, 32) + seen := make(map[*Node]bool) + var search func(n *Node) []*Edge + search = func(n *Node) []*Edge { + if !seen[n] { + seen[n] = true + if isEnd(n) { + return stack + } + for _, e := range n.Out { + stack = append(stack, e) // push + if found := search(e.Callee); found != nil { + return found + } + stack = stack[:len(stack)-1] // pop + } + } + return nil + } + return search(start) +} + +// DeleteSyntheticNodes removes from call graph g all nodes for +// synthetic functions (except g.Root and package initializers), +// preserving the topology. In effect, calls to synthetic wrappers +// are "inlined". +// +func (g *Graph) DeleteSyntheticNodes() { + // Measurements on the standard library and go.tools show that + // resulting graph has ~15% fewer nodes and 4-8% fewer edges + // than the input. + // + // Inlining a wrapper of in-degree m, out-degree n adds m*n + // and removes m+n edges. Since most wrappers are monomorphic + // (n=1) this results in a slight reduction. Polymorphic + // wrappers (n>1), e.g. from embedding an interface value + // inside a struct to satisfy some interface, cause an + // increase in the graph, but they seem to be uncommon. + + // Hash all existing edges to avoid creating duplicates. + edges := make(map[Edge]bool) + for _, cgn := range g.Nodes { + for _, e := range cgn.Out { + edges[*e] = true + } + } + for fn, cgn := range g.Nodes { + if cgn == g.Root || fn.Synthetic == "" || isInit(cgn.Func) { + continue // keep + } + for _, eIn := range cgn.In { + for _, eOut := range cgn.Out { + newEdge := Edge{eIn.Caller, eIn.Site, eOut.Callee} + if edges[newEdge] { + continue // don't add duplicate + } + AddEdge(eIn.Caller, eIn.Site, eOut.Callee) + edges[newEdge] = true + } + } + g.DeleteNode(cgn) + } +} + +func isInit(fn *ssa.Function) bool { + return fn.Pkg != nil && fn.Pkg.Func("init") == fn +} + +// DeleteNode removes node n and its edges from the graph g. +// (NB: not efficient for batch deletion.) +func (g *Graph) DeleteNode(n *Node) { + n.deleteIns() + n.deleteOuts() + delete(g.Nodes, n.Func) +} + +// deleteIns deletes all incoming edges to n. +func (n *Node) deleteIns() { + for _, e := range n.In { + removeOutEdge(e) + } + n.In = nil +} + +// deleteOuts deletes all outgoing edges from n. +func (n *Node) deleteOuts() { + for _, e := range n.Out { + removeInEdge(e) + } + n.Out = nil +} + +// removeOutEdge removes edge.Caller's outgoing edge 'edge'. +func removeOutEdge(edge *Edge) { + caller := edge.Caller + n := len(caller.Out) + for i, e := range caller.Out { + if e == edge { + // Replace it with the final element and shrink the slice. + caller.Out[i] = caller.Out[n-1] + caller.Out[n-1] = nil // aid GC + caller.Out = caller.Out[:n-1] + return + } + } + panic("edge not found: " + edge.String()) +} + +// removeInEdge removes edge.Callee's incoming edge 'edge'. +func removeInEdge(edge *Edge) { + caller := edge.Callee + n := len(caller.In) + for i, e := range caller.In { + if e == edge { + // Replace it with the final element and shrink the slice. + caller.In[i] = caller.In[n-1] + caller.In[n-1] = nil // aid GC + caller.In = caller.In[:n-1] + return + } + } + panic("edge not found: " + edge.String()) +} diff --git a/vendor/honnef.co/go/tools/cmd/staticcheck/README.md b/vendor/honnef.co/go/tools/cmd/staticcheck/README.md new file mode 100644 index 0000000000..127d8edf37 --- /dev/null +++ b/vendor/honnef.co/go/tools/cmd/staticcheck/README.md @@ -0,0 +1,15 @@ +# staticcheck + +_staticcheck_ offers extensive analysis of Go code, covering a myriad +of categories. It will detect bugs, suggest code simplifications, +point out dead code, and more. + +## Installation + + go get honnef.co/go/tools/cmd/staticcheck + +## Documentation + +Detailed documentation can be found on +[staticcheck.io](https://staticcheck.io/docs/). + diff --git a/vendor/honnef.co/go/tools/cmd/staticcheck/staticcheck.go b/vendor/honnef.co/go/tools/cmd/staticcheck/staticcheck.go new file mode 100644 index 0000000000..3c8d964759 --- /dev/null +++ b/vendor/honnef.co/go/tools/cmd/staticcheck/staticcheck.go @@ -0,0 +1,30 @@ +// staticcheck analyses Go code and makes it better. +package main // import "honnef.co/go/tools/cmd/staticcheck" + +import ( + "os" + + "honnef.co/go/tools/lint" + "honnef.co/go/tools/lint/lintutil" + "honnef.co/go/tools/simple" + "honnef.co/go/tools/staticcheck" + "honnef.co/go/tools/stylecheck" + "honnef.co/go/tools/unused" +) + +func main() { + fs := lintutil.FlagSet("staticcheck") + fs.Parse(os.Args[1:]) + + checkers := []lint.Checker{ + simple.NewChecker(), + staticcheck.NewChecker(), + stylecheck.NewChecker(), + } + + uc := unused.NewChecker(unused.CheckAll) + uc.ConsiderReflection = true + checkers = append(checkers, unused.NewLintChecker(uc)) + + lintutil.ProcessFlagSet(checkers, fs) +} diff --git a/vendor/honnef.co/go/tools/config/config.go b/vendor/honnef.co/go/tools/config/config.go new file mode 100644 index 0000000000..142dd75e83 --- /dev/null +++ b/vendor/honnef.co/go/tools/config/config.go @@ -0,0 +1,162 @@ +package config + +import ( + "os" + "path/filepath" + + "github.com/BurntSushi/toml" +) + +func mergeLists(a, b []string) []string { + out := make([]string, 0, len(a)+len(b)) + for _, el := range b { + if el == "inherit" { + out = append(out, a...) + } else { + out = append(out, el) + } + } + + return out +} + +func normalizeList(list []string) []string { + if len(list) > 1 { + nlist := make([]string, 0, len(list)) + nlist = append(nlist, list[0]) + for i, el := range list[1:] { + if el != list[i] { + nlist = append(nlist, el) + } + } + list = nlist + } + + for _, el := range list { + if el == "inherit" { + // This should never happen, because the default config + // should not use "inherit" + panic(`unresolved "inherit"`) + } + } + + return list +} + +func (cfg Config) Merge(ocfg Config) Config { + if ocfg.Checks != nil { + cfg.Checks = mergeLists(cfg.Checks, ocfg.Checks) + } + if ocfg.Initialisms != nil { + cfg.Initialisms = mergeLists(cfg.Initialisms, ocfg.Initialisms) + } + if ocfg.DotImportWhitelist != nil { + cfg.DotImportWhitelist = mergeLists(cfg.DotImportWhitelist, ocfg.DotImportWhitelist) + } + if ocfg.HTTPStatusCodeWhitelist != nil { + cfg.HTTPStatusCodeWhitelist = mergeLists(cfg.HTTPStatusCodeWhitelist, ocfg.HTTPStatusCodeWhitelist) + } + return cfg +} + +type Config struct { + // TODO(dh): this implementation makes it impossible for external + // clients to add their own checkers with configuration. At the + // moment, we don't really care about that; we don't encourage + // that people use this package. In the future, we may. The + // obvious solution would be using map[string]interface{}, but + // that's obviously subpar. + + Checks []string `toml:"checks"` + Initialisms []string `toml:"initialisms"` + DotImportWhitelist []string `toml:"dot_import_whitelist"` + HTTPStatusCodeWhitelist []string `toml:"http_status_code_whitelist"` +} + +var defaultConfig = Config{ + Checks: []string{"all", "-ST1003"}, + Initialisms: []string{ + "ACL", "API", "ASCII", "CPU", "CSS", "DNS", + "EOF", "GUID", "HTML", "HTTP", "HTTPS", "ID", + "IP", "JSON", "QPS", "RAM", "RPC", "SLA", + "SMTP", "SQL", "SSH", "TCP", "TLS", "TTL", + "UDP", "UI", "GID", "UID", "UUID", "URI", + "URL", "UTF8", "VM", "XML", "XMPP", "XSRF", + "XSS", + }, + DotImportWhitelist: []string{}, + HTTPStatusCodeWhitelist: []string{"200", "400", "404", "500"}, +} + +const configName = "staticcheck.conf" + +func parseConfigs(dir string) ([]Config, error) { + var out []Config + + // TODO(dh): consider stopping at the GOPATH/module boundary + for dir != "" { + f, err := os.Open(filepath.Join(dir, configName)) + if os.IsNotExist(err) { + ndir := filepath.Dir(dir) + if ndir == dir { + break + } + dir = ndir + continue + } + if err != nil { + return nil, err + } + var cfg Config + _, err = toml.DecodeReader(f, &cfg) + f.Close() + if err != nil { + return nil, err + } + out = append(out, cfg) + ndir := filepath.Dir(dir) + if ndir == dir { + break + } + dir = ndir + } + out = append(out, defaultConfig) + if len(out) < 2 { + return out, nil + } + for i := 0; i < len(out)/2; i++ { + out[i], out[len(out)-1-i] = out[len(out)-1-i], out[i] + } + return out, nil +} + +func mergeConfigs(confs []Config) Config { + if len(confs) == 0 { + // This shouldn't happen because we always have at least a + // default config. + panic("trying to merge zero configs") + } + if len(confs) == 1 { + return confs[0] + } + conf := confs[0] + for _, oconf := range confs[1:] { + conf = conf.Merge(oconf) + } + return conf +} + +func Load(dir string) (Config, error) { + confs, err := parseConfigs(dir) + if err != nil { + return Config{}, err + } + conf := mergeConfigs(confs) + + conf.Checks = normalizeList(conf.Checks) + conf.Initialisms = normalizeList(conf.Initialisms) + conf.DotImportWhitelist = normalizeList(conf.DotImportWhitelist) + conf.HTTPStatusCodeWhitelist = normalizeList(conf.HTTPStatusCodeWhitelist) + + return conf, nil +} diff --git a/vendor/honnef.co/go/tools/config/example.conf b/vendor/honnef.co/go/tools/config/example.conf new file mode 100644 index 0000000000..5ffc597f99 --- /dev/null +++ b/vendor/honnef.co/go/tools/config/example.conf @@ -0,0 +1,10 @@ +checks = ["all", "-ST1003", "-ST1014"] +initialisms = ["ACL", "API", "ASCII", "CPU", "CSS", "DNS", + "EOF", "GUID", "HTML", "HTTP", "HTTPS", "ID", + "IP", "JSON", "QPS", "RAM", "RPC", "SLA", + "SMTP", "SQL", "SSH", "TCP", "TLS", "TTL", + "UDP", "UI", "GID", "UID", "UUID", "URI", + "URL", "UTF8", "VM", "XML", "XMPP", "XSRF", + "XSS"] +dot_import_whitelist = [] +http_status_code_whitelist = ["200", "400", "404", "500"] diff --git a/vendor/honnef.co/go/tools/deprecated/stdlib.go b/vendor/honnef.co/go/tools/deprecated/stdlib.go new file mode 100644 index 0000000000..b6b217c3e3 --- /dev/null +++ b/vendor/honnef.co/go/tools/deprecated/stdlib.go @@ -0,0 +1,54 @@ +package deprecated + +type Deprecation struct { + DeprecatedSince int + AlternativeAvailableSince int +} + +var Stdlib = map[string]Deprecation{ + "image/jpeg.Reader": {4, 0}, + // FIXME(dh): AllowBinary isn't being detected as deprecated + // because the comment has a newline right after "Deprecated:" + "go/build.AllowBinary": {7, 7}, + "(archive/zip.FileHeader).CompressedSize": {1, 1}, + "(archive/zip.FileHeader).UncompressedSize": {1, 1}, + "(go/doc.Package).Bugs": {1, 1}, + "os.SEEK_SET": {7, 7}, + "os.SEEK_CUR": {7, 7}, + "os.SEEK_END": {7, 7}, + "(net.Dialer).Cancel": {7, 7}, + "runtime.CPUProfile": {9, 0}, + "compress/flate.ReadError": {6, 6}, + "compress/flate.WriteError": {6, 6}, + "path/filepath.HasPrefix": {0, 0}, + "(net/http.Transport).Dial": {7, 7}, + "(*net/http.Transport).CancelRequest": {6, 5}, + "net/http.ErrWriteAfterFlush": {7, 0}, + "net/http.ErrHeaderTooLong": {8, 0}, + "net/http.ErrShortBody": {8, 0}, + "net/http.ErrMissingContentLength": {8, 0}, + "net/http/httputil.ErrPersistEOF": {0, 0}, + "net/http/httputil.ErrClosed": {0, 0}, + "net/http/httputil.ErrPipeline": {0, 0}, + "net/http/httputil.ServerConn": {0, 0}, + "net/http/httputil.NewServerConn": {0, 0}, + "net/http/httputil.ClientConn": {0, 0}, + "net/http/httputil.NewClientConn": {0, 0}, + "net/http/httputil.NewProxyClientConn": {0, 0}, + "(net/http.Request).Cancel": {7, 7}, + "(text/template/parse.PipeNode).Line": {1, 1}, + "(text/template/parse.ActionNode).Line": {1, 1}, + "(text/template/parse.BranchNode).Line": {1, 1}, + "(text/template/parse.TemplateNode).Line": {1, 1}, + "database/sql/driver.ColumnConverter": {9, 9}, + "database/sql/driver.Execer": {8, 8}, + "database/sql/driver.Queryer": {8, 8}, + "(database/sql/driver.Conn).Begin": {8, 8}, + "(database/sql/driver.Stmt).Exec": {8, 8}, + "(database/sql/driver.Stmt).Query": {8, 8}, + "syscall.StringByteSlice": {1, 1}, + "syscall.StringBytePtr": {1, 1}, + "syscall.StringSlicePtr": {1, 1}, + "syscall.StringToUTF16": {1, 1}, + "syscall.StringToUTF16Ptr": {1, 1}, +} diff --git a/vendor/honnef.co/go/tools/functions/concrete.go b/vendor/honnef.co/go/tools/functions/concrete.go new file mode 100644 index 0000000000..932acd03ed --- /dev/null +++ b/vendor/honnef.co/go/tools/functions/concrete.go @@ -0,0 +1,56 @@ +package functions + +import ( + "go/token" + "go/types" + + "honnef.co/go/tools/ssa" +) + +func concreteReturnTypes(fn *ssa.Function) []*types.Tuple { + res := fn.Signature.Results() + if res == nil { + return nil + } + ifaces := make([]bool, res.Len()) + any := false + for i := 0; i < res.Len(); i++ { + _, ifaces[i] = res.At(i).Type().Underlying().(*types.Interface) + any = any || ifaces[i] + } + if !any { + return []*types.Tuple{res} + } + var out []*types.Tuple + for _, block := range fn.Blocks { + if len(block.Instrs) == 0 { + continue + } + ret, ok := block.Instrs[len(block.Instrs)-1].(*ssa.Return) + if !ok { + continue + } + vars := make([]*types.Var, res.Len()) + for i, v := range ret.Results { + var typ types.Type + if !ifaces[i] { + typ = res.At(i).Type() + } else if mi, ok := v.(*ssa.MakeInterface); ok { + // TODO(dh): if mi.X is a function call that returns + // an interface, call concreteReturnTypes on that + // function (or, really, go through Descriptions, + // avoid infinite recursion etc, just like nil error + // detection) + + // TODO(dh): support Phi nodes + typ = mi.X.Type() + } else { + typ = res.At(i).Type() + } + vars[i] = types.NewParam(token.NoPos, nil, "", typ) + } + out = append(out, types.NewTuple(vars...)) + } + // TODO(dh): deduplicate out + return out +} diff --git a/vendor/honnef.co/go/tools/functions/functions.go b/vendor/honnef.co/go/tools/functions/functions.go new file mode 100644 index 0000000000..8394041297 --- /dev/null +++ b/vendor/honnef.co/go/tools/functions/functions.go @@ -0,0 +1,150 @@ +package functions + +import ( + "go/types" + "sync" + + "honnef.co/go/tools/callgraph" + "honnef.co/go/tools/callgraph/static" + "honnef.co/go/tools/ssa" + "honnef.co/go/tools/staticcheck/vrp" +) + +var stdlibDescs = map[string]Description{ + "errors.New": {Pure: true}, + + "fmt.Errorf": {Pure: true}, + "fmt.Sprintf": {Pure: true}, + "fmt.Sprint": {Pure: true}, + + "sort.Reverse": {Pure: true}, + + "strings.Map": {Pure: true}, + "strings.Repeat": {Pure: true}, + "strings.Replace": {Pure: true}, + "strings.Title": {Pure: true}, + "strings.ToLower": {Pure: true}, + "strings.ToLowerSpecial": {Pure: true}, + "strings.ToTitle": {Pure: true}, + "strings.ToTitleSpecial": {Pure: true}, + "strings.ToUpper": {Pure: true}, + "strings.ToUpperSpecial": {Pure: true}, + "strings.Trim": {Pure: true}, + "strings.TrimFunc": {Pure: true}, + "strings.TrimLeft": {Pure: true}, + "strings.TrimLeftFunc": {Pure: true}, + "strings.TrimPrefix": {Pure: true}, + "strings.TrimRight": {Pure: true}, + "strings.TrimRightFunc": {Pure: true}, + "strings.TrimSpace": {Pure: true}, + "strings.TrimSuffix": {Pure: true}, + + "(*net/http.Request).WithContext": {Pure: true}, + + "math/rand.Read": {NilError: true}, + "(*math/rand.Rand).Read": {NilError: true}, +} + +type Description struct { + // The function is known to be pure + Pure bool + // The function is known to be a stub + Stub bool + // The function is known to never return (panics notwithstanding) + Infinite bool + // Variable ranges + Ranges vrp.Ranges + Loops []Loop + // Function returns an error as its last argument, but it is + // always nil + NilError bool + ConcreteReturnTypes []*types.Tuple +} + +type descriptionEntry struct { + ready chan struct{} + result Description +} + +type Descriptions struct { + CallGraph *callgraph.Graph + mu sync.Mutex + cache map[*ssa.Function]*descriptionEntry +} + +func NewDescriptions(prog *ssa.Program) *Descriptions { + return &Descriptions{ + CallGraph: static.CallGraph(prog), + cache: map[*ssa.Function]*descriptionEntry{}, + } +} + +func (d *Descriptions) Get(fn *ssa.Function) Description { + d.mu.Lock() + fd := d.cache[fn] + if fd == nil { + fd = &descriptionEntry{ + ready: make(chan struct{}), + } + d.cache[fn] = fd + d.mu.Unlock() + + { + fd.result = stdlibDescs[fn.RelString(nil)] + fd.result.Pure = fd.result.Pure || d.IsPure(fn) + fd.result.Stub = fd.result.Stub || d.IsStub(fn) + fd.result.Infinite = fd.result.Infinite || !terminates(fn) + fd.result.Ranges = vrp.BuildGraph(fn).Solve() + fd.result.Loops = findLoops(fn) + fd.result.NilError = fd.result.NilError || IsNilError(fn) + fd.result.ConcreteReturnTypes = concreteReturnTypes(fn) + } + + close(fd.ready) + } else { + d.mu.Unlock() + <-fd.ready + } + return fd.result +} + +func IsNilError(fn *ssa.Function) bool { + // TODO(dh): This is very simplistic, as we only look for constant + // nil returns. A more advanced approach would work transitively. + // An even more advanced approach would be context-aware and + // determine nil errors based on inputs (e.g. io.WriteString to a + // bytes.Buffer will always return nil, but an io.WriteString to + // an os.File might not). Similarly, an os.File opened for reading + // won't error on Close, but other files will. + res := fn.Signature.Results() + if res.Len() == 0 { + return false + } + last := res.At(res.Len() - 1) + if types.TypeString(last.Type(), nil) != "error" { + return false + } + + if fn.Blocks == nil { + return false + } + for _, block := range fn.Blocks { + if len(block.Instrs) == 0 { + continue + } + ins := block.Instrs[len(block.Instrs)-1] + ret, ok := ins.(*ssa.Return) + if !ok { + continue + } + v := ret.Results[len(ret.Results)-1] + c, ok := v.(*ssa.Const) + if !ok { + return false + } + if !c.IsNil() { + return false + } + } + return true +} diff --git a/vendor/honnef.co/go/tools/functions/loops.go b/vendor/honnef.co/go/tools/functions/loops.go new file mode 100644 index 0000000000..63011cf3ef --- /dev/null +++ b/vendor/honnef.co/go/tools/functions/loops.go @@ -0,0 +1,50 @@ +package functions + +import "honnef.co/go/tools/ssa" + +type Loop map[*ssa.BasicBlock]bool + +func findLoops(fn *ssa.Function) []Loop { + if fn.Blocks == nil { + return nil + } + tree := fn.DomPreorder() + var sets []Loop + for _, h := range tree { + for _, n := range h.Preds { + if !h.Dominates(n) { + continue + } + // n is a back-edge to h + // h is the loop header + if n == h { + sets = append(sets, Loop{n: true}) + continue + } + set := Loop{h: true, n: true} + for _, b := range allPredsBut(n, h, nil) { + set[b] = true + } + sets = append(sets, set) + } + } + return sets +} + +func allPredsBut(b, but *ssa.BasicBlock, list []*ssa.BasicBlock) []*ssa.BasicBlock { +outer: + for _, pred := range b.Preds { + if pred == but { + continue + } + for _, p := range list { + // TODO improve big-o complexity of this function + if pred == p { + continue outer + } + } + list = append(list, pred) + list = allPredsBut(pred, but, list) + } + return list +} diff --git a/vendor/honnef.co/go/tools/functions/pure.go b/vendor/honnef.co/go/tools/functions/pure.go new file mode 100644 index 0000000000..7028eb8c64 --- /dev/null +++ b/vendor/honnef.co/go/tools/functions/pure.go @@ -0,0 +1,123 @@ +package functions + +import ( + "go/token" + "go/types" + + "honnef.co/go/tools/callgraph" + "honnef.co/go/tools/lint/lintdsl" + "honnef.co/go/tools/ssa" +) + +// IsStub reports whether a function is a stub. A function is +// considered a stub if it has no instructions or exactly one +// instruction, which must be either returning only constant values or +// a panic. +func (d *Descriptions) IsStub(fn *ssa.Function) bool { + if len(fn.Blocks) == 0 { + return true + } + if len(fn.Blocks) > 1 { + return false + } + instrs := lintdsl.FilterDebug(fn.Blocks[0].Instrs) + if len(instrs) != 1 { + return false + } + + switch instrs[0].(type) { + case *ssa.Return: + // Since this is the only instruction, the return value must + // be a constant. We consider all constants as stubs, not just + // the zero value. This does not, unfortunately, cover zero + // initialised structs, as these cause additional + // instructions. + return true + case *ssa.Panic: + return true + default: + return false + } +} + +func (d *Descriptions) IsPure(fn *ssa.Function) bool { + if fn.Signature.Results().Len() == 0 { + // A function with no return values is empty or is doing some + // work we cannot see (for example because of build tags); + // don't consider it pure. + return false + } + + for _, param := range fn.Params { + if _, ok := param.Type().Underlying().(*types.Basic); !ok { + return false + } + } + + if fn.Blocks == nil { + return false + } + checkCall := func(common *ssa.CallCommon) bool { + if common.IsInvoke() { + return false + } + builtin, ok := common.Value.(*ssa.Builtin) + if !ok { + if common.StaticCallee() != fn { + if common.StaticCallee() == nil { + return false + } + // TODO(dh): ideally, IsPure wouldn't be responsible + // for avoiding infinite recursion, but + // FunctionDescriptions would be. + node := d.CallGraph.CreateNode(common.StaticCallee()) + if callgraph.PathSearch(node, func(other *callgraph.Node) bool { + return other.Func == fn + }) != nil { + return false + } + if !d.Get(common.StaticCallee()).Pure { + return false + } + } + } else { + switch builtin.Name() { + case "len", "cap", "make", "new": + default: + return false + } + } + return true + } + for _, b := range fn.Blocks { + for _, ins := range b.Instrs { + switch ins := ins.(type) { + case *ssa.Call: + if !checkCall(ins.Common()) { + return false + } + case *ssa.Defer: + if !checkCall(&ins.Call) { + return false + } + case *ssa.Select: + return false + case *ssa.Send: + return false + case *ssa.Go: + return false + case *ssa.Panic: + return false + case *ssa.Store: + return false + case *ssa.FieldAddr: + return false + case *ssa.UnOp: + if ins.Op == token.MUL || ins.Op == token.AND { + return false + } + } + } + } + return true +} diff --git a/vendor/honnef.co/go/tools/functions/terminates.go b/vendor/honnef.co/go/tools/functions/terminates.go new file mode 100644 index 0000000000..65f9e16dc9 --- /dev/null +++ b/vendor/honnef.co/go/tools/functions/terminates.go @@ -0,0 +1,24 @@ +package functions + +import "honnef.co/go/tools/ssa" + +// terminates reports whether fn is supposed to return, that is if it +// has at least one theoretic path that returns from the function. +// Explicit panics do not count as terminating. +func terminates(fn *ssa.Function) bool { + if fn.Blocks == nil { + // assuming that a function terminates is the conservative + // choice + return true + } + + for _, block := range fn.Blocks { + if len(block.Instrs) == 0 { + continue + } + if _, ok := block.Instrs[len(block.Instrs)-1].(*ssa.Return); ok { + return true + } + } + return false +} diff --git a/vendor/honnef.co/go/tools/internal/sharedcheck/lint.go b/vendor/honnef.co/go/tools/internal/sharedcheck/lint.go new file mode 100644 index 0000000000..cbbafbcdf4 --- /dev/null +++ b/vendor/honnef.co/go/tools/internal/sharedcheck/lint.go @@ -0,0 +1,68 @@ +package sharedcheck + +import ( + "go/ast" + "go/types" + + "honnef.co/go/tools/lint" + . "honnef.co/go/tools/lint/lintdsl" + "honnef.co/go/tools/ssa" +) + +func CheckRangeStringRunes(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + fn := func(node ast.Node) bool { + rng, ok := node.(*ast.RangeStmt) + if !ok || !IsBlank(rng.Key) { + return true + } + + v, _ := ssafn.ValueForExpr(rng.X) + + // Check that we're converting from string to []rune + val, _ := v.(*ssa.Convert) + if val == nil { + return true + } + Tsrc, ok := val.X.Type().(*types.Basic) + if !ok || Tsrc.Kind() != types.String { + return true + } + Tdst, ok := val.Type().(*types.Slice) + if !ok { + return true + } + TdstElem, ok := Tdst.Elem().(*types.Basic) + if !ok || TdstElem.Kind() != types.Int32 { + return true + } + + // Check that the result of the conversion is only used to + // range over + refs := val.Referrers() + if refs == nil { + return true + } + + // Expect two refs: one for obtaining the length of the slice, + // one for accessing the elements + if len(FilterDebug(*refs)) != 2 { + // TODO(dh): right now, we check that only one place + // refers to our slice. This will miss cases such as + // ranging over the slice twice. Ideally, we'd ensure that + // the slice is only used for ranging over (without + // accessing the key), but that is harder to do because in + // SSA form, ranging over a slice looks like an ordinary + // loop with index increments and slice accesses. We'd + // have to look at the associated AST node to check that + // it's a range statement. + return true + } + + j.Errorf(rng, "should range over string, not []rune(string)") + + return true + } + Inspect(ssafn.Syntax(), fn) + } +} diff --git a/vendor/honnef.co/go/tools/lint/LICENSE b/vendor/honnef.co/go/tools/lint/LICENSE new file mode 100644 index 0000000000..796130a123 --- /dev/null +++ b/vendor/honnef.co/go/tools/lint/LICENSE @@ -0,0 +1,28 @@ +Copyright (c) 2013 The Go Authors. All rights reserved. +Copyright (c) 2016 Dominik Honnef. All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + * Redistributions of source code must retain the above copyright +notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above +copyright notice, this list of conditions and the following disclaimer +in the documentation and/or other materials provided with the +distribution. + * Neither the name of Google Inc. nor the names of its +contributors may be used to endorse or promote products derived from +this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/vendor/honnef.co/go/tools/lint/generated.go b/vendor/honnef.co/go/tools/lint/generated.go new file mode 100644 index 0000000000..d407223e78 --- /dev/null +++ b/vendor/honnef.co/go/tools/lint/generated.go @@ -0,0 +1,33 @@ +package lint + +import ( + "bufio" + "bytes" + "io" +) + +var ( + prefix = []byte("// Code generated ") + suffix = []byte(" DO NOT EDIT.") + nl = []byte("\n") + crnl = []byte("\r\n") +) + +func isGenerated(r io.Reader) bool { + br := bufio.NewReader(r) + for { + s, err := br.ReadBytes('\n') + if err != nil && err != io.EOF { + return false + } + s = bytes.TrimSuffix(s, crnl) + s = bytes.TrimSuffix(s, nl) + if bytes.HasPrefix(s, prefix) && bytes.HasSuffix(s, suffix) { + return true + } + if err == io.EOF { + break + } + } + return false +} diff --git a/vendor/honnef.co/go/tools/lint/lint.go b/vendor/honnef.co/go/tools/lint/lint.go new file mode 100644 index 0000000000..27fdda3495 --- /dev/null +++ b/vendor/honnef.co/go/tools/lint/lint.go @@ -0,0 +1,716 @@ +// Package lint provides the foundation for tools like staticcheck +package lint // import "honnef.co/go/tools/lint" + +import ( + "fmt" + "go/ast" + "go/token" + "go/types" + "io" + "os" + "path/filepath" + "sort" + "strings" + "sync" + "time" + "unicode" + + "golang.org/x/tools/go/packages" + "honnef.co/go/tools/config" + "honnef.co/go/tools/ssa" + "honnef.co/go/tools/ssa/ssautil" +) + +type Job struct { + Program *Program + + checker string + check Check + problems []Problem + + duration time.Duration +} + +type Ignore interface { + Match(p Problem) bool +} + +type LineIgnore struct { + File string + Line int + Checks []string + matched bool + pos token.Pos +} + +func (li *LineIgnore) Match(p Problem) bool { + if p.Position.Filename != li.File || p.Position.Line != li.Line { + return false + } + for _, c := range li.Checks { + if m, _ := filepath.Match(c, p.Check); m { + li.matched = true + return true + } + } + return false +} + +func (li *LineIgnore) String() string { + matched := "not matched" + if li.matched { + matched = "matched" + } + return fmt.Sprintf("%s:%d %s (%s)", li.File, li.Line, strings.Join(li.Checks, ", "), matched) +} + +type FileIgnore struct { + File string + Checks []string +} + +func (fi *FileIgnore) Match(p Problem) bool { + if p.Position.Filename != fi.File { + return false + } + for _, c := range fi.Checks { + if m, _ := filepath.Match(c, p.Check); m { + return true + } + } + return false +} + +type GlobIgnore struct { + Pattern string + Checks []string +} + +func (gi *GlobIgnore) Match(p Problem) bool { + if gi.Pattern != "*" { + pkgpath := p.Package.Types.Path() + if strings.HasSuffix(pkgpath, "_test") { + pkgpath = pkgpath[:len(pkgpath)-len("_test")] + } + name := filepath.Join(pkgpath, filepath.Base(p.Position.Filename)) + if m, _ := filepath.Match(gi.Pattern, name); !m { + return false + } + } + for _, c := range gi.Checks { + if m, _ := filepath.Match(c, p.Check); m { + return true + } + } + return false +} + +type Program struct { + SSA *ssa.Program + InitialPackages []*Pkg + InitialFunctions []*ssa.Function + AllPackages []*packages.Package + AllFunctions []*ssa.Function + Files []*ast.File + GoVersion int + + tokenFileMap map[*token.File]*ast.File + astFileMap map[*ast.File]*Pkg + packagesMap map[string]*packages.Package + + genMu sync.RWMutex + generatedMap map[string]bool +} + +func (prog *Program) Fset() *token.FileSet { + return prog.InitialPackages[0].Fset +} + +type Func func(*Job) + +type Severity uint8 + +const ( + Error Severity = iota + Warning + Ignored +) + +// Problem represents a problem in some source code. +type Problem struct { + Position token.Position // position in source file + Text string // the prose that describes the problem + Check string + Checker string + Package *Pkg + Severity Severity +} + +func (p *Problem) String() string { + if p.Check == "" { + return p.Text + } + return fmt.Sprintf("%s (%s)", p.Text, p.Check) +} + +type Checker interface { + Name() string + Prefix() string + Init(*Program) + Checks() []Check +} + +type Check struct { + Fn Func + ID string + FilterGenerated bool +} + +// A Linter lints Go source code. +type Linter struct { + Checkers []Checker + Ignores []Ignore + GoVersion int + ReturnIgnored bool + Config config.Config + + MaxConcurrentJobs int + PrintStats bool + + automaticIgnores []Ignore +} + +func (l *Linter) ignore(p Problem) bool { + ignored := false + for _, ig := range l.automaticIgnores { + // We cannot short-circuit these, as we want to record, for + // each ignore, whether it matched or not. + if ig.Match(p) { + ignored = true + } + } + if ignored { + // no need to execute other ignores if we've already had a + // match. + return true + } + for _, ig := range l.Ignores { + // We can short-circuit here, as we aren't tracking any + // information. + if ig.Match(p) { + return true + } + } + + return false +} + +func (prog *Program) File(node Positioner) *ast.File { + return prog.tokenFileMap[prog.SSA.Fset.File(node.Pos())] +} + +func (j *Job) File(node Positioner) *ast.File { + return j.Program.File(node) +} + +func parseDirective(s string) (cmd string, args []string) { + if !strings.HasPrefix(s, "//lint:") { + return "", nil + } + s = strings.TrimPrefix(s, "//lint:") + fields := strings.Split(s, " ") + return fields[0], fields[1:] +} + +type PerfStats struct { + PackageLoading time.Duration + SSABuild time.Duration + OtherInitWork time.Duration + CheckerInits map[string]time.Duration + Jobs []JobStat +} + +type JobStat struct { + Job string + Duration time.Duration +} + +func (stats *PerfStats) Print(w io.Writer) { + fmt.Fprintln(w, "Package loading:", stats.PackageLoading) + fmt.Fprintln(w, "SSA build:", stats.SSABuild) + fmt.Fprintln(w, "Other init work:", stats.OtherInitWork) + + fmt.Fprintln(w, "Checker inits:") + for checker, d := range stats.CheckerInits { + fmt.Fprintf(w, "\t%s: %s\n", checker, d) + } + fmt.Fprintln(w) + + fmt.Fprintln(w, "Jobs:") + sort.Slice(stats.Jobs, func(i, j int) bool { + return stats.Jobs[i].Duration < stats.Jobs[j].Duration + }) + var total time.Duration + for _, job := range stats.Jobs { + fmt.Fprintf(w, "\t%s: %s\n", job.Job, job.Duration) + total += job.Duration + } + fmt.Fprintf(w, "\tTotal: %s\n", total) +} + +func (l *Linter) Lint(initial []*packages.Package, stats *PerfStats) []Problem { + allPkgs := allPackages(initial) + t := time.Now() + ssaprog, _ := ssautil.Packages(allPkgs, ssa.GlobalDebug) + ssaprog.Build() + if stats != nil { + stats.SSABuild = time.Since(t) + } + + t = time.Now() + pkgMap := map[*ssa.Package]*Pkg{} + var pkgs []*Pkg + for _, pkg := range initial { + ssapkg := ssaprog.Package(pkg.Types) + var cfg config.Config + if len(pkg.GoFiles) != 0 { + path := pkg.GoFiles[0] + dir := filepath.Dir(path) + var err error + // OPT(dh): we're rebuilding the entire config tree for + // each package. for example, if we check a/b/c and + // a/b/c/d, we'll process a, a/b, a/b/c, a, a/b, a/b/c, + // a/b/c/d – we should cache configs per package and only + // load the new levels. + cfg, err = config.Load(dir) + if err != nil { + // FIXME(dh): we couldn't load the config, what are we + // supposed to do? probably tell the user somehow + } + cfg = cfg.Merge(l.Config) + } + + pkg := &Pkg{ + SSA: ssapkg, + Package: pkg, + Config: cfg, + } + pkgMap[ssapkg] = pkg + pkgs = append(pkgs, pkg) + } + + prog := &Program{ + SSA: ssaprog, + InitialPackages: pkgs, + AllPackages: allPkgs, + GoVersion: l.GoVersion, + tokenFileMap: map[*token.File]*ast.File{}, + astFileMap: map[*ast.File]*Pkg{}, + generatedMap: map[string]bool{}, + } + prog.packagesMap = map[string]*packages.Package{} + for _, pkg := range allPkgs { + prog.packagesMap[pkg.Types.Path()] = pkg + } + + isInitial := map[*types.Package]struct{}{} + for _, pkg := range pkgs { + isInitial[pkg.Types] = struct{}{} + } + for fn := range ssautil.AllFunctions(ssaprog) { + if fn.Pkg == nil { + continue + } + prog.AllFunctions = append(prog.AllFunctions, fn) + if _, ok := isInitial[fn.Pkg.Pkg]; ok { + prog.InitialFunctions = append(prog.InitialFunctions, fn) + } + } + for _, pkg := range pkgs { + prog.Files = append(prog.Files, pkg.Syntax...) + + ssapkg := ssaprog.Package(pkg.Types) + for _, f := range pkg.Syntax { + prog.astFileMap[f] = pkgMap[ssapkg] + } + } + + for _, pkg := range allPkgs { + for _, f := range pkg.Syntax { + tf := pkg.Fset.File(f.Pos()) + prog.tokenFileMap[tf] = f + } + } + + var out []Problem + l.automaticIgnores = nil + for _, pkg := range initial { + for _, f := range pkg.Syntax { + cm := ast.NewCommentMap(pkg.Fset, f, f.Comments) + for node, cgs := range cm { + for _, cg := range cgs { + for _, c := range cg.List { + if !strings.HasPrefix(c.Text, "//lint:") { + continue + } + cmd, args := parseDirective(c.Text) + switch cmd { + case "ignore", "file-ignore": + if len(args) < 2 { + // FIXME(dh): this causes duplicated warnings when using megacheck + p := Problem{ + Position: prog.DisplayPosition(c.Pos()), + Text: "malformed linter directive; missing the required reason field?", + Check: "", + Checker: "lint", + Package: nil, + } + out = append(out, p) + continue + } + default: + // unknown directive, ignore + continue + } + checks := strings.Split(args[0], ",") + pos := prog.DisplayPosition(node.Pos()) + var ig Ignore + switch cmd { + case "ignore": + ig = &LineIgnore{ + File: pos.Filename, + Line: pos.Line, + Checks: checks, + pos: c.Pos(), + } + case "file-ignore": + ig = &FileIgnore{ + File: pos.Filename, + Checks: checks, + } + } + l.automaticIgnores = append(l.automaticIgnores, ig) + } + } + } + } + } + + sizes := struct { + types int + defs int + uses int + implicits int + selections int + scopes int + }{} + for _, pkg := range pkgs { + sizes.types += len(pkg.TypesInfo.Types) + sizes.defs += len(pkg.TypesInfo.Defs) + sizes.uses += len(pkg.TypesInfo.Uses) + sizes.implicits += len(pkg.TypesInfo.Implicits) + sizes.selections += len(pkg.TypesInfo.Selections) + sizes.scopes += len(pkg.TypesInfo.Scopes) + } + + if stats != nil { + stats.OtherInitWork = time.Since(t) + } + + for _, checker := range l.Checkers { + t := time.Now() + checker.Init(prog) + if stats != nil { + stats.CheckerInits[checker.Name()] = time.Since(t) + } + } + + var jobs []*Job + var allChecks []string + + for _, checker := range l.Checkers { + checks := checker.Checks() + for _, check := range checks { + allChecks = append(allChecks, check.ID) + j := &Job{ + Program: prog, + checker: checker.Name(), + check: check, + } + jobs = append(jobs, j) + } + } + + max := len(jobs) + if l.MaxConcurrentJobs > 0 { + max = l.MaxConcurrentJobs + } + + sem := make(chan struct{}, max) + wg := &sync.WaitGroup{} + for _, j := range jobs { + wg.Add(1) + go func(j *Job) { + defer wg.Done() + sem <- struct{}{} + defer func() { <-sem }() + fn := j.check.Fn + if fn == nil { + return + } + t := time.Now() + fn(j) + j.duration = time.Since(t) + }(j) + } + wg.Wait() + + for _, j := range jobs { + if stats != nil { + stats.Jobs = append(stats.Jobs, JobStat{j.check.ID, j.duration}) + } + for _, p := range j.problems { + allowedChecks := FilterChecks(allChecks, p.Package.Config.Checks) + + if l.ignore(p) { + p.Severity = Ignored + } + // TODO(dh): support globs in check white/blacklist + // OPT(dh): this approach doesn't actually disable checks, + // it just discards their results. For the moment, that's + // fine. None of our checks are super expensive. In the + // future, we may want to provide opt-in expensive + // analysis, which shouldn't run at all. It may be easiest + // to implement this in the individual checks. + if (l.ReturnIgnored || p.Severity != Ignored) && allowedChecks[p.Check] { + out = append(out, p) + } + } + } + + for _, ig := range l.automaticIgnores { + ig, ok := ig.(*LineIgnore) + if !ok { + continue + } + if ig.matched { + continue + } + + couldveMatched := false + for f, pkg := range prog.astFileMap { + if prog.Fset().Position(f.Pos()).Filename != ig.File { + continue + } + allowedChecks := FilterChecks(allChecks, pkg.Config.Checks) + for _, c := range ig.Checks { + if !allowedChecks[c] { + continue + } + couldveMatched = true + break + } + break + } + + if !couldveMatched { + // The ignored checks were disabled for the containing package. + // Don't flag the ignore for not having matched. + continue + } + p := Problem{ + Position: prog.DisplayPosition(ig.pos), + Text: "this linter directive didn't match anything; should it be removed?", + Check: "", + Checker: "lint", + Package: nil, + } + out = append(out, p) + } + + sort.Slice(out, func(i int, j int) bool { + pi, pj := out[i].Position, out[j].Position + + if pi.Filename != pj.Filename { + return pi.Filename < pj.Filename + } + if pi.Line != pj.Line { + return pi.Line < pj.Line + } + if pi.Column != pj.Column { + return pi.Column < pj.Column + } + + return out[i].Text < out[j].Text + }) + + if len(out) < 2 { + return out + } + + uniq := make([]Problem, 0, len(out)) + uniq = append(uniq, out[0]) + prev := out[0] + for _, p := range out[1:] { + if prev.Position == p.Position && prev.Text == p.Text { + continue + } + prev = p + uniq = append(uniq, p) + } + + if l.PrintStats && stats != nil { + stats.Print(os.Stderr) + } + return uniq +} + +func FilterChecks(allChecks []string, checks []string) map[string]bool { + // OPT(dh): this entire computation could be cached per package + allowedChecks := map[string]bool{} + + for _, check := range checks { + b := true + if len(check) > 1 && check[0] == '-' { + b = false + check = check[1:] + } + if check == "*" || check == "all" { + // Match all + for _, c := range allChecks { + allowedChecks[c] = b + } + } else if strings.HasSuffix(check, "*") { + // Glob + prefix := check[:len(check)-1] + isCat := strings.IndexFunc(prefix, func(r rune) bool { return unicode.IsNumber(r) }) == -1 + + for _, c := range allChecks { + idx := strings.IndexFunc(c, func(r rune) bool { return unicode.IsNumber(r) }) + if isCat { + // Glob is S*, which should match S1000 but not SA1000 + cat := c[:idx] + if prefix == cat { + allowedChecks[c] = b + } + } else { + // Glob is S1* + if strings.HasPrefix(c, prefix) { + allowedChecks[c] = b + } + } + } + } else { + // Literal check name + allowedChecks[check] = b + } + } + return allowedChecks +} + +func (prog *Program) Package(path string) *packages.Package { + return prog.packagesMap[path] +} + +// Pkg represents a package being linted. +type Pkg struct { + SSA *ssa.Package + *packages.Package + Config config.Config +} + +type Positioner interface { + Pos() token.Pos +} + +func (prog *Program) DisplayPosition(p token.Pos) token.Position { + // Only use the adjusted position if it points to another Go file. + // This means we'll point to the original file for cgo files, but + // we won't point to a YACC grammar file. + + pos := prog.Fset().PositionFor(p, false) + adjPos := prog.Fset().PositionFor(p, true) + + if filepath.Ext(adjPos.Filename) == ".go" { + return adjPos + } + return pos +} + +func (prog *Program) isGenerated(path string) bool { + // This function isn't very efficient in terms of lock contention + // and lack of parallelism, but it really shouldn't matter. + // Projects consists of thousands of files, and have hundreds of + // errors. That's not a lot of calls to isGenerated. + + prog.genMu.RLock() + if b, ok := prog.generatedMap[path]; ok { + prog.genMu.RUnlock() + return b + } + prog.genMu.RUnlock() + prog.genMu.Lock() + defer prog.genMu.Unlock() + // recheck to avoid doing extra work in case of race + if b, ok := prog.generatedMap[path]; ok { + return b + } + + f, err := os.Open(path) + if err != nil { + return false + } + defer f.Close() + b := isGenerated(f) + prog.generatedMap[path] = b + return b +} + +func (j *Job) Errorf(n Positioner, format string, args ...interface{}) *Problem { + tf := j.Program.SSA.Fset.File(n.Pos()) + f := j.Program.tokenFileMap[tf] + pkg := j.Program.astFileMap[f] + + pos := j.Program.DisplayPosition(n.Pos()) + if j.Program.isGenerated(pos.Filename) && j.check.FilterGenerated { + return nil + } + problem := Problem{ + Position: pos, + Text: fmt.Sprintf(format, args...), + Check: j.check.ID, + Checker: j.checker, + Package: pkg, + } + j.problems = append(j.problems, problem) + return &j.problems[len(j.problems)-1] +} + +func (j *Job) NodePackage(node Positioner) *Pkg { + f := j.File(node) + return j.Program.astFileMap[f] +} + +// TODO(dh): replace with packages.Visit +func allPackages(pkgs []*packages.Package) []*packages.Package { + all := map[*packages.Package]bool{} + var wl []*packages.Package + wl = append(wl, pkgs...) + for len(wl) > 0 { + pkg := wl[len(wl)-1] + wl = wl[:len(wl)-1] + if all[pkg] { + continue + } + all[pkg] = true + for _, imp := range pkg.Imports { + wl = append(wl, imp) + } + } + + out := make([]*packages.Package, 0, len(all)) + for pkg := range all { + out = append(out, pkg) + } + return out +} diff --git a/vendor/honnef.co/go/tools/lint/lintdsl/lintdsl.go b/vendor/honnef.co/go/tools/lint/lintdsl/lintdsl.go new file mode 100644 index 0000000000..64f3338e99 --- /dev/null +++ b/vendor/honnef.co/go/tools/lint/lintdsl/lintdsl.go @@ -0,0 +1,301 @@ +// Package lintdsl provides helpers for implementing static analysis +// checks. Dot-importing this package is encouraged. +package lintdsl + +import ( + "bytes" + "fmt" + "go/ast" + "go/constant" + "go/printer" + "go/token" + "go/types" + "strings" + + "honnef.co/go/tools/lint" + "honnef.co/go/tools/ssa" +) + +type packager interface { + Package() *ssa.Package +} + +func CallName(call *ssa.CallCommon) string { + if call.IsInvoke() { + return "" + } + switch v := call.Value.(type) { + case *ssa.Function: + fn, ok := v.Object().(*types.Func) + if !ok { + return "" + } + return fn.FullName() + case *ssa.Builtin: + return v.Name() + } + return "" +} + +func IsCallTo(call *ssa.CallCommon, name string) bool { return CallName(call) == name } +func IsType(T types.Type, name string) bool { return types.TypeString(T, nil) == name } + +func FilterDebug(instr []ssa.Instruction) []ssa.Instruction { + var out []ssa.Instruction + for _, ins := range instr { + if _, ok := ins.(*ssa.DebugRef); !ok { + out = append(out, ins) + } + } + return out +} + +func IsExample(fn *ssa.Function) bool { + if !strings.HasPrefix(fn.Name(), "Example") { + return false + } + f := fn.Prog.Fset.File(fn.Pos()) + if f == nil { + return false + } + return strings.HasSuffix(f.Name(), "_test.go") +} + +func IsPointerLike(T types.Type) bool { + switch T := T.Underlying().(type) { + case *types.Interface, *types.Chan, *types.Map, *types.Pointer: + return true + case *types.Basic: + return T.Kind() == types.UnsafePointer + } + return false +} + +func IsGenerated(f *ast.File) bool { + comments := f.Comments + if len(comments) > 0 { + comment := comments[0].Text() + return strings.Contains(comment, "Code generated by") || + strings.Contains(comment, "DO NOT EDIT") + } + return false +} + +func IsIdent(expr ast.Expr, ident string) bool { + id, ok := expr.(*ast.Ident) + return ok && id.Name == ident +} + +// isBlank returns whether id is the blank identifier "_". +// If id == nil, the answer is false. +func IsBlank(id ast.Expr) bool { + ident, _ := id.(*ast.Ident) + return ident != nil && ident.Name == "_" +} + +func IsIntLiteral(expr ast.Expr, literal string) bool { + lit, ok := expr.(*ast.BasicLit) + return ok && lit.Kind == token.INT && lit.Value == literal +} + +// Deprecated: use IsIntLiteral instead +func IsZero(expr ast.Expr) bool { + return IsIntLiteral(expr, "0") +} + +func TypeOf(j *lint.Job, expr ast.Expr) types.Type { + if expr == nil { + return nil + } + return j.NodePackage(expr).TypesInfo.TypeOf(expr) +} + +func IsOfType(j *lint.Job, expr ast.Expr, name string) bool { return IsType(TypeOf(j, expr), name) } + +func ObjectOf(j *lint.Job, ident *ast.Ident) types.Object { + if ident == nil { + return nil + } + return j.NodePackage(ident).TypesInfo.ObjectOf(ident) +} + +func IsInTest(j *lint.Job, node lint.Positioner) bool { + // FIXME(dh): this doesn't work for global variables with + // initializers + f := j.Program.SSA.Fset.File(node.Pos()) + return f != nil && strings.HasSuffix(f.Name(), "_test.go") +} + +func IsInMain(j *lint.Job, node lint.Positioner) bool { + if node, ok := node.(packager); ok { + return node.Package().Pkg.Name() == "main" + } + pkg := j.NodePackage(node) + if pkg == nil { + return false + } + return pkg.Types.Name() == "main" +} + +func SelectorName(j *lint.Job, expr *ast.SelectorExpr) string { + info := j.NodePackage(expr).TypesInfo + sel := info.Selections[expr] + if sel == nil { + if x, ok := expr.X.(*ast.Ident); ok { + pkg, ok := info.ObjectOf(x).(*types.PkgName) + if !ok { + // This shouldn't happen + return fmt.Sprintf("%s.%s", x.Name, expr.Sel.Name) + } + return fmt.Sprintf("%s.%s", pkg.Imported().Path(), expr.Sel.Name) + } + panic(fmt.Sprintf("unsupported selector: %v", expr)) + } + return fmt.Sprintf("(%s).%s", sel.Recv(), sel.Obj().Name()) +} + +func IsNil(j *lint.Job, expr ast.Expr) bool { + return j.NodePackage(expr).TypesInfo.Types[expr].IsNil() +} + +func BoolConst(j *lint.Job, expr ast.Expr) bool { + val := j.NodePackage(expr).TypesInfo.ObjectOf(expr.(*ast.Ident)).(*types.Const).Val() + return constant.BoolVal(val) +} + +func IsBoolConst(j *lint.Job, expr ast.Expr) bool { + // We explicitly don't support typed bools because more often than + // not, custom bool types are used as binary enums and the + // explicit comparison is desired. + + ident, ok := expr.(*ast.Ident) + if !ok { + return false + } + obj := j.NodePackage(expr).TypesInfo.ObjectOf(ident) + c, ok := obj.(*types.Const) + if !ok { + return false + } + basic, ok := c.Type().(*types.Basic) + if !ok { + return false + } + if basic.Kind() != types.UntypedBool && basic.Kind() != types.Bool { + return false + } + return true +} + +func ExprToInt(j *lint.Job, expr ast.Expr) (int64, bool) { + tv := j.NodePackage(expr).TypesInfo.Types[expr] + if tv.Value == nil { + return 0, false + } + if tv.Value.Kind() != constant.Int { + return 0, false + } + return constant.Int64Val(tv.Value) +} + +func ExprToString(j *lint.Job, expr ast.Expr) (string, bool) { + val := j.NodePackage(expr).TypesInfo.Types[expr].Value + if val == nil { + return "", false + } + if val.Kind() != constant.String { + return "", false + } + return constant.StringVal(val), true +} + +// Dereference returns a pointer's element type; otherwise it returns +// T. +func Dereference(T types.Type) types.Type { + if p, ok := T.Underlying().(*types.Pointer); ok { + return p.Elem() + } + return T +} + +// DereferenceR returns a pointer's element type; otherwise it returns +// T. If the element type is itself a pointer, DereferenceR will be +// applied recursively. +func DereferenceR(T types.Type) types.Type { + if p, ok := T.Underlying().(*types.Pointer); ok { + return DereferenceR(p.Elem()) + } + return T +} + +func IsGoVersion(j *lint.Job, minor int) bool { + return j.Program.GoVersion >= minor +} + +func CallNameAST(j *lint.Job, call *ast.CallExpr) string { + sel, ok := call.Fun.(*ast.SelectorExpr) + if !ok { + return "" + } + fn, ok := j.NodePackage(call).TypesInfo.ObjectOf(sel.Sel).(*types.Func) + if !ok { + return "" + } + return fn.FullName() +} + +func IsCallToAST(j *lint.Job, node ast.Node, name string) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return false + } + return CallNameAST(j, call) == name +} + +func IsCallToAnyAST(j *lint.Job, node ast.Node, names ...string) bool { + for _, name := range names { + if IsCallToAST(j, node, name) { + return true + } + } + return false +} + +func Render(j *lint.Job, x interface{}) string { + fset := j.Program.SSA.Fset + var buf bytes.Buffer + if err := printer.Fprint(&buf, fset, x); err != nil { + panic(err) + } + return buf.String() +} + +func RenderArgs(j *lint.Job, args []ast.Expr) string { + var ss []string + for _, arg := range args { + ss = append(ss, Render(j, arg)) + } + return strings.Join(ss, ", ") +} + +func Preamble(f *ast.File) string { + cutoff := f.Package + if f.Doc != nil { + cutoff = f.Doc.Pos() + } + var out []string + for _, cmt := range f.Comments { + if cmt.Pos() >= cutoff { + break + } + out = append(out, cmt.Text()) + } + return strings.Join(out, "\n") +} + +func Inspect(node ast.Node, fn func(node ast.Node) bool) { + if node == nil { + return + } + ast.Inspect(node, fn) +} diff --git a/vendor/honnef.co/go/tools/lint/lintutil/format/format.go b/vendor/honnef.co/go/tools/lint/lintutil/format/format.go new file mode 100644 index 0000000000..d41ab4b672 --- /dev/null +++ b/vendor/honnef.co/go/tools/lint/lintutil/format/format.go @@ -0,0 +1,124 @@ +// Package format provides formatters for linter problems. +package format + +import ( + "encoding/json" + "fmt" + "go/token" + "io" + "os" + "path/filepath" + "text/tabwriter" + + "honnef.co/go/tools/lint" +) + +func shortPath(path string) string { + cwd, err := os.Getwd() + if err != nil { + return path + } + if rel, err := filepath.Rel(cwd, path); err == nil && len(rel) < len(path) { + return rel + } + return path +} + +func relativePositionString(pos token.Position) string { + s := shortPath(pos.Filename) + if pos.IsValid() { + if s != "" { + s += ":" + } + s += fmt.Sprintf("%d:%d", pos.Line, pos.Column) + } + if s == "" { + s = "-" + } + return s +} + +type Statter interface { + Stats(total, errors, warnings int) +} + +type Formatter interface { + Format(p lint.Problem) +} + +type Text struct { + W io.Writer +} + +func (o Text) Format(p lint.Problem) { + fmt.Fprintf(o.W, "%v: %s\n", relativePositionString(p.Position), p.String()) +} + +type JSON struct { + W io.Writer +} + +func severity(s lint.Severity) string { + switch s { + case lint.Error: + return "error" + case lint.Warning: + return "warning" + case lint.Ignored: + return "ignored" + } + return "" +} + +func (o JSON) Format(p lint.Problem) { + type location struct { + File string `json:"file"` + Line int `json:"line"` + Column int `json:"column"` + } + jp := struct { + Code string `json:"code"` + Severity string `json:"severity,omitempty"` + Location location `json:"location"` + Message string `json:"message"` + }{ + Code: p.Check, + Severity: severity(p.Severity), + Location: location{ + File: p.Position.Filename, + Line: p.Position.Line, + Column: p.Position.Column, + }, + Message: p.Text, + } + _ = json.NewEncoder(o.W).Encode(jp) +} + +type Stylish struct { + W io.Writer + + prevFile string + tw *tabwriter.Writer +} + +func (o *Stylish) Format(p lint.Problem) { + if p.Position.Filename != o.prevFile { + if o.prevFile != "" { + o.tw.Flush() + fmt.Fprintln(o.W) + } + fmt.Fprintln(o.W, p.Position.Filename) + o.prevFile = p.Position.Filename + o.tw = tabwriter.NewWriter(o.W, 0, 4, 2, ' ', 0) + } + fmt.Fprintf(o.tw, " (%d, %d)\t%s\t%s\n", p.Position.Line, p.Position.Column, p.Check, p.Text) +} + +func (o *Stylish) Stats(total, errors, warnings int) { + if o.tw != nil { + o.tw.Flush() + fmt.Fprintln(o.W) + } + fmt.Fprintf(o.W, " ✖ %d problems (%d errors, %d warnings)\n", + total, errors, warnings) +} diff --git a/vendor/honnef.co/go/tools/lint/lintutil/util.go b/vendor/honnef.co/go/tools/lint/lintutil/util.go new file mode 100644 index 0000000000..de343a2f3c --- /dev/null +++ b/vendor/honnef.co/go/tools/lint/lintutil/util.go @@ -0,0 +1,362 @@ +// Copyright (c) 2013 The Go Authors. All rights reserved. +// +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file or at +// https://developers.google.com/open-source/licenses/bsd. + +// Package lintutil provides helpers for writing linter command lines. +package lintutil // import "honnef.co/go/tools/lint/lintutil" + +import ( + "errors" + "flag" + "fmt" + "go/build" + "go/token" + "log" + "os" + "regexp" + "runtime" + "runtime/pprof" + "strconv" + "strings" + "time" + + "honnef.co/go/tools/config" + "honnef.co/go/tools/lint" + "honnef.co/go/tools/lint/lintutil/format" + "honnef.co/go/tools/version" + + "golang.org/x/tools/go/packages" +) + +func usage(name string, flags *flag.FlagSet) func() { + return func() { + fmt.Fprintf(os.Stderr, "Usage of %s:\n", name) + fmt.Fprintf(os.Stderr, "\t%s [flags] # runs on package in current directory\n", name) + fmt.Fprintf(os.Stderr, "\t%s [flags] packages\n", name) + fmt.Fprintf(os.Stderr, "\t%s [flags] directory\n", name) + fmt.Fprintf(os.Stderr, "\t%s [flags] files... # must be a single package\n", name) + fmt.Fprintf(os.Stderr, "Flags:\n") + flags.PrintDefaults() + } +} + +func parseIgnore(s string) ([]lint.Ignore, error) { + var out []lint.Ignore + if len(s) == 0 { + return nil, nil + } + for _, part := range strings.Fields(s) { + p := strings.Split(part, ":") + if len(p) != 2 { + return nil, errors.New("malformed ignore string") + } + path := p[0] + checks := strings.Split(p[1], ",") + out = append(out, &lint.GlobIgnore{Pattern: path, Checks: checks}) + } + return out, nil +} + +type versionFlag int + +func (v *versionFlag) String() string { + return fmt.Sprintf("1.%d", *v) +} + +func (v *versionFlag) Set(s string) error { + if len(s) < 3 { + return errors.New("invalid Go version") + } + if s[0] != '1' { + return errors.New("invalid Go version") + } + if s[1] != '.' { + return errors.New("invalid Go version") + } + i, err := strconv.Atoi(s[2:]) + *v = versionFlag(i) + return err +} + +func (v *versionFlag) Get() interface{} { + return int(*v) +} + +type list []string + +func (list *list) String() string { + return `"` + strings.Join(*list, ",") + `"` +} + +func (list *list) Set(s string) error { + if s == "" { + *list = nil + return nil + } + + *list = strings.Split(s, ",") + return nil +} + +func FlagSet(name string) *flag.FlagSet { + flags := flag.NewFlagSet("", flag.ExitOnError) + flags.Usage = usage(name, flags) + flags.String("tags", "", "List of `build tags`") + flags.String("ignore", "", "Deprecated: use linter directives instead") + flags.Bool("tests", true, "Include tests") + flags.Bool("version", false, "Print version and exit") + flags.Bool("show-ignored", false, "Don't filter ignored problems") + flags.String("f", "text", "Output `format` (valid choices are 'stylish', 'text' and 'json')") + + flags.Int("debug.max-concurrent-jobs", 0, "Number of jobs to run concurrently") + flags.Bool("debug.print-stats", false, "Print debug statistics") + flags.String("debug.cpuprofile", "", "Write CPU profile to `file`") + flags.String("debug.memprofile", "", "Write memory profile to `file`") + + checks := list{"inherit"} + fail := list{"all"} + flags.Var(&checks, "checks", "Comma-separated list of `checks` to enable.") + flags.Var(&fail, "fail", "Comma-separated list of `checks` that can cause a non-zero exit status.") + + tags := build.Default.ReleaseTags + v := tags[len(tags)-1][2:] + version := new(versionFlag) + if err := version.Set(v); err != nil { + panic(fmt.Sprintf("internal error: %s", err)) + } + + flags.Var(version, "go", "Target Go `version` in the format '1.x'") + return flags +} + +func ProcessFlagSet(cs []lint.Checker, fs *flag.FlagSet) { + tags := fs.Lookup("tags").Value.(flag.Getter).Get().(string) + ignore := fs.Lookup("ignore").Value.(flag.Getter).Get().(string) + tests := fs.Lookup("tests").Value.(flag.Getter).Get().(bool) + goVersion := fs.Lookup("go").Value.(flag.Getter).Get().(int) + formatter := fs.Lookup("f").Value.(flag.Getter).Get().(string) + printVersion := fs.Lookup("version").Value.(flag.Getter).Get().(bool) + showIgnored := fs.Lookup("show-ignored").Value.(flag.Getter).Get().(bool) + + maxConcurrentJobs := fs.Lookup("debug.max-concurrent-jobs").Value.(flag.Getter).Get().(int) + printStats := fs.Lookup("debug.print-stats").Value.(flag.Getter).Get().(bool) + cpuProfile := fs.Lookup("debug.cpuprofile").Value.(flag.Getter).Get().(string) + memProfile := fs.Lookup("debug.memprofile").Value.(flag.Getter).Get().(string) + + cfg := config.Config{} + cfg.Checks = *fs.Lookup("checks").Value.(*list) + + exit := func(code int) { + if cpuProfile != "" { + pprof.StopCPUProfile() + } + if memProfile != "" { + f, err := os.Create(memProfile) + if err != nil { + panic(err) + } + runtime.GC() + pprof.WriteHeapProfile(f) + } + os.Exit(code) + } + if cpuProfile != "" { + f, err := os.Create(cpuProfile) + if err != nil { + log.Fatal(err) + } + pprof.StartCPUProfile(f) + } + + if printVersion { + version.Print() + exit(0) + } + + ps, err := Lint(cs, fs.Args(), &Options{ + Tags: strings.Fields(tags), + LintTests: tests, + Ignores: ignore, + GoVersion: goVersion, + ReturnIgnored: showIgnored, + Config: cfg, + + MaxConcurrentJobs: maxConcurrentJobs, + PrintStats: printStats, + }) + if err != nil { + fmt.Fprintln(os.Stderr, err) + exit(1) + } + + var f format.Formatter + switch formatter { + case "text": + f = format.Text{W: os.Stdout} + case "stylish": + f = &format.Stylish{W: os.Stdout} + case "json": + f = format.JSON{W: os.Stdout} + default: + fmt.Fprintf(os.Stderr, "unsupported output format %q\n", formatter) + exit(2) + } + + var ( + total int + errors int + warnings int + ) + + fail := *fs.Lookup("fail").Value.(*list) + var allChecks []string + for _, p := range ps { + allChecks = append(allChecks, p.Check) + } + + shouldExit := lint.FilterChecks(allChecks, fail) + + total = len(ps) + for _, p := range ps { + if shouldExit[p.Check] { + errors++ + } else { + p.Severity = lint.Warning + warnings++ + } + f.Format(p) + } + if f, ok := f.(format.Statter); ok { + f.Stats(total, errors, warnings) + } + if errors > 0 { + exit(1) + } +} + +type Options struct { + Config config.Config + + Tags []string + LintTests bool + Ignores string + GoVersion int + ReturnIgnored bool + + MaxConcurrentJobs int + PrintStats bool +} + +func Lint(cs []lint.Checker, paths []string, opt *Options) ([]lint.Problem, error) { + stats := lint.PerfStats{ + CheckerInits: map[string]time.Duration{}, + } + + if opt == nil { + opt = &Options{} + } + ignores, err := parseIgnore(opt.Ignores) + if err != nil { + return nil, err + } + + ctx := build.Default + // XXX nothing cares about built tags right now + ctx.BuildTags = opt.Tags + conf := &packages.Config{ + Mode: packages.LoadAllSyntax, + Tests: opt.LintTests, + } + + t := time.Now() + if len(paths) == 0 { + paths = []string{"."} + } + pkgs, err := packages.Load(conf, paths...) + if err != nil { + return nil, err + } + stats.PackageLoading = time.Since(t) + + var problems []lint.Problem + workingPkgs := make([]*packages.Package, 0, len(pkgs)) + for _, pkg := range pkgs { + if pkg.IllTyped { + problems = append(problems, compileErrors(pkg)...) + } else { + workingPkgs = append(workingPkgs, pkg) + } + } + + if len(workingPkgs) == 0 { + return problems, nil + } + + l := &lint.Linter{ + Checkers: cs, + Ignores: ignores, + GoVersion: opt.GoVersion, + ReturnIgnored: opt.ReturnIgnored, + Config: opt.Config, + + MaxConcurrentJobs: opt.MaxConcurrentJobs, + PrintStats: opt.PrintStats, + } + problems = append(problems, l.Lint(workingPkgs, &stats)...) + + return problems, nil +} + +var posRe = regexp.MustCompile(`^(.+?):(\d+):(\d+)?$`) + +func parsePos(pos string) token.Position { + if pos == "-" || pos == "" { + return token.Position{} + } + parts := posRe.FindStringSubmatch(pos) + if parts == nil { + panic(fmt.Sprintf("internal error: malformed position %q", pos)) + } + file := parts[0] + line, _ := strconv.Atoi(parts[1]) + col, _ := strconv.Atoi(parts[2]) + return token.Position{ + Filename: file, + Line: line, + Column: col, + } +} + +func compileErrors(pkg *packages.Package) []lint.Problem { + if !pkg.IllTyped { + return nil + } + if len(pkg.Errors) == 0 { + // transitively ill-typed + var ps []lint.Problem + for _, imp := range pkg.Imports { + ps = append(ps, compileErrors(imp)...) + } + return ps + } + var ps []lint.Problem + for _, err := range pkg.Errors { + p := lint.Problem{ + Position: parsePos(err.Pos), + Text: err.Msg, + Checker: "compiler", + Check: "compile", + } + ps = append(ps, p) + } + return ps +} + +func ProcessArgs(name string, cs []lint.Checker, args []string) { + flags := FlagSet(name) + flags.Parse(args) + + ProcessFlagSet(cs, flags) +} diff --git a/vendor/honnef.co/go/tools/simple/CONTRIBUTING.md b/vendor/honnef.co/go/tools/simple/CONTRIBUTING.md new file mode 100644 index 0000000000..c54c6c50ac --- /dev/null +++ b/vendor/honnef.co/go/tools/simple/CONTRIBUTING.md @@ -0,0 +1,15 @@ +# Contributing to gosimple + +## Before filing an issue: + +### Are you having trouble building gosimple? + +Check you have the latest version of its dependencies. Run +``` +go get -u honnef.co/go/tools/simple +``` +If you still have problems, consider searching for existing issues before filing a new issue. + +## Before sending a pull request: + +Have you understood the purpose of gosimple? Make sure to carefully read `README`. diff --git a/vendor/honnef.co/go/tools/simple/lint.go b/vendor/honnef.co/go/tools/simple/lint.go new file mode 100644 index 0000000000..25de813b8f --- /dev/null +++ b/vendor/honnef.co/go/tools/simple/lint.go @@ -0,0 +1,1734 @@ +// Package simple contains a linter for Go source code. +package simple // import "honnef.co/go/tools/simple" + +import ( + "go/ast" + "go/constant" + "go/token" + "go/types" + "reflect" + "strings" + + . "honnef.co/go/tools/arg" + "honnef.co/go/tools/internal/sharedcheck" + "honnef.co/go/tools/lint" + . "honnef.co/go/tools/lint/lintdsl" + + "golang.org/x/tools/go/types/typeutil" +) + +type Checker struct { + CheckGenerated bool + MS *typeutil.MethodSetCache +} + +func NewChecker() *Checker { + return &Checker{ + MS: &typeutil.MethodSetCache{}, + } +} + +func (*Checker) Name() string { return "gosimple" } +func (*Checker) Prefix() string { return "S" } + +func (c *Checker) Init(prog *lint.Program) {} + +func (c *Checker) Checks() []lint.Check { + return []lint.Check{ + {ID: "S1000", FilterGenerated: true, Fn: c.LintSingleCaseSelect}, + {ID: "S1001", FilterGenerated: true, Fn: c.LintLoopCopy}, + {ID: "S1002", FilterGenerated: true, Fn: c.LintIfBoolCmp}, + {ID: "S1003", FilterGenerated: true, Fn: c.LintStringsContains}, + {ID: "S1004", FilterGenerated: true, Fn: c.LintBytesCompare}, + {ID: "S1005", FilterGenerated: true, Fn: c.LintUnnecessaryBlank}, + {ID: "S1006", FilterGenerated: true, Fn: c.LintForTrue}, + {ID: "S1007", FilterGenerated: true, Fn: c.LintRegexpRaw}, + {ID: "S1008", FilterGenerated: true, Fn: c.LintIfReturn}, + {ID: "S1009", FilterGenerated: true, Fn: c.LintRedundantNilCheckWithLen}, + {ID: "S1010", FilterGenerated: true, Fn: c.LintSlicing}, + {ID: "S1011", FilterGenerated: true, Fn: c.LintLoopAppend}, + {ID: "S1012", FilterGenerated: true, Fn: c.LintTimeSince}, + {ID: "S1016", FilterGenerated: true, Fn: c.LintSimplerStructConversion}, + {ID: "S1017", FilterGenerated: true, Fn: c.LintTrim}, + {ID: "S1018", FilterGenerated: true, Fn: c.LintLoopSlide}, + {ID: "S1019", FilterGenerated: true, Fn: c.LintMakeLenCap}, + {ID: "S1020", FilterGenerated: true, Fn: c.LintAssertNotNil}, + {ID: "S1021", FilterGenerated: true, Fn: c.LintDeclareAssign}, + {ID: "S1023", FilterGenerated: true, Fn: c.LintRedundantBreak}, + {ID: "S1024", FilterGenerated: true, Fn: c.LintTimeUntil}, + {ID: "S1025", FilterGenerated: true, Fn: c.LintRedundantSprintf}, + {ID: "S1028", FilterGenerated: true, Fn: c.LintErrorsNewSprintf}, + {ID: "S1029", FilterGenerated: false, Fn: c.LintRangeStringRunes}, + {ID: "S1030", FilterGenerated: true, Fn: c.LintBytesBufferConversions}, + {ID: "S1031", FilterGenerated: true, Fn: c.LintNilCheckAroundRange}, + {ID: "S1032", FilterGenerated: true, Fn: c.LintSortHelpers}, + } +} + +func (c *Checker) LintSingleCaseSelect(j *lint.Job) { + isSingleSelect := func(node ast.Node) bool { + v, ok := node.(*ast.SelectStmt) + if !ok { + return false + } + return len(v.Body.List) == 1 + } + + seen := map[ast.Node]struct{}{} + fn := func(node ast.Node) bool { + switch v := node.(type) { + case *ast.ForStmt: + if len(v.Body.List) != 1 { + return true + } + if !isSingleSelect(v.Body.List[0]) { + return true + } + if _, ok := v.Body.List[0].(*ast.SelectStmt).Body.List[0].(*ast.CommClause).Comm.(*ast.SendStmt); ok { + // Don't suggest using range for channel sends + return true + } + seen[v.Body.List[0]] = struct{}{} + j.Errorf(node, "should use for range instead of for { select {} }") + case *ast.SelectStmt: + if _, ok := seen[v]; ok { + return true + } + if !isSingleSelect(v) { + return true + } + j.Errorf(node, "should use a simple channel send/receive instead of select with a single case") + return true + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintLoopCopy(j *lint.Job) { + fn := func(node ast.Node) bool { + loop, ok := node.(*ast.RangeStmt) + if !ok { + return true + } + + if loop.Key == nil { + return true + } + if len(loop.Body.List) != 1 { + return true + } + stmt, ok := loop.Body.List[0].(*ast.AssignStmt) + if !ok { + return true + } + if stmt.Tok != token.ASSIGN || len(stmt.Lhs) != 1 || len(stmt.Rhs) != 1 { + return true + } + lhs, ok := stmt.Lhs[0].(*ast.IndexExpr) + if !ok { + return true + } + + if _, ok := TypeOf(j, lhs.X).(*types.Slice); !ok { + return true + } + lidx, ok := lhs.Index.(*ast.Ident) + if !ok { + return true + } + key, ok := loop.Key.(*ast.Ident) + if !ok { + return true + } + if TypeOf(j, lhs) == nil || TypeOf(j, stmt.Rhs[0]) == nil { + return true + } + if ObjectOf(j, lidx) != ObjectOf(j, key) { + return true + } + if !types.Identical(TypeOf(j, lhs), TypeOf(j, stmt.Rhs[0])) { + return true + } + if _, ok := TypeOf(j, loop.X).(*types.Slice); !ok { + return true + } + + if rhs, ok := stmt.Rhs[0].(*ast.IndexExpr); ok { + rx, ok := rhs.X.(*ast.Ident) + _ = rx + if !ok { + return true + } + ridx, ok := rhs.Index.(*ast.Ident) + if !ok { + return true + } + if ObjectOf(j, ridx) != ObjectOf(j, key) { + return true + } + } else if rhs, ok := stmt.Rhs[0].(*ast.Ident); ok { + value, ok := loop.Value.(*ast.Ident) + if !ok { + return true + } + if ObjectOf(j, rhs) != ObjectOf(j, value) { + return true + } + } else { + return true + } + j.Errorf(loop, "should use copy() instead of a loop") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintIfBoolCmp(j *lint.Job) { + fn := func(node ast.Node) bool { + expr, ok := node.(*ast.BinaryExpr) + if !ok || (expr.Op != token.EQL && expr.Op != token.NEQ) { + return true + } + x := IsBoolConst(j, expr.X) + y := IsBoolConst(j, expr.Y) + if !x && !y { + return true + } + var other ast.Expr + var val bool + if x { + val = BoolConst(j, expr.X) + other = expr.Y + } else { + val = BoolConst(j, expr.Y) + other = expr.X + } + basic, ok := TypeOf(j, other).Underlying().(*types.Basic) + if !ok || basic.Kind() != types.Bool { + return true + } + op := "" + if (expr.Op == token.EQL && !val) || (expr.Op == token.NEQ && val) { + op = "!" + } + r := op + Render(j, other) + l1 := len(r) + r = strings.TrimLeft(r, "!") + if (l1-len(r))%2 == 1 { + r = "!" + r + } + if IsInTest(j, node) { + return true + } + j.Errorf(expr, "should omit comparison to bool constant, can be simplified to %s", r) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintBytesBufferConversions(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok || len(call.Args) != 1 { + return true + } + + argCall, ok := call.Args[0].(*ast.CallExpr) + if !ok { + return true + } + sel, ok := argCall.Fun.(*ast.SelectorExpr) + if !ok { + return true + } + + typ := TypeOf(j, call.Fun) + if typ == types.Universe.Lookup("string").Type() && IsCallToAST(j, call.Args[0], "(*bytes.Buffer).Bytes") { + j.Errorf(call, "should use %v.String() instead of %v", Render(j, sel.X), Render(j, call)) + } else if typ, ok := typ.(*types.Slice); ok && typ.Elem() == types.Universe.Lookup("byte").Type() && IsCallToAST(j, call.Args[0], "(*bytes.Buffer).String") { + j.Errorf(call, "should use %v.Bytes() instead of %v", Render(j, sel.X), Render(j, call)) + } + + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintStringsContains(j *lint.Job) { + // map of value to token to bool value + allowed := map[int64]map[token.Token]bool{ + -1: {token.GTR: true, token.NEQ: true, token.EQL: false}, + 0: {token.GEQ: true, token.LSS: false}, + } + fn := func(node ast.Node) bool { + expr, ok := node.(*ast.BinaryExpr) + if !ok { + return true + } + switch expr.Op { + case token.GEQ, token.GTR, token.NEQ, token.LSS, token.EQL: + default: + return true + } + + value, ok := ExprToInt(j, expr.Y) + if !ok { + return true + } + + allowedOps, ok := allowed[value] + if !ok { + return true + } + b, ok := allowedOps[expr.Op] + if !ok { + return true + } + + call, ok := expr.X.(*ast.CallExpr) + if !ok { + return true + } + sel, ok := call.Fun.(*ast.SelectorExpr) + if !ok { + return true + } + pkgIdent, ok := sel.X.(*ast.Ident) + if !ok { + return true + } + funIdent := sel.Sel + if pkgIdent.Name != "strings" && pkgIdent.Name != "bytes" { + return true + } + newFunc := "" + switch funIdent.Name { + case "IndexRune": + newFunc = "ContainsRune" + case "IndexAny": + newFunc = "ContainsAny" + case "Index": + newFunc = "Contains" + default: + return true + } + + prefix := "" + if !b { + prefix = "!" + } + j.Errorf(node, "should use %s%s.%s(%s) instead", prefix, pkgIdent.Name, newFunc, RenderArgs(j, call.Args)) + + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintBytesCompare(j *lint.Job) { + fn := func(node ast.Node) bool { + expr, ok := node.(*ast.BinaryExpr) + if !ok { + return true + } + if expr.Op != token.NEQ && expr.Op != token.EQL { + return true + } + call, ok := expr.X.(*ast.CallExpr) + if !ok { + return true + } + if !IsCallToAST(j, call, "bytes.Compare") { + return true + } + value, ok := ExprToInt(j, expr.Y) + if !ok || value != 0 { + return true + } + args := RenderArgs(j, call.Args) + prefix := "" + if expr.Op == token.NEQ { + prefix = "!" + } + j.Errorf(node, "should use %sbytes.Equal(%s) instead", prefix, args) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintForTrue(j *lint.Job) { + fn := func(node ast.Node) bool { + loop, ok := node.(*ast.ForStmt) + if !ok { + return true + } + if loop.Init != nil || loop.Post != nil { + return true + } + if !IsBoolConst(j, loop.Cond) || !BoolConst(j, loop.Cond) { + return true + } + j.Errorf(loop, "should use for {} instead of for true {}") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintRegexpRaw(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + if !IsCallToAST(j, call, "regexp.MustCompile") && + !IsCallToAST(j, call, "regexp.Compile") { + return true + } + sel, ok := call.Fun.(*ast.SelectorExpr) + if !ok { + return true + } + if len(call.Args) != 1 { + // invalid function call + return true + } + lit, ok := call.Args[Arg("regexp.Compile.expr")].(*ast.BasicLit) + if !ok { + // TODO(dominikh): support string concat, maybe support constants + return true + } + if lit.Kind != token.STRING { + // invalid function call + return true + } + if lit.Value[0] != '"' { + // already a raw string + return true + } + val := lit.Value + if !strings.Contains(val, `\\`) { + return true + } + if strings.Contains(val, "`") { + return true + } + + bs := false + for _, c := range val { + if !bs && c == '\\' { + bs = true + continue + } + if bs && c == '\\' { + bs = false + continue + } + if bs { + // backslash followed by non-backslash -> escape sequence + return true + } + } + + j.Errorf(call, "should use raw string (`...`) with regexp.%s to avoid having to escape twice", sel.Sel.Name) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintIfReturn(j *lint.Job) { + fn := func(node ast.Node) bool { + block, ok := node.(*ast.BlockStmt) + if !ok { + return true + } + l := len(block.List) + if l < 2 { + return true + } + n1, n2 := block.List[l-2], block.List[l-1] + + if len(block.List) >= 3 { + if _, ok := block.List[l-3].(*ast.IfStmt); ok { + // Do not flag a series of if statements + return true + } + } + // if statement with no init, no else, a single condition + // checking an identifier or function call and just a return + // statement in the body, that returns a boolean constant + ifs, ok := n1.(*ast.IfStmt) + if !ok { + return true + } + if ifs.Else != nil || ifs.Init != nil { + return true + } + if len(ifs.Body.List) != 1 { + return true + } + if op, ok := ifs.Cond.(*ast.BinaryExpr); ok { + switch op.Op { + case token.EQL, token.LSS, token.GTR, token.NEQ, token.LEQ, token.GEQ: + default: + return true + } + } + ret1, ok := ifs.Body.List[0].(*ast.ReturnStmt) + if !ok { + return true + } + if len(ret1.Results) != 1 { + return true + } + if !IsBoolConst(j, ret1.Results[0]) { + return true + } + + ret2, ok := n2.(*ast.ReturnStmt) + if !ok { + return true + } + if len(ret2.Results) != 1 { + return true + } + if !IsBoolConst(j, ret2.Results[0]) { + return true + } + j.Errorf(n1, "should use 'return ' instead of 'if { return }; return '") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +// LintRedundantNilCheckWithLen checks for the following reduntant nil-checks: +// +// if x == nil || len(x) == 0 {} +// if x != nil && len(x) != 0 {} +// if x != nil && len(x) == N {} (where N != 0) +// if x != nil && len(x) > N {} +// if x != nil && len(x) >= N {} (where N != 0) +// +func (c *Checker) LintRedundantNilCheckWithLen(j *lint.Job) { + isConstZero := func(expr ast.Expr) (isConst bool, isZero bool) { + _, ok := expr.(*ast.BasicLit) + if ok { + return true, IsZero(expr) + } + id, ok := expr.(*ast.Ident) + if !ok { + return false, false + } + c, ok := ObjectOf(j, id).(*types.Const) + if !ok { + return false, false + } + return true, c.Val().Kind() == constant.Int && c.Val().String() == "0" + } + + fn := func(node ast.Node) bool { + // check that expr is "x || y" or "x && y" + expr, ok := node.(*ast.BinaryExpr) + if !ok { + return true + } + if expr.Op != token.LOR && expr.Op != token.LAND { + return true + } + eqNil := expr.Op == token.LOR + + // check that x is "xx == nil" or "xx != nil" + x, ok := expr.X.(*ast.BinaryExpr) + if !ok { + return true + } + if eqNil && x.Op != token.EQL { + return true + } + if !eqNil && x.Op != token.NEQ { + return true + } + xx, ok := x.X.(*ast.Ident) + if !ok { + return true + } + if !IsNil(j, x.Y) { + return true + } + + // check that y is "len(xx) == 0" or "len(xx) ... " + y, ok := expr.Y.(*ast.BinaryExpr) + if !ok { + return true + } + if eqNil && y.Op != token.EQL { // must be len(xx) *==* 0 + return false + } + yx, ok := y.X.(*ast.CallExpr) + if !ok { + return true + } + yxFun, ok := yx.Fun.(*ast.Ident) + if !ok || yxFun.Name != "len" || len(yx.Args) != 1 { + return true + } + yxArg, ok := yx.Args[Arg("len.v")].(*ast.Ident) + if !ok { + return true + } + if yxArg.Name != xx.Name { + return true + } + + if eqNil && !IsZero(y.Y) { // must be len(x) == *0* + return true + } + + if !eqNil { + isConst, isZero := isConstZero(y.Y) + if !isConst { + return true + } + switch y.Op { + case token.EQL: + // avoid false positive for "xx != nil && len(xx) == 0" + if isZero { + return true + } + case token.GEQ: + // avoid false positive for "xx != nil && len(xx) >= 0" + if isZero { + return true + } + case token.NEQ: + // avoid false positive for "xx != nil && len(xx) != " + if !isZero { + return true + } + case token.GTR: + // ok + default: + return true + } + } + + // finally check that xx type is one of array, slice, map or chan + // this is to prevent false positive in case if xx is a pointer to an array + var nilType string + switch TypeOf(j, xx).(type) { + case *types.Slice: + nilType = "nil slices" + case *types.Map: + nilType = "nil maps" + case *types.Chan: + nilType = "nil channels" + default: + return true + } + j.Errorf(expr, "should omit nil check; len() for %s is defined as zero", nilType) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintSlicing(j *lint.Job) { + fn := func(node ast.Node) bool { + n, ok := node.(*ast.SliceExpr) + if !ok { + return true + } + if n.Max != nil { + return true + } + s, ok := n.X.(*ast.Ident) + if !ok || s.Obj == nil { + return true + } + call, ok := n.High.(*ast.CallExpr) + if !ok || len(call.Args) != 1 || call.Ellipsis.IsValid() { + return true + } + fun, ok := call.Fun.(*ast.Ident) + if !ok || fun.Name != "len" { + return true + } + if _, ok := ObjectOf(j, fun).(*types.Builtin); !ok { + return true + } + arg, ok := call.Args[Arg("len.v")].(*ast.Ident) + if !ok || arg.Obj != s.Obj { + return true + } + j.Errorf(n, "should omit second index in slice, s[a:len(s)] is identical to s[a:]") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func refersTo(j *lint.Job, expr ast.Expr, ident *ast.Ident) bool { + found := false + fn := func(node ast.Node) bool { + ident2, ok := node.(*ast.Ident) + if !ok { + return true + } + if ObjectOf(j, ident) == ObjectOf(j, ident2) { + found = true + return false + } + return true + } + ast.Inspect(expr, fn) + return found +} + +func (c *Checker) LintLoopAppend(j *lint.Job) { + fn := func(node ast.Node) bool { + loop, ok := node.(*ast.RangeStmt) + if !ok { + return true + } + if !IsBlank(loop.Key) { + return true + } + val, ok := loop.Value.(*ast.Ident) + if !ok { + return true + } + if len(loop.Body.List) != 1 { + return true + } + stmt, ok := loop.Body.List[0].(*ast.AssignStmt) + if !ok { + return true + } + if stmt.Tok != token.ASSIGN || len(stmt.Lhs) != 1 || len(stmt.Rhs) != 1 { + return true + } + if refersTo(j, stmt.Lhs[0], val) { + return true + } + call, ok := stmt.Rhs[0].(*ast.CallExpr) + if !ok { + return true + } + if len(call.Args) != 2 || call.Ellipsis.IsValid() { + return true + } + fun, ok := call.Fun.(*ast.Ident) + if !ok { + return true + } + obj := ObjectOf(j, fun) + fn, ok := obj.(*types.Builtin) + if !ok || fn.Name() != "append" { + return true + } + + src := TypeOf(j, loop.X) + dst := TypeOf(j, call.Args[Arg("append.slice")]) + // TODO(dominikh) remove nil check once Go issue #15173 has + // been fixed + if src == nil { + return true + } + if !types.Identical(src, dst) { + return true + } + + if Render(j, stmt.Lhs[0]) != Render(j, call.Args[Arg("append.slice")]) { + return true + } + + el, ok := call.Args[Arg("append.elems")].(*ast.Ident) + if !ok { + return true + } + if ObjectOf(j, val) != ObjectOf(j, el) { + return true + } + j.Errorf(loop, "should replace loop with %s = append(%s, %s...)", + Render(j, stmt.Lhs[0]), Render(j, call.Args[Arg("append.slice")]), Render(j, loop.X)) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintTimeSince(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + sel, ok := call.Fun.(*ast.SelectorExpr) + if !ok { + return true + } + if !IsCallToAST(j, sel.X, "time.Now") { + return true + } + if sel.Sel.Name != "Sub" { + return true + } + j.Errorf(call, "should use time.Since instead of time.Now().Sub") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintTimeUntil(j *lint.Job) { + if !IsGoVersion(j, 8) { + return + } + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + if !IsCallToAST(j, call, "(time.Time).Sub") { + return true + } + if !IsCallToAST(j, call.Args[Arg("(time.Time).Sub.u")], "time.Now") { + return true + } + j.Errorf(call, "should use time.Until instead of t.Sub(time.Now())") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintUnnecessaryBlank(j *lint.Job) { + fn1 := func(node ast.Node) { + assign, ok := node.(*ast.AssignStmt) + if !ok { + return + } + if len(assign.Lhs) != 2 || len(assign.Rhs) != 1 { + return + } + if !IsBlank(assign.Lhs[1]) { + return + } + switch rhs := assign.Rhs[0].(type) { + case *ast.IndexExpr: + // The type-checker should make sure that it's a map, but + // let's be safe. + if _, ok := TypeOf(j, rhs.X).Underlying().(*types.Map); !ok { + return + } + case *ast.UnaryExpr: + if rhs.Op != token.ARROW { + return + } + default: + return + } + cp := *assign + cp.Lhs = cp.Lhs[0:1] + j.Errorf(assign, "should write %s instead of %s", Render(j, &cp), Render(j, assign)) + } + + fn2 := func(node ast.Node) { + stmt, ok := node.(*ast.AssignStmt) + if !ok { + return + } + if len(stmt.Lhs) != len(stmt.Rhs) { + return + } + for i, lh := range stmt.Lhs { + rh := stmt.Rhs[i] + if !IsBlank(lh) { + continue + } + expr, ok := rh.(*ast.UnaryExpr) + if !ok { + continue + } + if expr.Op != token.ARROW { + continue + } + j.Errorf(lh, "'_ = <-ch' can be simplified to '<-ch'") + } + } + + fn3 := func(node ast.Node) { + rs, ok := node.(*ast.RangeStmt) + if !ok { + return + } + + // for x, _ + if !IsBlank(rs.Key) && IsBlank(rs.Value) { + j.Errorf(rs.Value, "should omit value from range; this loop is equivalent to `for %s %s range ...`", Render(j, rs.Key), rs.Tok) + } + // for _, _ || for _ + if IsBlank(rs.Key) && (IsBlank(rs.Value) || rs.Value == nil) { + j.Errorf(rs.Key, "should omit values from range; this loop is equivalent to `for range ...`") + } + } + + fn := func(node ast.Node) bool { + fn1(node) + fn2(node) + if IsGoVersion(j, 4) { + fn3(node) + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintSimplerStructConversion(j *lint.Job) { + var skip ast.Node + fn := func(node ast.Node) bool { + // Do not suggest type conversion between pointers + if unary, ok := node.(*ast.UnaryExpr); ok && unary.Op == token.AND { + if lit, ok := unary.X.(*ast.CompositeLit); ok { + skip = lit + } + return true + } + + if node == skip { + return true + } + + lit, ok := node.(*ast.CompositeLit) + if !ok { + return true + } + typ1, _ := TypeOf(j, lit.Type).(*types.Named) + if typ1 == nil { + return true + } + s1, ok := typ1.Underlying().(*types.Struct) + if !ok { + return true + } + + var typ2 *types.Named + var ident *ast.Ident + getSelType := func(expr ast.Expr) (types.Type, *ast.Ident, bool) { + sel, ok := expr.(*ast.SelectorExpr) + if !ok { + return nil, nil, false + } + ident, ok := sel.X.(*ast.Ident) + if !ok { + return nil, nil, false + } + typ := TypeOf(j, sel.X) + return typ, ident, typ != nil + } + if len(lit.Elts) == 0 { + return true + } + if s1.NumFields() != len(lit.Elts) { + return true + } + for i, elt := range lit.Elts { + var t types.Type + var id *ast.Ident + var ok bool + switch elt := elt.(type) { + case *ast.SelectorExpr: + t, id, ok = getSelType(elt) + if !ok { + return true + } + if i >= s1.NumFields() || s1.Field(i).Name() != elt.Sel.Name { + return true + } + case *ast.KeyValueExpr: + var sel *ast.SelectorExpr + sel, ok = elt.Value.(*ast.SelectorExpr) + if !ok { + return true + } + + if elt.Key.(*ast.Ident).Name != sel.Sel.Name { + return true + } + t, id, ok = getSelType(elt.Value) + } + if !ok { + return true + } + // All fields must be initialized from the same object + if ident != nil && ident.Obj != id.Obj { + return true + } + typ2, _ = t.(*types.Named) + if typ2 == nil { + return true + } + ident = id + } + + if typ2 == nil { + return true + } + + if typ1.Obj().Pkg() != typ2.Obj().Pkg() { + // Do not suggest type conversions between different + // packages. Types in different packages might only match + // by coincidence. Furthermore, if the dependency ever + // adds more fields to its type, it could break the code + // that relies on the type conversion to work. + return true + } + + s2, ok := typ2.Underlying().(*types.Struct) + if !ok { + return true + } + if typ1 == typ2 { + return true + } + if IsGoVersion(j, 8) { + if !types.IdenticalIgnoreTags(s1, s2) { + return true + } + } else { + if !types.Identical(s1, s2) { + return true + } + } + j.Errorf(node, "should convert %s (type %s) to %s instead of using struct literal", + ident.Name, typ2.Obj().Name(), typ1.Obj().Name()) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintTrim(j *lint.Job) { + sameNonDynamic := func(node1, node2 ast.Node) bool { + if reflect.TypeOf(node1) != reflect.TypeOf(node2) { + return false + } + + switch node1 := node1.(type) { + case *ast.Ident: + return node1.Obj == node2.(*ast.Ident).Obj + case *ast.SelectorExpr: + return Render(j, node1) == Render(j, node2) + case *ast.IndexExpr: + return Render(j, node1) == Render(j, node2) + } + return false + } + + isLenOnIdent := func(fn ast.Expr, ident ast.Expr) bool { + call, ok := fn.(*ast.CallExpr) + if !ok { + return false + } + if fn, ok := call.Fun.(*ast.Ident); !ok || fn.Name != "len" { + return false + } + if len(call.Args) != 1 { + return false + } + return sameNonDynamic(call.Args[Arg("len.v")], ident) + } + + fn := func(node ast.Node) bool { + var pkg string + var fun string + + ifstmt, ok := node.(*ast.IfStmt) + if !ok { + return true + } + if ifstmt.Init != nil { + return true + } + if ifstmt.Else != nil { + return true + } + if len(ifstmt.Body.List) != 1 { + return true + } + condCall, ok := ifstmt.Cond.(*ast.CallExpr) + if !ok { + return true + } + call, ok := condCall.Fun.(*ast.SelectorExpr) + if !ok { + return true + } + if IsIdent(call.X, "strings") { + pkg = "strings" + } else if IsIdent(call.X, "bytes") { + pkg = "bytes" + } else { + return true + } + if IsIdent(call.Sel, "HasPrefix") { + fun = "HasPrefix" + } else if IsIdent(call.Sel, "HasSuffix") { + fun = "HasSuffix" + } else { + return true + } + + assign, ok := ifstmt.Body.List[0].(*ast.AssignStmt) + if !ok { + return true + } + if assign.Tok != token.ASSIGN { + return true + } + if len(assign.Lhs) != 1 || len(assign.Rhs) != 1 { + return true + } + if !sameNonDynamic(condCall.Args[0], assign.Lhs[0]) { + return true + } + slice, ok := assign.Rhs[0].(*ast.SliceExpr) + if !ok { + return true + } + if slice.Slice3 { + return true + } + if !sameNonDynamic(slice.X, condCall.Args[0]) { + return true + } + var index ast.Expr + switch fun { + case "HasPrefix": + // TODO(dh) We could detect a High that is len(s), but another + // rule will already flag that, anyway. + if slice.High != nil { + return true + } + index = slice.Low + case "HasSuffix": + if slice.Low != nil { + n, ok := ExprToInt(j, slice.Low) + if !ok || n != 0 { + return true + } + } + index = slice.High + } + + switch index := index.(type) { + case *ast.CallExpr: + if fun != "HasPrefix" { + return true + } + if fn, ok := index.Fun.(*ast.Ident); !ok || fn.Name != "len" { + return true + } + if len(index.Args) != 1 { + return true + } + id3 := index.Args[Arg("len.v")] + switch oid3 := condCall.Args[1].(type) { + case *ast.BasicLit: + if pkg != "strings" { + return false + } + lit, ok := id3.(*ast.BasicLit) + if !ok { + return true + } + s1, ok1 := ExprToString(j, lit) + s2, ok2 := ExprToString(j, condCall.Args[1]) + if !ok1 || !ok2 || s1 != s2 { + return true + } + default: + if !sameNonDynamic(id3, oid3) { + return true + } + } + case *ast.BasicLit, *ast.Ident: + if fun != "HasPrefix" { + return true + } + if pkg != "strings" { + return true + } + string, ok1 := ExprToString(j, condCall.Args[1]) + int, ok2 := ExprToInt(j, slice.Low) + if !ok1 || !ok2 || int != int64(len(string)) { + return true + } + case *ast.BinaryExpr: + if fun != "HasSuffix" { + return true + } + if index.Op != token.SUB { + return true + } + if !isLenOnIdent(index.X, condCall.Args[0]) || + !isLenOnIdent(index.Y, condCall.Args[1]) { + return true + } + default: + return true + } + + var replacement string + switch fun { + case "HasPrefix": + replacement = "TrimPrefix" + case "HasSuffix": + replacement = "TrimSuffix" + } + j.Errorf(ifstmt, "should replace this if statement with an unconditional %s.%s", pkg, replacement) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintLoopSlide(j *lint.Job) { + // TODO(dh): detect bs[i+offset] in addition to bs[offset+i] + // TODO(dh): consider merging this function with LintLoopCopy + // TODO(dh): detect length that is an expression, not a variable name + // TODO(dh): support sliding to a different offset than the beginning of the slice + + fn := func(node ast.Node) bool { + /* + for i := 0; i < n; i++ { + bs[i] = bs[offset+i] + } + + ↓ + + copy(bs[:n], bs[offset:offset+n]) + */ + + loop, ok := node.(*ast.ForStmt) + if !ok || len(loop.Body.List) != 1 || loop.Init == nil || loop.Cond == nil || loop.Post == nil { + return true + } + assign, ok := loop.Init.(*ast.AssignStmt) + if !ok || len(assign.Lhs) != 1 || len(assign.Rhs) != 1 || !IsZero(assign.Rhs[0]) { + return true + } + initvar, ok := assign.Lhs[0].(*ast.Ident) + if !ok { + return true + } + post, ok := loop.Post.(*ast.IncDecStmt) + if !ok || post.Tok != token.INC { + return true + } + postvar, ok := post.X.(*ast.Ident) + if !ok || ObjectOf(j, postvar) != ObjectOf(j, initvar) { + return true + } + bin, ok := loop.Cond.(*ast.BinaryExpr) + if !ok || bin.Op != token.LSS { + return true + } + binx, ok := bin.X.(*ast.Ident) + if !ok || ObjectOf(j, binx) != ObjectOf(j, initvar) { + return true + } + biny, ok := bin.Y.(*ast.Ident) + if !ok { + return true + } + + assign, ok = loop.Body.List[0].(*ast.AssignStmt) + if !ok || len(assign.Lhs) != 1 || len(assign.Rhs) != 1 || assign.Tok != token.ASSIGN { + return true + } + lhs, ok := assign.Lhs[0].(*ast.IndexExpr) + if !ok { + return true + } + rhs, ok := assign.Rhs[0].(*ast.IndexExpr) + if !ok { + return true + } + + bs1, ok := lhs.X.(*ast.Ident) + if !ok { + return true + } + bs2, ok := rhs.X.(*ast.Ident) + if !ok { + return true + } + obj1 := ObjectOf(j, bs1) + obj2 := ObjectOf(j, bs2) + if obj1 != obj2 { + return true + } + if _, ok := obj1.Type().Underlying().(*types.Slice); !ok { + return true + } + + index1, ok := lhs.Index.(*ast.Ident) + if !ok || ObjectOf(j, index1) != ObjectOf(j, initvar) { + return true + } + index2, ok := rhs.Index.(*ast.BinaryExpr) + if !ok || index2.Op != token.ADD { + return true + } + add1, ok := index2.X.(*ast.Ident) + if !ok { + return true + } + add2, ok := index2.Y.(*ast.Ident) + if !ok || ObjectOf(j, add2) != ObjectOf(j, initvar) { + return true + } + + j.Errorf(loop, "should use copy(%s[:%s], %s[%s:]) instead", Render(j, bs1), Render(j, biny), Render(j, bs1), Render(j, add1)) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintMakeLenCap(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + if fn, ok := call.Fun.(*ast.Ident); !ok || fn.Name != "make" { + // FIXME check whether make is indeed the built-in function + return true + } + switch len(call.Args) { + case 2: + // make(T, len) + if _, ok := TypeOf(j, call.Args[Arg("make.t")]).Underlying().(*types.Slice); ok { + break + } + if IsZero(call.Args[Arg("make.size[0]")]) { + j.Errorf(call.Args[Arg("make.size[0]")], "should use make(%s) instead", Render(j, call.Args[Arg("make.t")])) + } + case 3: + // make(T, len, cap) + if Render(j, call.Args[Arg("make.size[0]")]) == Render(j, call.Args[Arg("make.size[1]")]) { + j.Errorf(call.Args[Arg("make.size[0]")], + "should use make(%s, %s) instead", + Render(j, call.Args[Arg("make.t")]), Render(j, call.Args[Arg("make.size[0]")])) + } + } + return false + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintAssertNotNil(j *lint.Job) { + isNilCheck := func(ident *ast.Ident, expr ast.Expr) bool { + xbinop, ok := expr.(*ast.BinaryExpr) + if !ok || xbinop.Op != token.NEQ { + return false + } + xident, ok := xbinop.X.(*ast.Ident) + if !ok || xident.Obj != ident.Obj { + return false + } + if !IsNil(j, xbinop.Y) { + return false + } + return true + } + isOKCheck := func(ident *ast.Ident, expr ast.Expr) bool { + yident, ok := expr.(*ast.Ident) + if !ok || yident.Obj != ident.Obj { + return false + } + return true + } + fn := func(node ast.Node) bool { + ifstmt, ok := node.(*ast.IfStmt) + if !ok { + return true + } + assign, ok := ifstmt.Init.(*ast.AssignStmt) + if !ok || len(assign.Lhs) != 2 || len(assign.Rhs) != 1 || !IsBlank(assign.Lhs[0]) { + return true + } + assert, ok := assign.Rhs[0].(*ast.TypeAssertExpr) + if !ok { + return true + } + binop, ok := ifstmt.Cond.(*ast.BinaryExpr) + if !ok || binop.Op != token.LAND { + return true + } + assertIdent, ok := assert.X.(*ast.Ident) + if !ok { + return true + } + assignIdent, ok := assign.Lhs[1].(*ast.Ident) + if !ok { + return true + } + if !(isNilCheck(assertIdent, binop.X) && isOKCheck(assignIdent, binop.Y)) && + !(isNilCheck(assertIdent, binop.Y) && isOKCheck(assignIdent, binop.X)) { + return true + } + j.Errorf(ifstmt, "when %s is true, %s can't be nil", Render(j, assignIdent), Render(j, assertIdent)) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintDeclareAssign(j *lint.Job) { + fn := func(node ast.Node) bool { + block, ok := node.(*ast.BlockStmt) + if !ok { + return true + } + if len(block.List) < 2 { + return true + } + for i, stmt := range block.List[:len(block.List)-1] { + _ = i + decl, ok := stmt.(*ast.DeclStmt) + if !ok { + continue + } + gdecl, ok := decl.Decl.(*ast.GenDecl) + if !ok || gdecl.Tok != token.VAR || len(gdecl.Specs) != 1 { + continue + } + vspec, ok := gdecl.Specs[0].(*ast.ValueSpec) + if !ok || len(vspec.Names) != 1 || len(vspec.Values) != 0 { + continue + } + + assign, ok := block.List[i+1].(*ast.AssignStmt) + if !ok || assign.Tok != token.ASSIGN { + continue + } + if len(assign.Lhs) != 1 || len(assign.Rhs) != 1 { + continue + } + ident, ok := assign.Lhs[0].(*ast.Ident) + if !ok { + continue + } + if vspec.Names[0].Obj != ident.Obj { + continue + } + + if refersTo(j, assign.Rhs[0], ident) { + continue + } + j.Errorf(decl, "should merge variable declaration with assignment on next line") + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintRedundantBreak(j *lint.Job) { + fn1 := func(node ast.Node) { + clause, ok := node.(*ast.CaseClause) + if !ok { + return + } + if len(clause.Body) < 2 { + return + } + branch, ok := clause.Body[len(clause.Body)-1].(*ast.BranchStmt) + if !ok || branch.Tok != token.BREAK || branch.Label != nil { + return + } + j.Errorf(branch, "redundant break statement") + } + fn2 := func(node ast.Node) { + var ret *ast.FieldList + var body *ast.BlockStmt + switch x := node.(type) { + case *ast.FuncDecl: + ret = x.Type.Results + body = x.Body + case *ast.FuncLit: + ret = x.Type.Results + body = x.Body + default: + return + } + // if the func has results, a return can't be redundant. + // similarly, if there are no statements, there can be + // no return. + if ret != nil || body == nil || len(body.List) < 1 { + return + } + rst, ok := body.List[len(body.List)-1].(*ast.ReturnStmt) + if !ok { + return + } + // we don't need to check rst.Results as we already + // checked x.Type.Results to be nil. + j.Errorf(rst, "redundant return statement") + } + fn := func(node ast.Node) bool { + fn1(node) + fn2(node) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) Implements(j *lint.Job, typ types.Type, iface string) bool { + // OPT(dh): we can cache the type lookup + idx := strings.IndexRune(iface, '.') + var scope *types.Scope + var ifaceName string + if idx == -1 { + scope = types.Universe + ifaceName = iface + } else { + pkgName := iface[:idx] + pkg := j.Program.Package(pkgName) + if pkg == nil { + return false + } + scope = pkg.Types.Scope() + ifaceName = iface[idx+1:] + } + + obj := scope.Lookup(ifaceName) + if obj == nil { + return false + } + i, ok := obj.Type().Underlying().(*types.Interface) + if !ok { + return false + } + return types.Implements(typ, i) +} + +func (c *Checker) LintRedundantSprintf(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + if !IsCallToAST(j, call, "fmt.Sprintf") { + return true + } + if len(call.Args) != 2 { + return true + } + if s, ok := ExprToString(j, call.Args[Arg("fmt.Sprintf.format")]); !ok || s != "%s" { + return true + } + arg := call.Args[Arg("fmt.Sprintf.a[0]")] + typ := TypeOf(j, arg) + + if c.Implements(j, typ, "fmt.Stringer") { + j.Errorf(call, "should use String() instead of fmt.Sprintf") + return true + } + + if typ.Underlying() == types.Universe.Lookup("string").Type() { + if typ == types.Universe.Lookup("string").Type() { + j.Errorf(call, "the argument is already a string, there's no need to use fmt.Sprintf") + } else { + j.Errorf(call, "the argument's underlying type is a string, should use a simple conversion instead of fmt.Sprintf") + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintErrorsNewSprintf(j *lint.Job) { + fn := func(node ast.Node) bool { + if !IsCallToAST(j, node, "errors.New") { + return true + } + call := node.(*ast.CallExpr) + if !IsCallToAST(j, call.Args[Arg("errors.New.text")], "fmt.Sprintf") { + return true + } + j.Errorf(node, "should use fmt.Errorf(...) instead of errors.New(fmt.Sprintf(...))") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) LintRangeStringRunes(j *lint.Job) { + sharedcheck.CheckRangeStringRunes(j) +} + +func (c *Checker) LintNilCheckAroundRange(j *lint.Job) { + fn := func(node ast.Node) bool { + ifstmt, ok := node.(*ast.IfStmt) + if !ok { + return true + } + + cond, ok := ifstmt.Cond.(*ast.BinaryExpr) + if !ok { + return true + } + + if cond.Op != token.NEQ || !IsNil(j, cond.Y) || len(ifstmt.Body.List) != 1 { + return true + } + + loop, ok := ifstmt.Body.List[0].(*ast.RangeStmt) + if !ok { + return true + } + ifXIdent, ok := cond.X.(*ast.Ident) + if !ok { + return true + } + rangeXIdent, ok := loop.X.(*ast.Ident) + if !ok { + return true + } + if ifXIdent.Obj != rangeXIdent.Obj { + return true + } + switch TypeOf(j, rangeXIdent).(type) { + case *types.Slice, *types.Map: + j.Errorf(node, "unnecessary nil check around range") + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func isPermissibleSort(j *lint.Job, node ast.Node) bool { + call := node.(*ast.CallExpr) + typeconv, ok := call.Args[0].(*ast.CallExpr) + if !ok { + return true + } + + sel, ok := typeconv.Fun.(*ast.SelectorExpr) + if !ok { + return true + } + name := SelectorName(j, sel) + switch name { + case "sort.IntSlice", "sort.Float64Slice", "sort.StringSlice": + default: + return true + } + + return false +} + +func (c *Checker) LintSortHelpers(j *lint.Job) { + fnFuncs := func(node ast.Node) bool { + var body *ast.BlockStmt + switch node := node.(type) { + case *ast.FuncLit: + body = node.Body + case *ast.FuncDecl: + body = node.Body + default: + return true + } + if body == nil { + return true + } + + type Error struct { + node lint.Positioner + msg string + } + var errors []Error + permissible := false + fnSorts := func(node ast.Node) bool { + if permissible { + return false + } + if !IsCallToAST(j, node, "sort.Sort") { + return true + } + if isPermissibleSort(j, node) { + permissible = true + return false + } + call := node.(*ast.CallExpr) + typeconv := call.Args[Arg("sort.Sort.data")].(*ast.CallExpr) + sel := typeconv.Fun.(*ast.SelectorExpr) + name := SelectorName(j, sel) + + switch name { + case "sort.IntSlice": + errors = append(errors, Error{node, "should use sort.Ints(...) instead of sort.Sort(sort.IntSlice(...))"}) + case "sort.Float64Slice": + errors = append(errors, Error{node, "should use sort.Float64s(...) instead of sort.Sort(sort.Float64Slice(...))"}) + case "sort.StringSlice": + errors = append(errors, Error{node, "should use sort.Strings(...) instead of sort.Sort(sort.StringSlice(...))"}) + } + return true + } + ast.Inspect(body, fnSorts) + + if permissible { + return false + } + for _, err := range errors { + j.Errorf(err.node, "%s", err.msg) + } + return false + } + + for _, f := range j.Program.Files { + ast.Inspect(f, fnFuncs) + } +} diff --git a/vendor/honnef.co/go/tools/ssa/LICENSE b/vendor/honnef.co/go/tools/ssa/LICENSE new file mode 100644 index 0000000000..aee48041e1 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/LICENSE @@ -0,0 +1,28 @@ +Copyright (c) 2009 The Go Authors. All rights reserved. +Copyright (c) 2016 Dominik Honnef. All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + * Redistributions of source code must retain the above copyright +notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above +copyright notice, this list of conditions and the following disclaimer +in the documentation and/or other materials provided with the +distribution. + * Neither the name of Google Inc. nor the names of its +contributors may be used to endorse or promote products derived from +this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/vendor/honnef.co/go/tools/ssa/blockopt.go b/vendor/honnef.co/go/tools/ssa/blockopt.go new file mode 100644 index 0000000000..22c9a4c0d4 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/blockopt.go @@ -0,0 +1,195 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// Simple block optimizations to simplify the control flow graph. + +// TODO(adonovan): opt: instead of creating several "unreachable" blocks +// per function in the Builder, reuse a single one (e.g. at Blocks[1]) +// to reduce garbage. + +import ( + "fmt" + "os" +) + +// If true, perform sanity checking and show progress at each +// successive iteration of optimizeBlocks. Very verbose. +const debugBlockOpt = false + +// markReachable sets Index=-1 for all blocks reachable from b. +func markReachable(b *BasicBlock) { + b.Index = -1 + for _, succ := range b.Succs { + if succ.Index == 0 { + markReachable(succ) + } + } +} + +func DeleteUnreachableBlocks(f *Function) { + deleteUnreachableBlocks(f) +} + +// deleteUnreachableBlocks marks all reachable blocks of f and +// eliminates (nils) all others, including possibly cyclic subgraphs. +// +func deleteUnreachableBlocks(f *Function) { + const white, black = 0, -1 + // We borrow b.Index temporarily as the mark bit. + for _, b := range f.Blocks { + b.Index = white + } + markReachable(f.Blocks[0]) + if f.Recover != nil { + markReachable(f.Recover) + } + for i, b := range f.Blocks { + if b.Index == white { + for _, c := range b.Succs { + if c.Index == black { + c.removePred(b) // delete white->black edge + } + } + if debugBlockOpt { + fmt.Fprintln(os.Stderr, "unreachable", b) + } + f.Blocks[i] = nil // delete b + } + } + f.removeNilBlocks() +} + +// jumpThreading attempts to apply simple jump-threading to block b, +// in which a->b->c become a->c if b is just a Jump. +// The result is true if the optimization was applied. +// +func jumpThreading(f *Function, b *BasicBlock) bool { + if b.Index == 0 { + return false // don't apply to entry block + } + if b.Instrs == nil { + return false + } + if _, ok := b.Instrs[0].(*Jump); !ok { + return false // not just a jump + } + c := b.Succs[0] + if c == b { + return false // don't apply to degenerate jump-to-self. + } + if c.hasPhi() { + return false // not sound without more effort + } + for j, a := range b.Preds { + a.replaceSucc(b, c) + + // If a now has two edges to c, replace its degenerate If by Jump. + if len(a.Succs) == 2 && a.Succs[0] == c && a.Succs[1] == c { + jump := new(Jump) + jump.setBlock(a) + a.Instrs[len(a.Instrs)-1] = jump + a.Succs = a.Succs[:1] + c.removePred(b) + } else { + if j == 0 { + c.replacePred(b, a) + } else { + c.Preds = append(c.Preds, a) + } + } + + if debugBlockOpt { + fmt.Fprintln(os.Stderr, "jumpThreading", a, b, c) + } + } + f.Blocks[b.Index] = nil // delete b + return true +} + +// fuseBlocks attempts to apply the block fusion optimization to block +// a, in which a->b becomes ab if len(a.Succs)==len(b.Preds)==1. +// The result is true if the optimization was applied. +// +func fuseBlocks(f *Function, a *BasicBlock) bool { + if len(a.Succs) != 1 { + return false + } + b := a.Succs[0] + if len(b.Preds) != 1 { + return false + } + + // Degenerate &&/|| ops may result in a straight-line CFG + // containing φ-nodes. (Ideally we'd replace such them with + // their sole operand but that requires Referrers, built later.) + if b.hasPhi() { + return false // not sound without further effort + } + + // Eliminate jump at end of A, then copy all of B across. + a.Instrs = append(a.Instrs[:len(a.Instrs)-1], b.Instrs...) + for _, instr := range b.Instrs { + instr.setBlock(a) + } + + // A inherits B's successors + a.Succs = append(a.succs2[:0], b.Succs...) + + // Fix up Preds links of all successors of B. + for _, c := range b.Succs { + c.replacePred(b, a) + } + + if debugBlockOpt { + fmt.Fprintln(os.Stderr, "fuseBlocks", a, b) + } + + f.Blocks[b.Index] = nil // delete b + return true +} + +func OptimizeBlocks(f *Function) { + optimizeBlocks(f) +} + +// optimizeBlocks() performs some simple block optimizations on a +// completed function: dead block elimination, block fusion, jump +// threading. +// +func optimizeBlocks(f *Function) { + deleteUnreachableBlocks(f) + + // Loop until no further progress. + changed := true + for changed { + changed = false + + if debugBlockOpt { + f.WriteTo(os.Stderr) + mustSanityCheck(f, nil) + } + + for _, b := range f.Blocks { + // f.Blocks will temporarily contain nils to indicate + // deleted blocks; we remove them at the end. + if b == nil { + continue + } + + // Fuse blocks. b->c becomes bc. + if fuseBlocks(f, b) { + changed = true + } + + // a->b->c becomes a->c if b contains only a Jump. + if jumpThreading(f, b) { + changed = true + continue // (b was disconnected) + } + } + } + f.removeNilBlocks() +} diff --git a/vendor/honnef.co/go/tools/ssa/builder.go b/vendor/honnef.co/go/tools/ssa/builder.go new file mode 100644 index 0000000000..602b27188e --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/builder.go @@ -0,0 +1,2379 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file implements the BUILD phase of SSA construction. +// +// SSA construction has two phases, CREATE and BUILD. In the CREATE phase +// (create.go), all packages are constructed and type-checked and +// definitions of all package members are created, method-sets are +// computed, and wrapper methods are synthesized. +// ssa.Packages are created in arbitrary order. +// +// In the BUILD phase (builder.go), the builder traverses the AST of +// each Go source function and generates SSA instructions for the +// function body. Initializer expressions for package-level variables +// are emitted to the package's init() function in the order specified +// by go/types.Info.InitOrder, then code for each function in the +// package is generated in lexical order. +// The BUILD phases for distinct packages are independent and are +// executed in parallel. +// +// TODO(adonovan): indeed, building functions is now embarrassingly parallel. +// Audit for concurrency then benchmark using more goroutines. +// +// The builder's and Program's indices (maps) are populated and +// mutated during the CREATE phase, but during the BUILD phase they +// remain constant. The sole exception is Prog.methodSets and its +// related maps, which are protected by a dedicated mutex. + +import ( + "fmt" + "go/ast" + exact "go/constant" + "go/token" + "go/types" + "os" + "sync" +) + +type opaqueType struct { + types.Type + name string +} + +func (t *opaqueType) String() string { return t.name } + +var ( + varOk = newVar("ok", tBool) + varIndex = newVar("index", tInt) + + // Type constants. + tBool = types.Typ[types.Bool] + tByte = types.Typ[types.Byte] + tInt = types.Typ[types.Int] + tInvalid = types.Typ[types.Invalid] + tString = types.Typ[types.String] + tUntypedNil = types.Typ[types.UntypedNil] + tRangeIter = &opaqueType{nil, "iter"} // the type of all "range" iterators + tEface = types.NewInterface(nil, nil).Complete() + + // SSA Value constants. + vZero = intConst(0) + vOne = intConst(1) + vTrue = NewConst(exact.MakeBool(true), tBool) +) + +// builder holds state associated with the package currently being built. +// Its methods contain all the logic for AST-to-SSA conversion. +type builder struct{} + +// cond emits to fn code to evaluate boolean condition e and jump +// to t or f depending on its value, performing various simplifications. +// +// Postcondition: fn.currentBlock is nil. +// +func (b *builder) cond(fn *Function, e ast.Expr, t, f *BasicBlock) { + switch e := e.(type) { + case *ast.ParenExpr: + b.cond(fn, e.X, t, f) + return + + case *ast.BinaryExpr: + switch e.Op { + case token.LAND: + ltrue := fn.newBasicBlock("cond.true") + b.cond(fn, e.X, ltrue, f) + fn.currentBlock = ltrue + b.cond(fn, e.Y, t, f) + return + + case token.LOR: + lfalse := fn.newBasicBlock("cond.false") + b.cond(fn, e.X, t, lfalse) + fn.currentBlock = lfalse + b.cond(fn, e.Y, t, f) + return + } + + case *ast.UnaryExpr: + if e.Op == token.NOT { + b.cond(fn, e.X, f, t) + return + } + } + + // A traditional compiler would simplify "if false" (etc) here + // but we do not, for better fidelity to the source code. + // + // The value of a constant condition may be platform-specific, + // and may cause blocks that are reachable in some configuration + // to be hidden from subsequent analyses such as bug-finding tools. + emitIf(fn, b.expr(fn, e), t, f) +} + +// logicalBinop emits code to fn to evaluate e, a &&- or +// ||-expression whose reified boolean value is wanted. +// The value is returned. +// +func (b *builder) logicalBinop(fn *Function, e *ast.BinaryExpr) Value { + rhs := fn.newBasicBlock("binop.rhs") + done := fn.newBasicBlock("binop.done") + + // T(e) = T(e.X) = T(e.Y) after untyped constants have been + // eliminated. + // TODO(adonovan): not true; MyBool==MyBool yields UntypedBool. + t := fn.Pkg.typeOf(e) + + var short Value // value of the short-circuit path + switch e.Op { + case token.LAND: + b.cond(fn, e.X, rhs, done) + short = NewConst(exact.MakeBool(false), t) + + case token.LOR: + b.cond(fn, e.X, done, rhs) + short = NewConst(exact.MakeBool(true), t) + } + + // Is rhs unreachable? + if rhs.Preds == nil { + // Simplify false&&y to false, true||y to true. + fn.currentBlock = done + return short + } + + // Is done unreachable? + if done.Preds == nil { + // Simplify true&&y (or false||y) to y. + fn.currentBlock = rhs + return b.expr(fn, e.Y) + } + + // All edges from e.X to done carry the short-circuit value. + var edges []Value + for range done.Preds { + edges = append(edges, short) + } + + // The edge from e.Y to done carries the value of e.Y. + fn.currentBlock = rhs + edges = append(edges, b.expr(fn, e.Y)) + emitJump(fn, done) + fn.currentBlock = done + + phi := &Phi{Edges: edges, Comment: e.Op.String()} + phi.pos = e.OpPos + phi.typ = t + return done.emit(phi) +} + +// exprN lowers a multi-result expression e to SSA form, emitting code +// to fn and returning a single Value whose type is a *types.Tuple. +// The caller must access the components via Extract. +// +// Multi-result expressions include CallExprs in a multi-value +// assignment or return statement, and "value,ok" uses of +// TypeAssertExpr, IndexExpr (when X is a map), and UnaryExpr (when Op +// is token.ARROW). +// +func (b *builder) exprN(fn *Function, e ast.Expr) Value { + typ := fn.Pkg.typeOf(e).(*types.Tuple) + switch e := e.(type) { + case *ast.ParenExpr: + return b.exprN(fn, e.X) + + case *ast.CallExpr: + // Currently, no built-in function nor type conversion + // has multiple results, so we can avoid some of the + // cases for single-valued CallExpr. + var c Call + b.setCall(fn, e, &c.Call) + c.typ = typ + return fn.emit(&c) + + case *ast.IndexExpr: + mapt := fn.Pkg.typeOf(e.X).Underlying().(*types.Map) + lookup := &Lookup{ + X: b.expr(fn, e.X), + Index: emitConv(fn, b.expr(fn, e.Index), mapt.Key()), + CommaOk: true, + } + lookup.setType(typ) + lookup.setPos(e.Lbrack) + return fn.emit(lookup) + + case *ast.TypeAssertExpr: + return emitTypeTest(fn, b.expr(fn, e.X), typ.At(0).Type(), e.Lparen) + + case *ast.UnaryExpr: // must be receive <- + unop := &UnOp{ + Op: token.ARROW, + X: b.expr(fn, e.X), + CommaOk: true, + } + unop.setType(typ) + unop.setPos(e.OpPos) + return fn.emit(unop) + } + panic(fmt.Sprintf("exprN(%T) in %s", e, fn)) +} + +// builtin emits to fn SSA instructions to implement a call to the +// built-in function obj with the specified arguments +// and return type. It returns the value defined by the result. +// +// The result is nil if no special handling was required; in this case +// the caller should treat this like an ordinary library function +// call. +// +func (b *builder) builtin(fn *Function, obj *types.Builtin, args []ast.Expr, typ types.Type, pos token.Pos) Value { + switch obj.Name() { + case "make": + switch typ.Underlying().(type) { + case *types.Slice: + n := b.expr(fn, args[1]) + m := n + if len(args) == 3 { + m = b.expr(fn, args[2]) + } + if m, ok := m.(*Const); ok { + // treat make([]T, n, m) as new([m]T)[:n] + cap := m.Int64() + at := types.NewArray(typ.Underlying().(*types.Slice).Elem(), cap) + alloc := emitNew(fn, at, pos) + alloc.Comment = "makeslice" + v := &Slice{ + X: alloc, + High: n, + } + v.setPos(pos) + v.setType(typ) + return fn.emit(v) + } + v := &MakeSlice{ + Len: n, + Cap: m, + } + v.setPos(pos) + v.setType(typ) + return fn.emit(v) + + case *types.Map: + var res Value + if len(args) == 2 { + res = b.expr(fn, args[1]) + } + v := &MakeMap{Reserve: res} + v.setPos(pos) + v.setType(typ) + return fn.emit(v) + + case *types.Chan: + var sz Value = vZero + if len(args) == 2 { + sz = b.expr(fn, args[1]) + } + v := &MakeChan{Size: sz} + v.setPos(pos) + v.setType(typ) + return fn.emit(v) + } + + case "new": + alloc := emitNew(fn, deref(typ), pos) + alloc.Comment = "new" + return alloc + + case "len", "cap": + // Special case: len or cap of an array or *array is + // based on the type, not the value which may be nil. + // We must still evaluate the value, though. (If it + // was side-effect free, the whole call would have + // been constant-folded.) + t := deref(fn.Pkg.typeOf(args[0])).Underlying() + if at, ok := t.(*types.Array); ok { + b.expr(fn, args[0]) // for effects only + return intConst(at.Len()) + } + // Otherwise treat as normal. + + case "panic": + fn.emit(&Panic{ + X: emitConv(fn, b.expr(fn, args[0]), tEface), + pos: pos, + }) + fn.currentBlock = fn.newBasicBlock("unreachable") + return vTrue // any non-nil Value will do + } + return nil // treat all others as a regular function call +} + +// addr lowers a single-result addressable expression e to SSA form, +// emitting code to fn and returning the location (an lvalue) defined +// by the expression. +// +// If escaping is true, addr marks the base variable of the +// addressable expression e as being a potentially escaping pointer +// value. For example, in this code: +// +// a := A{ +// b: [1]B{B{c: 1}} +// } +// return &a.b[0].c +// +// the application of & causes a.b[0].c to have its address taken, +// which means that ultimately the local variable a must be +// heap-allocated. This is a simple but very conservative escape +// analysis. +// +// Operations forming potentially escaping pointers include: +// - &x, including when implicit in method call or composite literals. +// - a[:] iff a is an array (not *array) +// - references to variables in lexically enclosing functions. +// +func (b *builder) addr(fn *Function, e ast.Expr, escaping bool) lvalue { + switch e := e.(type) { + case *ast.Ident: + if isBlankIdent(e) { + return blank{} + } + obj := fn.Pkg.objectOf(e) + v := fn.Prog.packageLevelValue(obj) // var (address) + if v == nil { + v = fn.lookup(obj, escaping) + } + return &address{addr: v, pos: e.Pos(), expr: e} + + case *ast.CompositeLit: + t := deref(fn.Pkg.typeOf(e)) + var v *Alloc + if escaping { + v = emitNew(fn, t, e.Lbrace) + } else { + v = fn.addLocal(t, e.Lbrace) + } + v.Comment = "complit" + var sb storebuf + b.compLit(fn, v, e, true, &sb) + sb.emit(fn) + return &address{addr: v, pos: e.Lbrace, expr: e} + + case *ast.ParenExpr: + return b.addr(fn, e.X, escaping) + + case *ast.SelectorExpr: + sel, ok := fn.Pkg.info.Selections[e] + if !ok { + // qualified identifier + return b.addr(fn, e.Sel, escaping) + } + if sel.Kind() != types.FieldVal { + panic(sel) + } + wantAddr := true + v := b.receiver(fn, e.X, wantAddr, escaping, sel) + last := len(sel.Index()) - 1 + return &address{ + addr: emitFieldSelection(fn, v, sel.Index()[last], true, e.Sel), + pos: e.Sel.Pos(), + expr: e.Sel, + } + + case *ast.IndexExpr: + var x Value + var et types.Type + switch t := fn.Pkg.typeOf(e.X).Underlying().(type) { + case *types.Array: + x = b.addr(fn, e.X, escaping).address(fn) + et = types.NewPointer(t.Elem()) + case *types.Pointer: // *array + x = b.expr(fn, e.X) + et = types.NewPointer(t.Elem().Underlying().(*types.Array).Elem()) + case *types.Slice: + x = b.expr(fn, e.X) + et = types.NewPointer(t.Elem()) + case *types.Map: + return &element{ + m: b.expr(fn, e.X), + k: emitConv(fn, b.expr(fn, e.Index), t.Key()), + t: t.Elem(), + pos: e.Lbrack, + } + default: + panic("unexpected container type in IndexExpr: " + t.String()) + } + v := &IndexAddr{ + X: x, + Index: emitConv(fn, b.expr(fn, e.Index), tInt), + } + v.setPos(e.Lbrack) + v.setType(et) + return &address{addr: fn.emit(v), pos: e.Lbrack, expr: e} + + case *ast.StarExpr: + return &address{addr: b.expr(fn, e.X), pos: e.Star, expr: e} + } + + panic(fmt.Sprintf("unexpected address expression: %T", e)) +} + +type store struct { + lhs lvalue + rhs Value +} + +type storebuf struct{ stores []store } + +func (sb *storebuf) store(lhs lvalue, rhs Value) { + sb.stores = append(sb.stores, store{lhs, rhs}) +} + +func (sb *storebuf) emit(fn *Function) { + for _, s := range sb.stores { + s.lhs.store(fn, s.rhs) + } +} + +// assign emits to fn code to initialize the lvalue loc with the value +// of expression e. If isZero is true, assign assumes that loc holds +// the zero value for its type. +// +// This is equivalent to loc.store(fn, b.expr(fn, e)), but may generate +// better code in some cases, e.g., for composite literals in an +// addressable location. +// +// If sb is not nil, assign generates code to evaluate expression e, but +// not to update loc. Instead, the necessary stores are appended to the +// storebuf sb so that they can be executed later. This allows correct +// in-place update of existing variables when the RHS is a composite +// literal that may reference parts of the LHS. +// +func (b *builder) assign(fn *Function, loc lvalue, e ast.Expr, isZero bool, sb *storebuf) { + // Can we initialize it in place? + if e, ok := unparen(e).(*ast.CompositeLit); ok { + // A CompositeLit never evaluates to a pointer, + // so if the type of the location is a pointer, + // an &-operation is implied. + if _, ok := loc.(blank); !ok { // avoid calling blank.typ() + if isPointer(loc.typ()) { + ptr := b.addr(fn, e, true).address(fn) + // copy address + if sb != nil { + sb.store(loc, ptr) + } else { + loc.store(fn, ptr) + } + return + } + } + + if _, ok := loc.(*address); ok { + if isInterface(loc.typ()) { + // e.g. var x interface{} = T{...} + // Can't in-place initialize an interface value. + // Fall back to copying. + } else { + // x = T{...} or x := T{...} + addr := loc.address(fn) + if sb != nil { + b.compLit(fn, addr, e, isZero, sb) + } else { + var sb storebuf + b.compLit(fn, addr, e, isZero, &sb) + sb.emit(fn) + } + + // Subtle: emit debug ref for aggregate types only; + // slice and map are handled by store ops in compLit. + switch loc.typ().Underlying().(type) { + case *types.Struct, *types.Array: + emitDebugRef(fn, e, addr, true) + } + + return + } + } + } + + // simple case: just copy + rhs := b.expr(fn, e) + if sb != nil { + sb.store(loc, rhs) + } else { + loc.store(fn, rhs) + } +} + +// expr lowers a single-result expression e to SSA form, emitting code +// to fn and returning the Value defined by the expression. +// +func (b *builder) expr(fn *Function, e ast.Expr) Value { + e = unparen(e) + + tv := fn.Pkg.info.Types[e] + + // Is expression a constant? + if tv.Value != nil { + return NewConst(tv.Value, tv.Type) + } + + var v Value + if tv.Addressable() { + // Prefer pointer arithmetic ({Index,Field}Addr) followed + // by Load over subelement extraction (e.g. Index, Field), + // to avoid large copies. + v = b.addr(fn, e, false).load(fn) + } else { + v = b.expr0(fn, e, tv) + } + if fn.debugInfo() { + emitDebugRef(fn, e, v, false) + } + return v +} + +func (b *builder) expr0(fn *Function, e ast.Expr, tv types.TypeAndValue) Value { + switch e := e.(type) { + case *ast.BasicLit: + panic("non-constant BasicLit") // unreachable + + case *ast.FuncLit: + fn2 := &Function{ + name: fmt.Sprintf("%s$%d", fn.Name(), 1+len(fn.AnonFuncs)), + Signature: fn.Pkg.typeOf(e.Type).Underlying().(*types.Signature), + pos: e.Type.Func, + parent: fn, + Pkg: fn.Pkg, + Prog: fn.Prog, + syntax: e, + } + fn.AnonFuncs = append(fn.AnonFuncs, fn2) + b.buildFunction(fn2) + if fn2.FreeVars == nil { + return fn2 + } + v := &MakeClosure{Fn: fn2} + v.setType(tv.Type) + for _, fv := range fn2.FreeVars { + v.Bindings = append(v.Bindings, fv.outer) + fv.outer = nil + } + return fn.emit(v) + + case *ast.TypeAssertExpr: // single-result form only + return emitTypeAssert(fn, b.expr(fn, e.X), tv.Type, e.Lparen) + + case *ast.CallExpr: + if fn.Pkg.info.Types[e.Fun].IsType() { + // Explicit type conversion, e.g. string(x) or big.Int(x) + x := b.expr(fn, e.Args[0]) + y := emitConv(fn, x, tv.Type) + if y != x { + switch y := y.(type) { + case *Convert: + y.pos = e.Lparen + case *ChangeType: + y.pos = e.Lparen + case *MakeInterface: + y.pos = e.Lparen + } + } + return y + } + // Call to "intrinsic" built-ins, e.g. new, make, panic. + if id, ok := unparen(e.Fun).(*ast.Ident); ok { + if obj, ok := fn.Pkg.info.Uses[id].(*types.Builtin); ok { + if v := b.builtin(fn, obj, e.Args, tv.Type, e.Lparen); v != nil { + return v + } + } + } + // Regular function call. + var v Call + b.setCall(fn, e, &v.Call) + v.setType(tv.Type) + return fn.emit(&v) + + case *ast.UnaryExpr: + switch e.Op { + case token.AND: // &X --- potentially escaping. + addr := b.addr(fn, e.X, true) + if _, ok := unparen(e.X).(*ast.StarExpr); ok { + // &*p must panic if p is nil (http://golang.org/s/go12nil). + // For simplicity, we'll just (suboptimally) rely + // on the side effects of a load. + // TODO(adonovan): emit dedicated nilcheck. + addr.load(fn) + } + return addr.address(fn) + case token.ADD: + return b.expr(fn, e.X) + case token.NOT, token.ARROW, token.SUB, token.XOR: // ! <- - ^ + v := &UnOp{ + Op: e.Op, + X: b.expr(fn, e.X), + } + v.setPos(e.OpPos) + v.setType(tv.Type) + return fn.emit(v) + default: + panic(e.Op) + } + + case *ast.BinaryExpr: + switch e.Op { + case token.LAND, token.LOR: + return b.logicalBinop(fn, e) + case token.SHL, token.SHR: + fallthrough + case token.ADD, token.SUB, token.MUL, token.QUO, token.REM, token.AND, token.OR, token.XOR, token.AND_NOT: + return emitArith(fn, e.Op, b.expr(fn, e.X), b.expr(fn, e.Y), tv.Type, e.OpPos) + + case token.EQL, token.NEQ, token.GTR, token.LSS, token.LEQ, token.GEQ: + cmp := emitCompare(fn, e.Op, b.expr(fn, e.X), b.expr(fn, e.Y), e.OpPos) + // The type of x==y may be UntypedBool. + return emitConv(fn, cmp, DefaultType(tv.Type)) + default: + panic("illegal op in BinaryExpr: " + e.Op.String()) + } + + case *ast.SliceExpr: + var low, high, max Value + var x Value + switch fn.Pkg.typeOf(e.X).Underlying().(type) { + case *types.Array: + // Potentially escaping. + x = b.addr(fn, e.X, true).address(fn) + case *types.Basic, *types.Slice, *types.Pointer: // *array + x = b.expr(fn, e.X) + default: + panic("unreachable") + } + if e.High != nil { + high = b.expr(fn, e.High) + } + if e.Low != nil { + low = b.expr(fn, e.Low) + } + if e.Slice3 { + max = b.expr(fn, e.Max) + } + v := &Slice{ + X: x, + Low: low, + High: high, + Max: max, + } + v.setPos(e.Lbrack) + v.setType(tv.Type) + return fn.emit(v) + + case *ast.Ident: + obj := fn.Pkg.info.Uses[e] + // Universal built-in or nil? + switch obj := obj.(type) { + case *types.Builtin: + return &Builtin{name: obj.Name(), sig: tv.Type.(*types.Signature)} + case *types.Nil: + return nilConst(tv.Type) + } + // Package-level func or var? + if v := fn.Prog.packageLevelValue(obj); v != nil { + if _, ok := obj.(*types.Var); ok { + return emitLoad(fn, v) // var (address) + } + return v // (func) + } + // Local var. + return emitLoad(fn, fn.lookup(obj, false)) // var (address) + + case *ast.SelectorExpr: + sel, ok := fn.Pkg.info.Selections[e] + if !ok { + // qualified identifier + return b.expr(fn, e.Sel) + } + switch sel.Kind() { + case types.MethodExpr: + // (*T).f or T.f, the method f from the method-set of type T. + // The result is a "thunk". + return emitConv(fn, makeThunk(fn.Prog, sel), tv.Type) + + case types.MethodVal: + // e.f where e is an expression and f is a method. + // The result is a "bound". + obj := sel.Obj().(*types.Func) + rt := recvType(obj) + wantAddr := isPointer(rt) + escaping := true + v := b.receiver(fn, e.X, wantAddr, escaping, sel) + if isInterface(rt) { + // If v has interface type I, + // we must emit a check that v is non-nil. + // We use: typeassert v.(I). + emitTypeAssert(fn, v, rt, token.NoPos) + } + c := &MakeClosure{ + Fn: makeBound(fn.Prog, obj), + Bindings: []Value{v}, + } + c.setPos(e.Sel.Pos()) + c.setType(tv.Type) + return fn.emit(c) + + case types.FieldVal: + indices := sel.Index() + last := len(indices) - 1 + v := b.expr(fn, e.X) + v = emitImplicitSelections(fn, v, indices[:last]) + v = emitFieldSelection(fn, v, indices[last], false, e.Sel) + return v + } + + panic("unexpected expression-relative selector") + + case *ast.IndexExpr: + switch t := fn.Pkg.typeOf(e.X).Underlying().(type) { + case *types.Array: + // Non-addressable array (in a register). + v := &Index{ + X: b.expr(fn, e.X), + Index: emitConv(fn, b.expr(fn, e.Index), tInt), + } + v.setPos(e.Lbrack) + v.setType(t.Elem()) + return fn.emit(v) + + case *types.Map: + // Maps are not addressable. + mapt := fn.Pkg.typeOf(e.X).Underlying().(*types.Map) + v := &Lookup{ + X: b.expr(fn, e.X), + Index: emitConv(fn, b.expr(fn, e.Index), mapt.Key()), + } + v.setPos(e.Lbrack) + v.setType(mapt.Elem()) + return fn.emit(v) + + case *types.Basic: // => string + // Strings are not addressable. + v := &Lookup{ + X: b.expr(fn, e.X), + Index: b.expr(fn, e.Index), + } + v.setPos(e.Lbrack) + v.setType(tByte) + return fn.emit(v) + + case *types.Slice, *types.Pointer: // *array + // Addressable slice/array; use IndexAddr and Load. + return b.addr(fn, e, false).load(fn) + + default: + panic("unexpected container type in IndexExpr: " + t.String()) + } + + case *ast.CompositeLit, *ast.StarExpr: + // Addressable types (lvalues) + return b.addr(fn, e, false).load(fn) + } + + panic(fmt.Sprintf("unexpected expr: %T", e)) +} + +// stmtList emits to fn code for all statements in list. +func (b *builder) stmtList(fn *Function, list []ast.Stmt) { + for _, s := range list { + b.stmt(fn, s) + } +} + +// receiver emits to fn code for expression e in the "receiver" +// position of selection e.f (where f may be a field or a method) and +// returns the effective receiver after applying the implicit field +// selections of sel. +// +// wantAddr requests that the result is an an address. If +// !sel.Indirect(), this may require that e be built in addr() mode; it +// must thus be addressable. +// +// escaping is defined as per builder.addr(). +// +func (b *builder) receiver(fn *Function, e ast.Expr, wantAddr, escaping bool, sel *types.Selection) Value { + var v Value + if wantAddr && !sel.Indirect() && !isPointer(fn.Pkg.typeOf(e)) { + v = b.addr(fn, e, escaping).address(fn) + } else { + v = b.expr(fn, e) + } + + last := len(sel.Index()) - 1 + v = emitImplicitSelections(fn, v, sel.Index()[:last]) + if !wantAddr && isPointer(v.Type()) { + v = emitLoad(fn, v) + } + return v +} + +// setCallFunc populates the function parts of a CallCommon structure +// (Func, Method, Recv, Args[0]) based on the kind of invocation +// occurring in e. +// +func (b *builder) setCallFunc(fn *Function, e *ast.CallExpr, c *CallCommon) { + c.pos = e.Lparen + + // Is this a method call? + if selector, ok := unparen(e.Fun).(*ast.SelectorExpr); ok { + sel, ok := fn.Pkg.info.Selections[selector] + if ok && sel.Kind() == types.MethodVal { + obj := sel.Obj().(*types.Func) + recv := recvType(obj) + wantAddr := isPointer(recv) + escaping := true + v := b.receiver(fn, selector.X, wantAddr, escaping, sel) + if isInterface(recv) { + // Invoke-mode call. + c.Value = v + c.Method = obj + } else { + // "Call"-mode call. + c.Value = fn.Prog.declaredFunc(obj) + c.Args = append(c.Args, v) + } + return + } + + // sel.Kind()==MethodExpr indicates T.f() or (*T).f(): + // a statically dispatched call to the method f in the + // method-set of T or *T. T may be an interface. + // + // e.Fun would evaluate to a concrete method, interface + // wrapper function, or promotion wrapper. + // + // For now, we evaluate it in the usual way. + // + // TODO(adonovan): opt: inline expr() here, to make the + // call static and to avoid generation of wrappers. + // It's somewhat tricky as it may consume the first + // actual parameter if the call is "invoke" mode. + // + // Examples: + // type T struct{}; func (T) f() {} // "call" mode + // type T interface { f() } // "invoke" mode + // + // type S struct{ T } + // + // var s S + // S.f(s) + // (*S).f(&s) + // + // Suggested approach: + // - consume the first actual parameter expression + // and build it with b.expr(). + // - apply implicit field selections. + // - use MethodVal logic to populate fields of c. + } + + // Evaluate the function operand in the usual way. + c.Value = b.expr(fn, e.Fun) +} + +// emitCallArgs emits to f code for the actual parameters of call e to +// a (possibly built-in) function of effective type sig. +// The argument values are appended to args, which is then returned. +// +func (b *builder) emitCallArgs(fn *Function, sig *types.Signature, e *ast.CallExpr, args []Value) []Value { + // f(x, y, z...): pass slice z straight through. + if e.Ellipsis != 0 { + for i, arg := range e.Args { + v := emitConv(fn, b.expr(fn, arg), sig.Params().At(i).Type()) + args = append(args, v) + } + return args + } + + offset := len(args) // 1 if call has receiver, 0 otherwise + + // Evaluate actual parameter expressions. + // + // If this is a chained call of the form f(g()) where g has + // multiple return values (MRV), they are flattened out into + // args; a suffix of them may end up in a varargs slice. + for _, arg := range e.Args { + v := b.expr(fn, arg) + if ttuple, ok := v.Type().(*types.Tuple); ok { // MRV chain + for i, n := 0, ttuple.Len(); i < n; i++ { + args = append(args, emitExtract(fn, v, i)) + } + } else { + args = append(args, v) + } + } + + // Actual->formal assignability conversions for normal parameters. + np := sig.Params().Len() // number of normal parameters + if sig.Variadic() { + np-- + } + for i := 0; i < np; i++ { + args[offset+i] = emitConv(fn, args[offset+i], sig.Params().At(i).Type()) + } + + // Actual->formal assignability conversions for variadic parameter, + // and construction of slice. + if sig.Variadic() { + varargs := args[offset+np:] + st := sig.Params().At(np).Type().(*types.Slice) + vt := st.Elem() + if len(varargs) == 0 { + args = append(args, nilConst(st)) + } else { + // Replace a suffix of args with a slice containing it. + at := types.NewArray(vt, int64(len(varargs))) + a := emitNew(fn, at, token.NoPos) + a.setPos(e.Rparen) + a.Comment = "varargs" + for i, arg := range varargs { + iaddr := &IndexAddr{ + X: a, + Index: intConst(int64(i)), + } + iaddr.setType(types.NewPointer(vt)) + fn.emit(iaddr) + emitStore(fn, iaddr, arg, arg.Pos()) + } + s := &Slice{X: a} + s.setType(st) + args[offset+np] = fn.emit(s) + args = args[:offset+np+1] + } + } + return args +} + +// setCall emits to fn code to evaluate all the parameters of a function +// call e, and populates *c with those values. +// +func (b *builder) setCall(fn *Function, e *ast.CallExpr, c *CallCommon) { + // First deal with the f(...) part and optional receiver. + b.setCallFunc(fn, e, c) + + // Then append the other actual parameters. + sig, _ := fn.Pkg.typeOf(e.Fun).Underlying().(*types.Signature) + if sig == nil { + panic(fmt.Sprintf("no signature for call of %s", e.Fun)) + } + c.Args = b.emitCallArgs(fn, sig, e, c.Args) +} + +// assignOp emits to fn code to perform loc += incr or loc -= incr. +func (b *builder) assignOp(fn *Function, loc lvalue, incr Value, op token.Token, pos token.Pos) { + oldv := loc.load(fn) + loc.store(fn, emitArith(fn, op, oldv, emitConv(fn, incr, oldv.Type()), loc.typ(), pos)) +} + +// localValueSpec emits to fn code to define all of the vars in the +// function-local ValueSpec, spec. +// +func (b *builder) localValueSpec(fn *Function, spec *ast.ValueSpec) { + switch { + case len(spec.Values) == len(spec.Names): + // e.g. var x, y = 0, 1 + // 1:1 assignment + for i, id := range spec.Names { + if !isBlankIdent(id) { + fn.addLocalForIdent(id) + } + lval := b.addr(fn, id, false) // non-escaping + b.assign(fn, lval, spec.Values[i], true, nil) + } + + case len(spec.Values) == 0: + // e.g. var x, y int + // Locals are implicitly zero-initialized. + for _, id := range spec.Names { + if !isBlankIdent(id) { + lhs := fn.addLocalForIdent(id) + if fn.debugInfo() { + emitDebugRef(fn, id, lhs, true) + } + } + } + + default: + // e.g. var x, y = pos() + tuple := b.exprN(fn, spec.Values[0]) + for i, id := range spec.Names { + if !isBlankIdent(id) { + fn.addLocalForIdent(id) + lhs := b.addr(fn, id, false) // non-escaping + lhs.store(fn, emitExtract(fn, tuple, i)) + } + } + } +} + +// assignStmt emits code to fn for a parallel assignment of rhss to lhss. +// isDef is true if this is a short variable declaration (:=). +// +// Note the similarity with localValueSpec. +// +func (b *builder) assignStmt(fn *Function, lhss, rhss []ast.Expr, isDef bool) { + // Side effects of all LHSs and RHSs must occur in left-to-right order. + lvals := make([]lvalue, len(lhss)) + isZero := make([]bool, len(lhss)) + for i, lhs := range lhss { + var lval lvalue = blank{} + if !isBlankIdent(lhs) { + if isDef { + if obj := fn.Pkg.info.Defs[lhs.(*ast.Ident)]; obj != nil { + fn.addNamedLocal(obj) + isZero[i] = true + } + } + lval = b.addr(fn, lhs, false) // non-escaping + } + lvals[i] = lval + } + if len(lhss) == len(rhss) { + // Simple assignment: x = f() (!isDef) + // Parallel assignment: x, y = f(), g() (!isDef) + // or short var decl: x, y := f(), g() (isDef) + // + // In all cases, the RHSs may refer to the LHSs, + // so we need a storebuf. + var sb storebuf + for i := range rhss { + b.assign(fn, lvals[i], rhss[i], isZero[i], &sb) + } + sb.emit(fn) + } else { + // e.g. x, y = pos() + tuple := b.exprN(fn, rhss[0]) + emitDebugRef(fn, rhss[0], tuple, false) + for i, lval := range lvals { + lval.store(fn, emitExtract(fn, tuple, i)) + } + } +} + +// arrayLen returns the length of the array whose composite literal elements are elts. +func (b *builder) arrayLen(fn *Function, elts []ast.Expr) int64 { + var max int64 = -1 + var i int64 = -1 + for _, e := range elts { + if kv, ok := e.(*ast.KeyValueExpr); ok { + i = b.expr(fn, kv.Key).(*Const).Int64() + } else { + i++ + } + if i > max { + max = i + } + } + return max + 1 +} + +// compLit emits to fn code to initialize a composite literal e at +// address addr with type typ. +// +// Nested composite literals are recursively initialized in place +// where possible. If isZero is true, compLit assumes that addr +// holds the zero value for typ. +// +// Because the elements of a composite literal may refer to the +// variables being updated, as in the second line below, +// x := T{a: 1} +// x = T{a: x.a} +// all the reads must occur before all the writes. Thus all stores to +// loc are emitted to the storebuf sb for later execution. +// +// A CompositeLit may have pointer type only in the recursive (nested) +// case when the type name is implicit. e.g. in []*T{{}}, the inner +// literal has type *T behaves like &T{}. +// In that case, addr must hold a T, not a *T. +// +func (b *builder) compLit(fn *Function, addr Value, e *ast.CompositeLit, isZero bool, sb *storebuf) { + typ := deref(fn.Pkg.typeOf(e)) + switch t := typ.Underlying().(type) { + case *types.Struct: + if !isZero && len(e.Elts) != t.NumFields() { + // memclear + sb.store(&address{addr, e.Lbrace, nil}, + zeroValue(fn, deref(addr.Type()))) + isZero = true + } + for i, e := range e.Elts { + fieldIndex := i + pos := e.Pos() + if kv, ok := e.(*ast.KeyValueExpr); ok { + fname := kv.Key.(*ast.Ident).Name + for i, n := 0, t.NumFields(); i < n; i++ { + sf := t.Field(i) + if sf.Name() == fname { + fieldIndex = i + pos = kv.Colon + e = kv.Value + break + } + } + } + sf := t.Field(fieldIndex) + faddr := &FieldAddr{ + X: addr, + Field: fieldIndex, + } + faddr.setType(types.NewPointer(sf.Type())) + fn.emit(faddr) + b.assign(fn, &address{addr: faddr, pos: pos, expr: e}, e, isZero, sb) + } + + case *types.Array, *types.Slice: + var at *types.Array + var array Value + switch t := t.(type) { + case *types.Slice: + at = types.NewArray(t.Elem(), b.arrayLen(fn, e.Elts)) + alloc := emitNew(fn, at, e.Lbrace) + alloc.Comment = "slicelit" + array = alloc + case *types.Array: + at = t + array = addr + + if !isZero && int64(len(e.Elts)) != at.Len() { + // memclear + sb.store(&address{array, e.Lbrace, nil}, + zeroValue(fn, deref(array.Type()))) + } + } + + var idx *Const + for _, e := range e.Elts { + pos := e.Pos() + if kv, ok := e.(*ast.KeyValueExpr); ok { + idx = b.expr(fn, kv.Key).(*Const) + pos = kv.Colon + e = kv.Value + } else { + var idxval int64 + if idx != nil { + idxval = idx.Int64() + 1 + } + idx = intConst(idxval) + } + iaddr := &IndexAddr{ + X: array, + Index: idx, + } + iaddr.setType(types.NewPointer(at.Elem())) + fn.emit(iaddr) + if t != at { // slice + // backing array is unaliased => storebuf not needed. + b.assign(fn, &address{addr: iaddr, pos: pos, expr: e}, e, true, nil) + } else { + b.assign(fn, &address{addr: iaddr, pos: pos, expr: e}, e, true, sb) + } + } + + if t != at { // slice + s := &Slice{X: array} + s.setPos(e.Lbrace) + s.setType(typ) + sb.store(&address{addr: addr, pos: e.Lbrace, expr: e}, fn.emit(s)) + } + + case *types.Map: + m := &MakeMap{Reserve: intConst(int64(len(e.Elts)))} + m.setPos(e.Lbrace) + m.setType(typ) + fn.emit(m) + for _, e := range e.Elts { + e := e.(*ast.KeyValueExpr) + + // If a key expression in a map literal is itself a + // composite literal, the type may be omitted. + // For example: + // map[*struct{}]bool{{}: true} + // An &-operation may be implied: + // map[*struct{}]bool{&struct{}{}: true} + var key Value + if _, ok := unparen(e.Key).(*ast.CompositeLit); ok && isPointer(t.Key()) { + // A CompositeLit never evaluates to a pointer, + // so if the type of the location is a pointer, + // an &-operation is implied. + key = b.addr(fn, e.Key, true).address(fn) + } else { + key = b.expr(fn, e.Key) + } + + loc := element{ + m: m, + k: emitConv(fn, key, t.Key()), + t: t.Elem(), + pos: e.Colon, + } + + // We call assign() only because it takes care + // of any &-operation required in the recursive + // case, e.g., + // map[int]*struct{}{0: {}} implies &struct{}{}. + // In-place update is of course impossible, + // and no storebuf is needed. + b.assign(fn, &loc, e.Value, true, nil) + } + sb.store(&address{addr: addr, pos: e.Lbrace, expr: e}, m) + + default: + panic("unexpected CompositeLit type: " + t.String()) + } +} + +// switchStmt emits to fn code for the switch statement s, optionally +// labelled by label. +// +func (b *builder) switchStmt(fn *Function, s *ast.SwitchStmt, label *lblock) { + // We treat SwitchStmt like a sequential if-else chain. + // Multiway dispatch can be recovered later by ssautil.Switches() + // to those cases that are free of side effects. + if s.Init != nil { + b.stmt(fn, s.Init) + } + var tag Value = vTrue + if s.Tag != nil { + tag = b.expr(fn, s.Tag) + } + done := fn.newBasicBlock("switch.done") + if label != nil { + label._break = done + } + // We pull the default case (if present) down to the end. + // But each fallthrough label must point to the next + // body block in source order, so we preallocate a + // body block (fallthru) for the next case. + // Unfortunately this makes for a confusing block order. + var dfltBody *[]ast.Stmt + var dfltFallthrough *BasicBlock + var fallthru, dfltBlock *BasicBlock + ncases := len(s.Body.List) + for i, clause := range s.Body.List { + body := fallthru + if body == nil { + body = fn.newBasicBlock("switch.body") // first case only + } + + // Preallocate body block for the next case. + fallthru = done + if i+1 < ncases { + fallthru = fn.newBasicBlock("switch.body") + } + + cc := clause.(*ast.CaseClause) + if cc.List == nil { + // Default case. + dfltBody = &cc.Body + dfltFallthrough = fallthru + dfltBlock = body + continue + } + + var nextCond *BasicBlock + for _, cond := range cc.List { + nextCond = fn.newBasicBlock("switch.next") + // TODO(adonovan): opt: when tag==vTrue, we'd + // get better code if we use b.cond(cond) + // instead of BinOp(EQL, tag, b.expr(cond)) + // followed by If. Don't forget conversions + // though. + cond := emitCompare(fn, token.EQL, tag, b.expr(fn, cond), token.NoPos) + emitIf(fn, cond, body, nextCond) + fn.currentBlock = nextCond + } + fn.currentBlock = body + fn.targets = &targets{ + tail: fn.targets, + _break: done, + _fallthrough: fallthru, + } + b.stmtList(fn, cc.Body) + fn.targets = fn.targets.tail + emitJump(fn, done) + fn.currentBlock = nextCond + } + if dfltBlock != nil { + emitJump(fn, dfltBlock) + fn.currentBlock = dfltBlock + fn.targets = &targets{ + tail: fn.targets, + _break: done, + _fallthrough: dfltFallthrough, + } + b.stmtList(fn, *dfltBody) + fn.targets = fn.targets.tail + } + emitJump(fn, done) + fn.currentBlock = done +} + +// typeSwitchStmt emits to fn code for the type switch statement s, optionally +// labelled by label. +// +func (b *builder) typeSwitchStmt(fn *Function, s *ast.TypeSwitchStmt, label *lblock) { + // We treat TypeSwitchStmt like a sequential if-else chain. + // Multiway dispatch can be recovered later by ssautil.Switches(). + + // Typeswitch lowering: + // + // var x X + // switch y := x.(type) { + // case T1, T2: S1 // >1 (y := x) + // case nil: SN // nil (y := x) + // default: SD // 0 types (y := x) + // case T3: S3 // 1 type (y := x.(T3)) + // } + // + // ...s.Init... + // x := eval x + // .caseT1: + // t1, ok1 := typeswitch,ok x + // if ok1 then goto S1 else goto .caseT2 + // .caseT2: + // t2, ok2 := typeswitch,ok x + // if ok2 then goto S1 else goto .caseNil + // .S1: + // y := x + // ...S1... + // goto done + // .caseNil: + // if t2, ok2 := typeswitch,ok x + // if x == nil then goto SN else goto .caseT3 + // .SN: + // y := x + // ...SN... + // goto done + // .caseT3: + // t3, ok3 := typeswitch,ok x + // if ok3 then goto S3 else goto default + // .S3: + // y := t3 + // ...S3... + // goto done + // .default: + // y := x + // ...SD... + // goto done + // .done: + + if s.Init != nil { + b.stmt(fn, s.Init) + } + + var x Value + switch ass := s.Assign.(type) { + case *ast.ExprStmt: // x.(type) + x = b.expr(fn, unparen(ass.X).(*ast.TypeAssertExpr).X) + case *ast.AssignStmt: // y := x.(type) + x = b.expr(fn, unparen(ass.Rhs[0]).(*ast.TypeAssertExpr).X) + } + + done := fn.newBasicBlock("typeswitch.done") + if label != nil { + label._break = done + } + var default_ *ast.CaseClause + for _, clause := range s.Body.List { + cc := clause.(*ast.CaseClause) + if cc.List == nil { + default_ = cc + continue + } + body := fn.newBasicBlock("typeswitch.body") + var next *BasicBlock + var casetype types.Type + var ti Value // ti, ok := typeassert,ok x + for _, cond := range cc.List { + next = fn.newBasicBlock("typeswitch.next") + casetype = fn.Pkg.typeOf(cond) + var condv Value + if casetype == tUntypedNil { + condv = emitCompare(fn, token.EQL, x, nilConst(x.Type()), token.NoPos) + ti = x + } else { + yok := emitTypeTest(fn, x, casetype, cc.Case) + ti = emitExtract(fn, yok, 0) + condv = emitExtract(fn, yok, 1) + } + emitIf(fn, condv, body, next) + fn.currentBlock = next + } + if len(cc.List) != 1 { + ti = x + } + fn.currentBlock = body + b.typeCaseBody(fn, cc, ti, done) + fn.currentBlock = next + } + if default_ != nil { + b.typeCaseBody(fn, default_, x, done) + } else { + emitJump(fn, done) + } + fn.currentBlock = done +} + +func (b *builder) typeCaseBody(fn *Function, cc *ast.CaseClause, x Value, done *BasicBlock) { + if obj := fn.Pkg.info.Implicits[cc]; obj != nil { + // In a switch y := x.(type), each case clause + // implicitly declares a distinct object y. + // In a single-type case, y has that type. + // In multi-type cases, 'case nil' and default, + // y has the same type as the interface operand. + emitStore(fn, fn.addNamedLocal(obj), x, obj.Pos()) + } + fn.targets = &targets{ + tail: fn.targets, + _break: done, + } + b.stmtList(fn, cc.Body) + fn.targets = fn.targets.tail + emitJump(fn, done) +} + +// selectStmt emits to fn code for the select statement s, optionally +// labelled by label. +// +func (b *builder) selectStmt(fn *Function, s *ast.SelectStmt, label *lblock) { + // A blocking select of a single case degenerates to a + // simple send or receive. + // TODO(adonovan): opt: is this optimization worth its weight? + if len(s.Body.List) == 1 { + clause := s.Body.List[0].(*ast.CommClause) + if clause.Comm != nil { + b.stmt(fn, clause.Comm) + done := fn.newBasicBlock("select.done") + if label != nil { + label._break = done + } + fn.targets = &targets{ + tail: fn.targets, + _break: done, + } + b.stmtList(fn, clause.Body) + fn.targets = fn.targets.tail + emitJump(fn, done) + fn.currentBlock = done + return + } + } + + // First evaluate all channels in all cases, and find + // the directions of each state. + var states []*SelectState + blocking := true + debugInfo := fn.debugInfo() + for _, clause := range s.Body.List { + var st *SelectState + switch comm := clause.(*ast.CommClause).Comm.(type) { + case nil: // default case + blocking = false + continue + + case *ast.SendStmt: // ch<- i + ch := b.expr(fn, comm.Chan) + st = &SelectState{ + Dir: types.SendOnly, + Chan: ch, + Send: emitConv(fn, b.expr(fn, comm.Value), + ch.Type().Underlying().(*types.Chan).Elem()), + Pos: comm.Arrow, + } + if debugInfo { + st.DebugNode = comm + } + + case *ast.AssignStmt: // x := <-ch + recv := unparen(comm.Rhs[0]).(*ast.UnaryExpr) + st = &SelectState{ + Dir: types.RecvOnly, + Chan: b.expr(fn, recv.X), + Pos: recv.OpPos, + } + if debugInfo { + st.DebugNode = recv + } + + case *ast.ExprStmt: // <-ch + recv := unparen(comm.X).(*ast.UnaryExpr) + st = &SelectState{ + Dir: types.RecvOnly, + Chan: b.expr(fn, recv.X), + Pos: recv.OpPos, + } + if debugInfo { + st.DebugNode = recv + } + } + states = append(states, st) + } + + // We dispatch on the (fair) result of Select using a + // sequential if-else chain, in effect: + // + // idx, recvOk, r0...r_n-1 := select(...) + // if idx == 0 { // receive on channel 0 (first receive => r0) + // x, ok := r0, recvOk + // ...state0... + // } else if v == 1 { // send on channel 1 + // ...state1... + // } else { + // ...default... + // } + sel := &Select{ + States: states, + Blocking: blocking, + } + sel.setPos(s.Select) + var vars []*types.Var + vars = append(vars, varIndex, varOk) + for _, st := range states { + if st.Dir == types.RecvOnly { + tElem := st.Chan.Type().Underlying().(*types.Chan).Elem() + vars = append(vars, anonVar(tElem)) + } + } + sel.setType(types.NewTuple(vars...)) + + fn.emit(sel) + idx := emitExtract(fn, sel, 0) + + done := fn.newBasicBlock("select.done") + if label != nil { + label._break = done + } + + var defaultBody *[]ast.Stmt + state := 0 + r := 2 // index in 'sel' tuple of value; increments if st.Dir==RECV + for _, cc := range s.Body.List { + clause := cc.(*ast.CommClause) + if clause.Comm == nil { + defaultBody = &clause.Body + continue + } + body := fn.newBasicBlock("select.body") + next := fn.newBasicBlock("select.next") + emitIf(fn, emitCompare(fn, token.EQL, idx, intConst(int64(state)), token.NoPos), body, next) + fn.currentBlock = body + fn.targets = &targets{ + tail: fn.targets, + _break: done, + } + switch comm := clause.Comm.(type) { + case *ast.ExprStmt: // <-ch + if debugInfo { + v := emitExtract(fn, sel, r) + emitDebugRef(fn, states[state].DebugNode.(ast.Expr), v, false) + } + r++ + + case *ast.AssignStmt: // x := <-states[state].Chan + if comm.Tok == token.DEFINE { + fn.addLocalForIdent(comm.Lhs[0].(*ast.Ident)) + } + x := b.addr(fn, comm.Lhs[0], false) // non-escaping + v := emitExtract(fn, sel, r) + if debugInfo { + emitDebugRef(fn, states[state].DebugNode.(ast.Expr), v, false) + } + x.store(fn, v) + + if len(comm.Lhs) == 2 { // x, ok := ... + if comm.Tok == token.DEFINE { + fn.addLocalForIdent(comm.Lhs[1].(*ast.Ident)) + } + ok := b.addr(fn, comm.Lhs[1], false) // non-escaping + ok.store(fn, emitExtract(fn, sel, 1)) + } + r++ + } + b.stmtList(fn, clause.Body) + fn.targets = fn.targets.tail + emitJump(fn, done) + fn.currentBlock = next + state++ + } + if defaultBody != nil { + fn.targets = &targets{ + tail: fn.targets, + _break: done, + } + b.stmtList(fn, *defaultBody) + fn.targets = fn.targets.tail + } else { + // A blocking select must match some case. + // (This should really be a runtime.errorString, not a string.) + fn.emit(&Panic{ + X: emitConv(fn, stringConst("blocking select matched no case"), tEface), + }) + fn.currentBlock = fn.newBasicBlock("unreachable") + } + emitJump(fn, done) + fn.currentBlock = done +} + +// forStmt emits to fn code for the for statement s, optionally +// labelled by label. +// +func (b *builder) forStmt(fn *Function, s *ast.ForStmt, label *lblock) { + // ...init... + // jump loop + // loop: + // if cond goto body else done + // body: + // ...body... + // jump post + // post: (target of continue) + // ...post... + // jump loop + // done: (target of break) + if s.Init != nil { + b.stmt(fn, s.Init) + } + body := fn.newBasicBlock("for.body") + done := fn.newBasicBlock("for.done") // target of 'break' + loop := body // target of back-edge + if s.Cond != nil { + loop = fn.newBasicBlock("for.loop") + } + cont := loop // target of 'continue' + if s.Post != nil { + cont = fn.newBasicBlock("for.post") + } + if label != nil { + label._break = done + label._continue = cont + } + emitJump(fn, loop) + fn.currentBlock = loop + if loop != body { + b.cond(fn, s.Cond, body, done) + fn.currentBlock = body + } + fn.targets = &targets{ + tail: fn.targets, + _break: done, + _continue: cont, + } + b.stmt(fn, s.Body) + fn.targets = fn.targets.tail + emitJump(fn, cont) + + if s.Post != nil { + fn.currentBlock = cont + b.stmt(fn, s.Post) + emitJump(fn, loop) // back-edge + } + fn.currentBlock = done +} + +// rangeIndexed emits to fn the header for an integer-indexed loop +// over array, *array or slice value x. +// The v result is defined only if tv is non-nil. +// forPos is the position of the "for" token. +// +func (b *builder) rangeIndexed(fn *Function, x Value, tv types.Type, pos token.Pos) (k, v Value, loop, done *BasicBlock) { + // + // length = len(x) + // index = -1 + // loop: (target of continue) + // index++ + // if index < length goto body else done + // body: + // k = index + // v = x[index] + // ...body... + // jump loop + // done: (target of break) + + // Determine number of iterations. + var length Value + if arr, ok := deref(x.Type()).Underlying().(*types.Array); ok { + // For array or *array, the number of iterations is + // known statically thanks to the type. We avoid a + // data dependence upon x, permitting later dead-code + // elimination if x is pure, static unrolling, etc. + // Ranging over a nil *array may have >0 iterations. + // We still generate code for x, in case it has effects. + length = intConst(arr.Len()) + } else { + // length = len(x). + var c Call + c.Call.Value = makeLen(x.Type()) + c.Call.Args = []Value{x} + c.setType(tInt) + length = fn.emit(&c) + } + + index := fn.addLocal(tInt, token.NoPos) + emitStore(fn, index, intConst(-1), pos) + + loop = fn.newBasicBlock("rangeindex.loop") + emitJump(fn, loop) + fn.currentBlock = loop + + incr := &BinOp{ + Op: token.ADD, + X: emitLoad(fn, index), + Y: vOne, + } + incr.setType(tInt) + emitStore(fn, index, fn.emit(incr), pos) + + body := fn.newBasicBlock("rangeindex.body") + done = fn.newBasicBlock("rangeindex.done") + emitIf(fn, emitCompare(fn, token.LSS, incr, length, token.NoPos), body, done) + fn.currentBlock = body + + k = emitLoad(fn, index) + if tv != nil { + switch t := x.Type().Underlying().(type) { + case *types.Array: + instr := &Index{ + X: x, + Index: k, + } + instr.setType(t.Elem()) + v = fn.emit(instr) + + case *types.Pointer: // *array + instr := &IndexAddr{ + X: x, + Index: k, + } + instr.setType(types.NewPointer(t.Elem().Underlying().(*types.Array).Elem())) + v = emitLoad(fn, fn.emit(instr)) + + case *types.Slice: + instr := &IndexAddr{ + X: x, + Index: k, + } + instr.setType(types.NewPointer(t.Elem())) + v = emitLoad(fn, fn.emit(instr)) + + default: + panic("rangeIndexed x:" + t.String()) + } + } + return +} + +// rangeIter emits to fn the header for a loop using +// Range/Next/Extract to iterate over map or string value x. +// tk and tv are the types of the key/value results k and v, or nil +// if the respective component is not wanted. +// +func (b *builder) rangeIter(fn *Function, x Value, tk, tv types.Type, pos token.Pos) (k, v Value, loop, done *BasicBlock) { + // + // it = range x + // loop: (target of continue) + // okv = next it (ok, key, value) + // ok = extract okv #0 + // if ok goto body else done + // body: + // k = extract okv #1 + // v = extract okv #2 + // ...body... + // jump loop + // done: (target of break) + // + + if tk == nil { + tk = tInvalid + } + if tv == nil { + tv = tInvalid + } + + rng := &Range{X: x} + rng.setPos(pos) + rng.setType(tRangeIter) + it := fn.emit(rng) + + loop = fn.newBasicBlock("rangeiter.loop") + emitJump(fn, loop) + fn.currentBlock = loop + + _, isString := x.Type().Underlying().(*types.Basic) + + okv := &Next{ + Iter: it, + IsString: isString, + } + okv.setType(types.NewTuple( + varOk, + newVar("k", tk), + newVar("v", tv), + )) + fn.emit(okv) + + body := fn.newBasicBlock("rangeiter.body") + done = fn.newBasicBlock("rangeiter.done") + emitIf(fn, emitExtract(fn, okv, 0), body, done) + fn.currentBlock = body + + if tk != tInvalid { + k = emitExtract(fn, okv, 1) + } + if tv != tInvalid { + v = emitExtract(fn, okv, 2) + } + return +} + +// rangeChan emits to fn the header for a loop that receives from +// channel x until it fails. +// tk is the channel's element type, or nil if the k result is +// not wanted +// pos is the position of the '=' or ':=' token. +// +func (b *builder) rangeChan(fn *Function, x Value, tk types.Type, pos token.Pos) (k Value, loop, done *BasicBlock) { + // + // loop: (target of continue) + // ko = <-x (key, ok) + // ok = extract ko #1 + // if ok goto body else done + // body: + // k = extract ko #0 + // ... + // goto loop + // done: (target of break) + + loop = fn.newBasicBlock("rangechan.loop") + emitJump(fn, loop) + fn.currentBlock = loop + recv := &UnOp{ + Op: token.ARROW, + X: x, + CommaOk: true, + } + recv.setPos(pos) + recv.setType(types.NewTuple( + newVar("k", x.Type().Underlying().(*types.Chan).Elem()), + varOk, + )) + ko := fn.emit(recv) + body := fn.newBasicBlock("rangechan.body") + done = fn.newBasicBlock("rangechan.done") + emitIf(fn, emitExtract(fn, ko, 1), body, done) + fn.currentBlock = body + if tk != nil { + k = emitExtract(fn, ko, 0) + } + return +} + +// rangeStmt emits to fn code for the range statement s, optionally +// labelled by label. +// +func (b *builder) rangeStmt(fn *Function, s *ast.RangeStmt, label *lblock) { + var tk, tv types.Type + if s.Key != nil && !isBlankIdent(s.Key) { + tk = fn.Pkg.typeOf(s.Key) + } + if s.Value != nil && !isBlankIdent(s.Value) { + tv = fn.Pkg.typeOf(s.Value) + } + + // If iteration variables are defined (:=), this + // occurs once outside the loop. + // + // Unlike a short variable declaration, a RangeStmt + // using := never redeclares an existing variable; it + // always creates a new one. + if s.Tok == token.DEFINE { + if tk != nil { + fn.addLocalForIdent(s.Key.(*ast.Ident)) + } + if tv != nil { + fn.addLocalForIdent(s.Value.(*ast.Ident)) + } + } + + x := b.expr(fn, s.X) + + var k, v Value + var loop, done *BasicBlock + switch rt := x.Type().Underlying().(type) { + case *types.Slice, *types.Array, *types.Pointer: // *array + k, v, loop, done = b.rangeIndexed(fn, x, tv, s.For) + + case *types.Chan: + k, loop, done = b.rangeChan(fn, x, tk, s.For) + + case *types.Map, *types.Basic: // string + k, v, loop, done = b.rangeIter(fn, x, tk, tv, s.For) + + default: + panic("Cannot range over: " + rt.String()) + } + + // Evaluate both LHS expressions before we update either. + var kl, vl lvalue + if tk != nil { + kl = b.addr(fn, s.Key, false) // non-escaping + } + if tv != nil { + vl = b.addr(fn, s.Value, false) // non-escaping + } + if tk != nil { + kl.store(fn, k) + } + if tv != nil { + vl.store(fn, v) + } + + if label != nil { + label._break = done + label._continue = loop + } + + fn.targets = &targets{ + tail: fn.targets, + _break: done, + _continue: loop, + } + b.stmt(fn, s.Body) + fn.targets = fn.targets.tail + emitJump(fn, loop) // back-edge + fn.currentBlock = done +} + +// stmt lowers statement s to SSA form, emitting code to fn. +func (b *builder) stmt(fn *Function, _s ast.Stmt) { + // The label of the current statement. If non-nil, its _goto + // target is always set; its _break and _continue are set only + // within the body of switch/typeswitch/select/for/range. + // It is effectively an additional default-nil parameter of stmt(). + var label *lblock +start: + switch s := _s.(type) { + case *ast.EmptyStmt: + // ignore. (Usually removed by gofmt.) + + case *ast.DeclStmt: // Con, Var or Typ + d := s.Decl.(*ast.GenDecl) + if d.Tok == token.VAR { + for _, spec := range d.Specs { + if vs, ok := spec.(*ast.ValueSpec); ok { + b.localValueSpec(fn, vs) + } + } + } + + case *ast.LabeledStmt: + label = fn.labelledBlock(s.Label) + emitJump(fn, label._goto) + fn.currentBlock = label._goto + _s = s.Stmt + goto start // effectively: tailcall stmt(fn, s.Stmt, label) + + case *ast.ExprStmt: + b.expr(fn, s.X) + + case *ast.SendStmt: + fn.emit(&Send{ + Chan: b.expr(fn, s.Chan), + X: emitConv(fn, b.expr(fn, s.Value), + fn.Pkg.typeOf(s.Chan).Underlying().(*types.Chan).Elem()), + pos: s.Arrow, + }) + + case *ast.IncDecStmt: + op := token.ADD + if s.Tok == token.DEC { + op = token.SUB + } + loc := b.addr(fn, s.X, false) + b.assignOp(fn, loc, NewConst(exact.MakeInt64(1), loc.typ()), op, s.Pos()) + + case *ast.AssignStmt: + switch s.Tok { + case token.ASSIGN, token.DEFINE: + b.assignStmt(fn, s.Lhs, s.Rhs, s.Tok == token.DEFINE) + + default: // +=, etc. + op := s.Tok + token.ADD - token.ADD_ASSIGN + b.assignOp(fn, b.addr(fn, s.Lhs[0], false), b.expr(fn, s.Rhs[0]), op, s.Pos()) + } + + case *ast.GoStmt: + // The "intrinsics" new/make/len/cap are forbidden here. + // panic is treated like an ordinary function call. + v := Go{pos: s.Go} + b.setCall(fn, s.Call, &v.Call) + fn.emit(&v) + + case *ast.DeferStmt: + // The "intrinsics" new/make/len/cap are forbidden here. + // panic is treated like an ordinary function call. + v := Defer{pos: s.Defer} + b.setCall(fn, s.Call, &v.Call) + fn.emit(&v) + + // A deferred call can cause recovery from panic, + // and control resumes at the Recover block. + createRecoverBlock(fn) + + case *ast.ReturnStmt: + var results []Value + if len(s.Results) == 1 && fn.Signature.Results().Len() > 1 { + // Return of one expression in a multi-valued function. + tuple := b.exprN(fn, s.Results[0]) + ttuple := tuple.Type().(*types.Tuple) + for i, n := 0, ttuple.Len(); i < n; i++ { + results = append(results, + emitConv(fn, emitExtract(fn, tuple, i), + fn.Signature.Results().At(i).Type())) + } + } else { + // 1:1 return, or no-arg return in non-void function. + for i, r := range s.Results { + v := emitConv(fn, b.expr(fn, r), fn.Signature.Results().At(i).Type()) + results = append(results, v) + } + } + if fn.namedResults != nil { + // Function has named result parameters (NRPs). + // Perform parallel assignment of return operands to NRPs. + for i, r := range results { + emitStore(fn, fn.namedResults[i], r, s.Return) + } + } + // Run function calls deferred in this + // function when explicitly returning from it. + fn.emit(new(RunDefers)) + if fn.namedResults != nil { + // Reload NRPs to form the result tuple. + results = results[:0] + for _, r := range fn.namedResults { + results = append(results, emitLoad(fn, r)) + } + } + fn.emit(&Return{Results: results, pos: s.Return}) + fn.currentBlock = fn.newBasicBlock("unreachable") + + case *ast.BranchStmt: + var block *BasicBlock + switch s.Tok { + case token.BREAK: + if s.Label != nil { + block = fn.labelledBlock(s.Label)._break + } else { + for t := fn.targets; t != nil && block == nil; t = t.tail { + block = t._break + } + } + + case token.CONTINUE: + if s.Label != nil { + block = fn.labelledBlock(s.Label)._continue + } else { + for t := fn.targets; t != nil && block == nil; t = t.tail { + block = t._continue + } + } + + case token.FALLTHROUGH: + for t := fn.targets; t != nil && block == nil; t = t.tail { + block = t._fallthrough + } + + case token.GOTO: + block = fn.labelledBlock(s.Label)._goto + } + emitJump(fn, block) + fn.currentBlock = fn.newBasicBlock("unreachable") + + case *ast.BlockStmt: + b.stmtList(fn, s.List) + + case *ast.IfStmt: + if s.Init != nil { + b.stmt(fn, s.Init) + } + then := fn.newBasicBlock("if.then") + done := fn.newBasicBlock("if.done") + els := done + if s.Else != nil { + els = fn.newBasicBlock("if.else") + } + b.cond(fn, s.Cond, then, els) + fn.currentBlock = then + b.stmt(fn, s.Body) + emitJump(fn, done) + + if s.Else != nil { + fn.currentBlock = els + b.stmt(fn, s.Else) + emitJump(fn, done) + } + + fn.currentBlock = done + + case *ast.SwitchStmt: + b.switchStmt(fn, s, label) + + case *ast.TypeSwitchStmt: + b.typeSwitchStmt(fn, s, label) + + case *ast.SelectStmt: + b.selectStmt(fn, s, label) + + case *ast.ForStmt: + b.forStmt(fn, s, label) + + case *ast.RangeStmt: + b.rangeStmt(fn, s, label) + + default: + panic(fmt.Sprintf("unexpected statement kind: %T", s)) + } +} + +// buildFunction builds SSA code for the body of function fn. Idempotent. +func (b *builder) buildFunction(fn *Function) { + if fn.Blocks != nil { + return // building already started + } + + var recvField *ast.FieldList + var body *ast.BlockStmt + var functype *ast.FuncType + switch n := fn.syntax.(type) { + case nil: + return // not a Go source function. (Synthetic, or from object file.) + case *ast.FuncDecl: + functype = n.Type + recvField = n.Recv + body = n.Body + case *ast.FuncLit: + functype = n.Type + body = n.Body + default: + panic(n) + } + + if body == nil { + // External function. + if fn.Params == nil { + // This condition ensures we add a non-empty + // params list once only, but we may attempt + // the degenerate empty case repeatedly. + // TODO(adonovan): opt: don't do that. + + // We set Function.Params even though there is no body + // code to reference them. This simplifies clients. + if recv := fn.Signature.Recv(); recv != nil { + fn.addParamObj(recv) + } + params := fn.Signature.Params() + for i, n := 0, params.Len(); i < n; i++ { + fn.addParamObj(params.At(i)) + } + } + return + } + if fn.Prog.mode&LogSource != 0 { + defer logStack("build function %s @ %s", fn, fn.Prog.Fset.Position(fn.pos))() + } + fn.startBody() + fn.createSyntacticParams(recvField, functype) + b.stmt(fn, body) + if cb := fn.currentBlock; cb != nil && (cb == fn.Blocks[0] || cb == fn.Recover || cb.Preds != nil) { + // Control fell off the end of the function's body block. + // + // Block optimizations eliminate the current block, if + // unreachable. It is a builder invariant that + // if this no-arg return is ill-typed for + // fn.Signature.Results, this block must be + // unreachable. The sanity checker checks this. + fn.emit(new(RunDefers)) + fn.emit(new(Return)) + } + fn.finishBody() +} + +// buildFuncDecl builds SSA code for the function or method declared +// by decl in package pkg. +// +func (b *builder) buildFuncDecl(pkg *Package, decl *ast.FuncDecl) { + id := decl.Name + if isBlankIdent(id) { + return // discard + } + fn := pkg.values[pkg.info.Defs[id]].(*Function) + if decl.Recv == nil && id.Name == "init" { + var v Call + v.Call.Value = fn + v.setType(types.NewTuple()) + pkg.init.emit(&v) + } + b.buildFunction(fn) +} + +// Build calls Package.Build for each package in prog. +// Building occurs in parallel unless the BuildSerially mode flag was set. +// +// Build is intended for whole-program analysis; a typical compiler +// need only build a single package. +// +// Build is idempotent and thread-safe. +// +func (prog *Program) Build() { + var wg sync.WaitGroup + for _, p := range prog.packages { + if prog.mode&BuildSerially != 0 { + p.Build() + } else { + wg.Add(1) + go func(p *Package) { + p.Build() + wg.Done() + }(p) + } + } + wg.Wait() +} + +// Build builds SSA code for all functions and vars in package p. +// +// Precondition: CreatePackage must have been called for all of p's +// direct imports (and hence its direct imports must have been +// error-free). +// +// Build is idempotent and thread-safe. +// +func (p *Package) Build() { p.buildOnce.Do(p.build) } + +func (p *Package) build() { + if p.info == nil { + return // synthetic package, e.g. "testmain" + } + + // Ensure we have runtime type info for all exported members. + // TODO(adonovan): ideally belongs in memberFromObject, but + // that would require package creation in topological order. + for name, mem := range p.Members { + if ast.IsExported(name) { + p.Prog.needMethodsOf(mem.Type()) + } + } + if p.Prog.mode&LogSource != 0 { + defer logStack("build %s", p)() + } + init := p.init + init.startBody() + + var done *BasicBlock + + if p.Prog.mode&BareInits == 0 { + // Make init() skip if package is already initialized. + initguard := p.Var("init$guard") + doinit := init.newBasicBlock("init.start") + done = init.newBasicBlock("init.done") + emitIf(init, emitLoad(init, initguard), done, doinit) + init.currentBlock = doinit + emitStore(init, initguard, vTrue, token.NoPos) + + // Call the init() function of each package we import. + for _, pkg := range p.Pkg.Imports() { + prereq := p.Prog.packages[pkg] + if prereq == nil { + panic(fmt.Sprintf("Package(%q).Build(): unsatisfied import: Program.CreatePackage(%q) was not called", p.Pkg.Path(), pkg.Path())) + } + var v Call + v.Call.Value = prereq.init + v.Call.pos = init.pos + v.setType(types.NewTuple()) + init.emit(&v) + } + } + + var b builder + + // Initialize package-level vars in correct order. + for _, varinit := range p.info.InitOrder { + if init.Prog.mode&LogSource != 0 { + fmt.Fprintf(os.Stderr, "build global initializer %v @ %s\n", + varinit.Lhs, p.Prog.Fset.Position(varinit.Rhs.Pos())) + } + if len(varinit.Lhs) == 1 { + // 1:1 initialization: var x, y = a(), b() + var lval lvalue + if v := varinit.Lhs[0]; v.Name() != "_" { + lval = &address{addr: p.values[v].(*Global), pos: v.Pos()} + } else { + lval = blank{} + } + b.assign(init, lval, varinit.Rhs, true, nil) + } else { + // n:1 initialization: var x, y := f() + tuple := b.exprN(init, varinit.Rhs) + for i, v := range varinit.Lhs { + if v.Name() == "_" { + continue + } + emitStore(init, p.values[v].(*Global), emitExtract(init, tuple, i), v.Pos()) + } + } + } + + // Build all package-level functions, init functions + // and methods, including unreachable/blank ones. + // We build them in source order, but it's not significant. + for _, file := range p.files { + for _, decl := range file.Decls { + if decl, ok := decl.(*ast.FuncDecl); ok { + b.buildFuncDecl(p, decl) + } + } + } + + // Finish up init(). + if p.Prog.mode&BareInits == 0 { + emitJump(init, done) + init.currentBlock = done + } + init.emit(new(Return)) + init.finishBody() + + p.info = nil // We no longer need ASTs or go/types deductions. + + if p.Prog.mode&SanityCheckFunctions != 0 { + sanityCheckPackage(p) + } +} + +// Like ObjectOf, but panics instead of returning nil. +// Only valid during p's create and build phases. +func (p *Package) objectOf(id *ast.Ident) types.Object { + if o := p.info.ObjectOf(id); o != nil { + return o + } + panic(fmt.Sprintf("no types.Object for ast.Ident %s @ %s", + id.Name, p.Prog.Fset.Position(id.Pos()))) +} + +// Like TypeOf, but panics instead of returning nil. +// Only valid during p's create and build phases. +func (p *Package) typeOf(e ast.Expr) types.Type { + if T := p.info.TypeOf(e); T != nil { + return T + } + panic(fmt.Sprintf("no type for %T @ %s", + e, p.Prog.Fset.Position(e.Pos()))) +} diff --git a/vendor/honnef.co/go/tools/ssa/const.go b/vendor/honnef.co/go/tools/ssa/const.go new file mode 100644 index 0000000000..ca99adc3f1 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/const.go @@ -0,0 +1,169 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file defines the Const SSA value type. + +import ( + "fmt" + exact "go/constant" + "go/token" + "go/types" + "strconv" +) + +// NewConst returns a new constant of the specified value and type. +// val must be valid according to the specification of Const.Value. +// +func NewConst(val exact.Value, typ types.Type) *Const { + return &Const{typ, val} +} + +// intConst returns an 'int' constant that evaluates to i. +// (i is an int64 in case the host is narrower than the target.) +func intConst(i int64) *Const { + return NewConst(exact.MakeInt64(i), tInt) +} + +// nilConst returns a nil constant of the specified type, which may +// be any reference type, including interfaces. +// +func nilConst(typ types.Type) *Const { + return NewConst(nil, typ) +} + +// stringConst returns a 'string' constant that evaluates to s. +func stringConst(s string) *Const { + return NewConst(exact.MakeString(s), tString) +} + +// zeroConst returns a new "zero" constant of the specified type, +// which must not be an array or struct type: the zero values of +// aggregates are well-defined but cannot be represented by Const. +// +func zeroConst(t types.Type) *Const { + switch t := t.(type) { + case *types.Basic: + switch { + case t.Info()&types.IsBoolean != 0: + return NewConst(exact.MakeBool(false), t) + case t.Info()&types.IsNumeric != 0: + return NewConst(exact.MakeInt64(0), t) + case t.Info()&types.IsString != 0: + return NewConst(exact.MakeString(""), t) + case t.Kind() == types.UnsafePointer: + fallthrough + case t.Kind() == types.UntypedNil: + return nilConst(t) + default: + panic(fmt.Sprint("zeroConst for unexpected type:", t)) + } + case *types.Pointer, *types.Slice, *types.Interface, *types.Chan, *types.Map, *types.Signature: + return nilConst(t) + case *types.Named: + return NewConst(zeroConst(t.Underlying()).Value, t) + case *types.Array, *types.Struct, *types.Tuple: + panic(fmt.Sprint("zeroConst applied to aggregate:", t)) + } + panic(fmt.Sprint("zeroConst: unexpected ", t)) +} + +func (c *Const) RelString(from *types.Package) string { + var s string + if c.Value == nil { + s = "nil" + } else if c.Value.Kind() == exact.String { + s = exact.StringVal(c.Value) + const max = 20 + // TODO(adonovan): don't cut a rune in half. + if len(s) > max { + s = s[:max-3] + "..." // abbreviate + } + s = strconv.Quote(s) + } else { + s = c.Value.String() + } + return s + ":" + relType(c.Type(), from) +} + +func (c *Const) Name() string { + return c.RelString(nil) +} + +func (c *Const) String() string { + return c.Name() +} + +func (c *Const) Type() types.Type { + return c.typ +} + +func (c *Const) Referrers() *[]Instruction { + return nil +} + +func (c *Const) Parent() *Function { return nil } + +func (c *Const) Pos() token.Pos { + return token.NoPos +} + +// IsNil returns true if this constant represents a typed or untyped nil value. +func (c *Const) IsNil() bool { + return c.Value == nil +} + +// TODO(adonovan): move everything below into honnef.co/go/tools/ssa/interp. + +// Int64 returns the numeric value of this constant truncated to fit +// a signed 64-bit integer. +// +func (c *Const) Int64() int64 { + switch x := exact.ToInt(c.Value); x.Kind() { + case exact.Int: + if i, ok := exact.Int64Val(x); ok { + return i + } + return 0 + case exact.Float: + f, _ := exact.Float64Val(x) + return int64(f) + } + panic(fmt.Sprintf("unexpected constant value: %T", c.Value)) +} + +// Uint64 returns the numeric value of this constant truncated to fit +// an unsigned 64-bit integer. +// +func (c *Const) Uint64() uint64 { + switch x := exact.ToInt(c.Value); x.Kind() { + case exact.Int: + if u, ok := exact.Uint64Val(x); ok { + return u + } + return 0 + case exact.Float: + f, _ := exact.Float64Val(x) + return uint64(f) + } + panic(fmt.Sprintf("unexpected constant value: %T", c.Value)) +} + +// Float64 returns the numeric value of this constant truncated to fit +// a float64. +// +func (c *Const) Float64() float64 { + f, _ := exact.Float64Val(c.Value) + return f +} + +// Complex128 returns the complex value of this constant truncated to +// fit a complex128. +// +func (c *Const) Complex128() complex128 { + re, _ := exact.Float64Val(exact.Real(c.Value)) + im, _ := exact.Float64Val(exact.Imag(c.Value)) + return complex(re, im) +} diff --git a/vendor/honnef.co/go/tools/ssa/create.go b/vendor/honnef.co/go/tools/ssa/create.go new file mode 100644 index 0000000000..69ac12b1bf --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/create.go @@ -0,0 +1,263 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file implements the CREATE phase of SSA construction. +// See builder.go for explanation. + +import ( + "fmt" + "go/ast" + "go/token" + "go/types" + "os" + "sync" + + "golang.org/x/tools/go/types/typeutil" +) + +// NewProgram returns a new SSA Program. +// +// mode controls diagnostics and checking during SSA construction. +// +func NewProgram(fset *token.FileSet, mode BuilderMode) *Program { + prog := &Program{ + Fset: fset, + imported: make(map[string]*Package), + packages: make(map[*types.Package]*Package), + thunks: make(map[selectionKey]*Function), + bounds: make(map[*types.Func]*Function), + mode: mode, + } + + h := typeutil.MakeHasher() // protected by methodsMu, in effect + prog.methodSets.SetHasher(h) + prog.canon.SetHasher(h) + + return prog +} + +// memberFromObject populates package pkg with a member for the +// typechecker object obj. +// +// For objects from Go source code, syntax is the associated syntax +// tree (for funcs and vars only); it will be used during the build +// phase. +// +func memberFromObject(pkg *Package, obj types.Object, syntax ast.Node) { + name := obj.Name() + switch obj := obj.(type) { + case *types.Builtin: + if pkg.Pkg != types.Unsafe { + panic("unexpected builtin object: " + obj.String()) + } + + case *types.TypeName: + pkg.Members[name] = &Type{ + object: obj, + pkg: pkg, + } + + case *types.Const: + c := &NamedConst{ + object: obj, + Value: NewConst(obj.Val(), obj.Type()), + pkg: pkg, + } + pkg.values[obj] = c.Value + pkg.Members[name] = c + + case *types.Var: + g := &Global{ + Pkg: pkg, + name: name, + object: obj, + typ: types.NewPointer(obj.Type()), // address + pos: obj.Pos(), + } + pkg.values[obj] = g + pkg.Members[name] = g + + case *types.Func: + sig := obj.Type().(*types.Signature) + if sig.Recv() == nil && name == "init" { + pkg.ninit++ + name = fmt.Sprintf("init#%d", pkg.ninit) + } + fn := &Function{ + name: name, + object: obj, + Signature: sig, + syntax: syntax, + pos: obj.Pos(), + Pkg: pkg, + Prog: pkg.Prog, + } + if syntax == nil { + fn.Synthetic = "loaded from gc object file" + } + + pkg.values[obj] = fn + if sig.Recv() == nil { + pkg.Members[name] = fn // package-level function + } + + default: // (incl. *types.Package) + panic("unexpected Object type: " + obj.String()) + } +} + +// membersFromDecl populates package pkg with members for each +// typechecker object (var, func, const or type) associated with the +// specified decl. +// +func membersFromDecl(pkg *Package, decl ast.Decl) { + switch decl := decl.(type) { + case *ast.GenDecl: // import, const, type or var + switch decl.Tok { + case token.CONST: + for _, spec := range decl.Specs { + for _, id := range spec.(*ast.ValueSpec).Names { + if !isBlankIdent(id) { + memberFromObject(pkg, pkg.info.Defs[id], nil) + } + } + } + + case token.VAR: + for _, spec := range decl.Specs { + for _, id := range spec.(*ast.ValueSpec).Names { + if !isBlankIdent(id) { + memberFromObject(pkg, pkg.info.Defs[id], spec) + } + } + } + + case token.TYPE: + for _, spec := range decl.Specs { + id := spec.(*ast.TypeSpec).Name + if !isBlankIdent(id) { + memberFromObject(pkg, pkg.info.Defs[id], nil) + } + } + } + + case *ast.FuncDecl: + id := decl.Name + if !isBlankIdent(id) { + memberFromObject(pkg, pkg.info.Defs[id], decl) + } + } +} + +// CreatePackage constructs and returns an SSA Package from the +// specified type-checked, error-free file ASTs, and populates its +// Members mapping. +// +// importable determines whether this package should be returned by a +// subsequent call to ImportedPackage(pkg.Path()). +// +// The real work of building SSA form for each function is not done +// until a subsequent call to Package.Build(). +// +func (prog *Program) CreatePackage(pkg *types.Package, files []*ast.File, info *types.Info, importable bool) *Package { + p := &Package{ + Prog: prog, + Members: make(map[string]Member), + values: make(map[types.Object]Value), + Pkg: pkg, + info: info, // transient (CREATE and BUILD phases) + files: files, // transient (CREATE and BUILD phases) + } + + // Add init() function. + p.init = &Function{ + name: "init", + Signature: new(types.Signature), + Synthetic: "package initializer", + Pkg: p, + Prog: prog, + } + p.Members[p.init.name] = p.init + + // CREATE phase. + // Allocate all package members: vars, funcs, consts and types. + if len(files) > 0 { + // Go source package. + for _, file := range files { + for _, decl := range file.Decls { + membersFromDecl(p, decl) + } + } + } else { + // GC-compiled binary package (or "unsafe") + // No code. + // No position information. + scope := p.Pkg.Scope() + for _, name := range scope.Names() { + obj := scope.Lookup(name) + memberFromObject(p, obj, nil) + if obj, ok := obj.(*types.TypeName); ok { + if named, ok := obj.Type().(*types.Named); ok { + for i, n := 0, named.NumMethods(); i < n; i++ { + memberFromObject(p, named.Method(i), nil) + } + } + } + } + } + + if prog.mode&BareInits == 0 { + // Add initializer guard variable. + initguard := &Global{ + Pkg: p, + name: "init$guard", + typ: types.NewPointer(tBool), + } + p.Members[initguard.Name()] = initguard + } + + if prog.mode&GlobalDebug != 0 { + p.SetDebugMode(true) + } + + if prog.mode&PrintPackages != 0 { + printMu.Lock() + p.WriteTo(os.Stdout) + printMu.Unlock() + } + + if importable { + prog.imported[p.Pkg.Path()] = p + } + prog.packages[p.Pkg] = p + + return p +} + +// printMu serializes printing of Packages/Functions to stdout. +var printMu sync.Mutex + +// AllPackages returns a new slice containing all packages in the +// program prog in unspecified order. +// +func (prog *Program) AllPackages() []*Package { + pkgs := make([]*Package, 0, len(prog.packages)) + for _, pkg := range prog.packages { + pkgs = append(pkgs, pkg) + } + return pkgs +} + +// ImportedPackage returns the importable SSA Package whose import +// path is path, or nil if no such SSA package has been created. +// +// Not all packages are importable. For example, no import +// declaration can resolve to the x_test package created by 'go test' +// or the ad-hoc main package created 'go build foo.go'. +// +func (prog *Program) ImportedPackage(path string) *Package { + return prog.imported[path] +} diff --git a/vendor/honnef.co/go/tools/ssa/doc.go b/vendor/honnef.co/go/tools/ssa/doc.go new file mode 100644 index 0000000000..57474dd202 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/doc.go @@ -0,0 +1,123 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package ssa defines a representation of the elements of Go programs +// (packages, types, functions, variables and constants) using a +// static single-assignment (SSA) form intermediate representation +// (IR) for the bodies of functions. +// +// THIS INTERFACE IS EXPERIMENTAL AND IS LIKELY TO CHANGE. +// +// For an introduction to SSA form, see +// http://en.wikipedia.org/wiki/Static_single_assignment_form. +// This page provides a broader reading list: +// http://www.dcs.gla.ac.uk/~jsinger/ssa.html. +// +// The level of abstraction of the SSA form is intentionally close to +// the source language to facilitate construction of source analysis +// tools. It is not intended for machine code generation. +// +// All looping, branching and switching constructs are replaced with +// unstructured control flow. Higher-level control flow constructs +// such as multi-way branch can be reconstructed as needed; see +// ssautil.Switches() for an example. +// +// To construct an SSA-form program, call ssautil.CreateProgram on a +// loader.Program, a set of type-checked packages created from +// parsed Go source files. The resulting ssa.Program contains all the +// packages and their members, but SSA code is not created for +// function bodies until a subsequent call to (*Package).Build. +// +// The builder initially builds a naive SSA form in which all local +// variables are addresses of stack locations with explicit loads and +// stores. Registerisation of eligible locals and φ-node insertion +// using dominance and dataflow are then performed as a second pass +// called "lifting" to improve the accuracy and performance of +// subsequent analyses; this pass can be skipped by setting the +// NaiveForm builder flag. +// +// The primary interfaces of this package are: +// +// - Member: a named member of a Go package. +// - Value: an expression that yields a value. +// - Instruction: a statement that consumes values and performs computation. +// - Node: a Value or Instruction (emphasizing its membership in the SSA value graph) +// +// A computation that yields a result implements both the Value and +// Instruction interfaces. The following table shows for each +// concrete type which of these interfaces it implements. +// +// Value? Instruction? Member? +// *Alloc ✔ ✔ +// *BinOp ✔ ✔ +// *Builtin ✔ +// *Call ✔ ✔ +// *ChangeInterface ✔ ✔ +// *ChangeType ✔ ✔ +// *Const ✔ +// *Convert ✔ ✔ +// *DebugRef ✔ +// *Defer ✔ +// *Extract ✔ ✔ +// *Field ✔ ✔ +// *FieldAddr ✔ ✔ +// *FreeVar ✔ +// *Function ✔ ✔ (func) +// *Global ✔ ✔ (var) +// *Go ✔ +// *If ✔ +// *Index ✔ ✔ +// *IndexAddr ✔ ✔ +// *Jump ✔ +// *Lookup ✔ ✔ +// *MakeChan ✔ ✔ +// *MakeClosure ✔ ✔ +// *MakeInterface ✔ ✔ +// *MakeMap ✔ ✔ +// *MakeSlice ✔ ✔ +// *MapUpdate ✔ +// *NamedConst ✔ (const) +// *Next ✔ ✔ +// *Panic ✔ +// *Parameter ✔ +// *Phi ✔ ✔ +// *Range ✔ ✔ +// *Return ✔ +// *RunDefers ✔ +// *Select ✔ ✔ +// *Send ✔ +// *Slice ✔ ✔ +// *Store ✔ +// *Type ✔ (type) +// *TypeAssert ✔ ✔ +// *UnOp ✔ ✔ +// +// Other key types in this package include: Program, Package, Function +// and BasicBlock. +// +// The program representation constructed by this package is fully +// resolved internally, i.e. it does not rely on the names of Values, +// Packages, Functions, Types or BasicBlocks for the correct +// interpretation of the program. Only the identities of objects and +// the topology of the SSA and type graphs are semantically +// significant. (There is one exception: Ids, used to identify field +// and method names, contain strings.) Avoidance of name-based +// operations simplifies the implementation of subsequent passes and +// can make them very efficient. Many objects are nonetheless named +// to aid in debugging, but it is not essential that the names be +// either accurate or unambiguous. The public API exposes a number of +// name-based maps for client convenience. +// +// The ssa/ssautil package provides various utilities that depend only +// on the public API of this package. +// +// TODO(adonovan): Consider the exceptional control-flow implications +// of defer and recover(). +// +// TODO(adonovan): write a how-to document for all the various cases +// of trying to determine corresponding elements across the four +// domains of source locations, ast.Nodes, types.Objects, +// ssa.Values/Instructions. +// +package ssa // import "honnef.co/go/tools/ssa" diff --git a/vendor/honnef.co/go/tools/ssa/dom.go b/vendor/honnef.co/go/tools/ssa/dom.go new file mode 100644 index 0000000000..12ef4308f3 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/dom.go @@ -0,0 +1,341 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file defines algorithms related to dominance. + +// Dominator tree construction ---------------------------------------- +// +// We use the algorithm described in Lengauer & Tarjan. 1979. A fast +// algorithm for finding dominators in a flowgraph. +// http://doi.acm.org/10.1145/357062.357071 +// +// We also apply the optimizations to SLT described in Georgiadis et +// al, Finding Dominators in Practice, JGAA 2006, +// http://jgaa.info/accepted/2006/GeorgiadisTarjanWerneck2006.10.1.pdf +// to avoid the need for buckets of size > 1. + +import ( + "bytes" + "fmt" + "math/big" + "os" + "sort" +) + +// Idom returns the block that immediately dominates b: +// its parent in the dominator tree, if any. +// Neither the entry node (b.Index==0) nor recover node +// (b==b.Parent().Recover()) have a parent. +// +func (b *BasicBlock) Idom() *BasicBlock { return b.dom.idom } + +// Dominees returns the list of blocks that b immediately dominates: +// its children in the dominator tree. +// +func (b *BasicBlock) Dominees() []*BasicBlock { return b.dom.children } + +// Dominates reports whether b dominates c. +func (b *BasicBlock) Dominates(c *BasicBlock) bool { + return b.dom.pre <= c.dom.pre && c.dom.post <= b.dom.post +} + +type byDomPreorder []*BasicBlock + +func (a byDomPreorder) Len() int { return len(a) } +func (a byDomPreorder) Swap(i, j int) { a[i], a[j] = a[j], a[i] } +func (a byDomPreorder) Less(i, j int) bool { return a[i].dom.pre < a[j].dom.pre } + +// DomPreorder returns a new slice containing the blocks of f in +// dominator tree preorder. +// +func (f *Function) DomPreorder() []*BasicBlock { + n := len(f.Blocks) + order := make(byDomPreorder, n, n) + copy(order, f.Blocks) + sort.Sort(order) + return order +} + +// domInfo contains a BasicBlock's dominance information. +type domInfo struct { + idom *BasicBlock // immediate dominator (parent in domtree) + children []*BasicBlock // nodes immediately dominated by this one + pre, post int32 // pre- and post-order numbering within domtree +} + +// ltState holds the working state for Lengauer-Tarjan algorithm +// (during which domInfo.pre is repurposed for CFG DFS preorder number). +type ltState struct { + // Each slice is indexed by b.Index. + sdom []*BasicBlock // b's semidominator + parent []*BasicBlock // b's parent in DFS traversal of CFG + ancestor []*BasicBlock // b's ancestor with least sdom +} + +// dfs implements the depth-first search part of the LT algorithm. +func (lt *ltState) dfs(v *BasicBlock, i int32, preorder []*BasicBlock) int32 { + preorder[i] = v + v.dom.pre = i // For now: DFS preorder of spanning tree of CFG + i++ + lt.sdom[v.Index] = v + lt.link(nil, v) + for _, w := range v.Succs { + if lt.sdom[w.Index] == nil { + lt.parent[w.Index] = v + i = lt.dfs(w, i, preorder) + } + } + return i +} + +// eval implements the EVAL part of the LT algorithm. +func (lt *ltState) eval(v *BasicBlock) *BasicBlock { + // TODO(adonovan): opt: do path compression per simple LT. + u := v + for ; lt.ancestor[v.Index] != nil; v = lt.ancestor[v.Index] { + if lt.sdom[v.Index].dom.pre < lt.sdom[u.Index].dom.pre { + u = v + } + } + return u +} + +// link implements the LINK part of the LT algorithm. +func (lt *ltState) link(v, w *BasicBlock) { + lt.ancestor[w.Index] = v +} + +// buildDomTree computes the dominator tree of f using the LT algorithm. +// Precondition: all blocks are reachable (e.g. optimizeBlocks has been run). +// +func buildDomTree(f *Function) { + // The step numbers refer to the original LT paper; the + // reordering is due to Georgiadis. + + // Clear any previous domInfo. + for _, b := range f.Blocks { + b.dom = domInfo{} + } + + n := len(f.Blocks) + // Allocate space for 5 contiguous [n]*BasicBlock arrays: + // sdom, parent, ancestor, preorder, buckets. + space := make([]*BasicBlock, 5*n, 5*n) + lt := ltState{ + sdom: space[0:n], + parent: space[n : 2*n], + ancestor: space[2*n : 3*n], + } + + // Step 1. Number vertices by depth-first preorder. + preorder := space[3*n : 4*n] + root := f.Blocks[0] + prenum := lt.dfs(root, 0, preorder) + recover := f.Recover + if recover != nil { + lt.dfs(recover, prenum, preorder) + } + + buckets := space[4*n : 5*n] + copy(buckets, preorder) + + // In reverse preorder... + for i := int32(n) - 1; i > 0; i-- { + w := preorder[i] + + // Step 3. Implicitly define the immediate dominator of each node. + for v := buckets[i]; v != w; v = buckets[v.dom.pre] { + u := lt.eval(v) + if lt.sdom[u.Index].dom.pre < i { + v.dom.idom = u + } else { + v.dom.idom = w + } + } + + // Step 2. Compute the semidominators of all nodes. + lt.sdom[w.Index] = lt.parent[w.Index] + for _, v := range w.Preds { + u := lt.eval(v) + if lt.sdom[u.Index].dom.pre < lt.sdom[w.Index].dom.pre { + lt.sdom[w.Index] = lt.sdom[u.Index] + } + } + + lt.link(lt.parent[w.Index], w) + + if lt.parent[w.Index] == lt.sdom[w.Index] { + w.dom.idom = lt.parent[w.Index] + } else { + buckets[i] = buckets[lt.sdom[w.Index].dom.pre] + buckets[lt.sdom[w.Index].dom.pre] = w + } + } + + // The final 'Step 3' is now outside the loop. + for v := buckets[0]; v != root; v = buckets[v.dom.pre] { + v.dom.idom = root + } + + // Step 4. Explicitly define the immediate dominator of each + // node, in preorder. + for _, w := range preorder[1:] { + if w == root || w == recover { + w.dom.idom = nil + } else { + if w.dom.idom != lt.sdom[w.Index] { + w.dom.idom = w.dom.idom.dom.idom + } + // Calculate Children relation as inverse of Idom. + w.dom.idom.dom.children = append(w.dom.idom.dom.children, w) + } + } + + pre, post := numberDomTree(root, 0, 0) + if recover != nil { + numberDomTree(recover, pre, post) + } + + // printDomTreeDot(os.Stderr, f) // debugging + // printDomTreeText(os.Stderr, root, 0) // debugging + + if f.Prog.mode&SanityCheckFunctions != 0 { + sanityCheckDomTree(f) + } +} + +// numberDomTree sets the pre- and post-order numbers of a depth-first +// traversal of the dominator tree rooted at v. These are used to +// answer dominance queries in constant time. +// +func numberDomTree(v *BasicBlock, pre, post int32) (int32, int32) { + v.dom.pre = pre + pre++ + for _, child := range v.dom.children { + pre, post = numberDomTree(child, pre, post) + } + v.dom.post = post + post++ + return pre, post +} + +// Testing utilities ---------------------------------------- + +// sanityCheckDomTree checks the correctness of the dominator tree +// computed by the LT algorithm by comparing against the dominance +// relation computed by a naive Kildall-style forward dataflow +// analysis (Algorithm 10.16 from the "Dragon" book). +// +func sanityCheckDomTree(f *Function) { + n := len(f.Blocks) + + // D[i] is the set of blocks that dominate f.Blocks[i], + // represented as a bit-set of block indices. + D := make([]big.Int, n) + + one := big.NewInt(1) + + // all is the set of all blocks; constant. + var all big.Int + all.Set(one).Lsh(&all, uint(n)).Sub(&all, one) + + // Initialization. + for i, b := range f.Blocks { + if i == 0 || b == f.Recover { + // A root is dominated only by itself. + D[i].SetBit(&D[0], 0, 1) + } else { + // All other blocks are (initially) dominated + // by every block. + D[i].Set(&all) + } + } + + // Iteration until fixed point. + for changed := true; changed; { + changed = false + for i, b := range f.Blocks { + if i == 0 || b == f.Recover { + continue + } + // Compute intersection across predecessors. + var x big.Int + x.Set(&all) + for _, pred := range b.Preds { + x.And(&x, &D[pred.Index]) + } + x.SetBit(&x, i, 1) // a block always dominates itself. + if D[i].Cmp(&x) != 0 { + D[i].Set(&x) + changed = true + } + } + } + + // Check the entire relation. O(n^2). + // The Recover block (if any) must be treated specially so we skip it. + ok := true + for i := 0; i < n; i++ { + for j := 0; j < n; j++ { + b, c := f.Blocks[i], f.Blocks[j] + if c == f.Recover { + continue + } + actual := b.Dominates(c) + expected := D[j].Bit(i) == 1 + if actual != expected { + fmt.Fprintf(os.Stderr, "dominates(%s, %s)==%t, want %t\n", b, c, actual, expected) + ok = false + } + } + } + + preorder := f.DomPreorder() + for _, b := range f.Blocks { + if got := preorder[b.dom.pre]; got != b { + fmt.Fprintf(os.Stderr, "preorder[%d]==%s, want %s\n", b.dom.pre, got, b) + ok = false + } + } + + if !ok { + panic("sanityCheckDomTree failed for " + f.String()) + } + +} + +// Printing functions ---------------------------------------- + +// printDomTree prints the dominator tree as text, using indentation. +func printDomTreeText(buf *bytes.Buffer, v *BasicBlock, indent int) { + fmt.Fprintf(buf, "%*s%s\n", 4*indent, "", v) + for _, child := range v.dom.children { + printDomTreeText(buf, child, indent+1) + } +} + +// printDomTreeDot prints the dominator tree of f in AT&T GraphViz +// (.dot) format. +func printDomTreeDot(buf *bytes.Buffer, f *Function) { + fmt.Fprintln(buf, "//", f) + fmt.Fprintln(buf, "digraph domtree {") + for i, b := range f.Blocks { + v := b.dom + fmt.Fprintf(buf, "\tn%d [label=\"%s (%d, %d)\",shape=\"rectangle\"];\n", v.pre, b, v.pre, v.post) + // TODO(adonovan): improve appearance of edges + // belonging to both dominator tree and CFG. + + // Dominator tree edge. + if i != 0 { + fmt.Fprintf(buf, "\tn%d -> n%d [style=\"solid\",weight=100];\n", v.idom.dom.pre, v.pre) + } + // CFG edges. + for _, pred := range b.Preds { + fmt.Fprintf(buf, "\tn%d -> n%d [style=\"dotted\",weight=0];\n", pred.dom.pre, v.pre) + } + } + fmt.Fprintln(buf, "}") +} diff --git a/vendor/honnef.co/go/tools/ssa/emit.go b/vendor/honnef.co/go/tools/ssa/emit.go new file mode 100644 index 0000000000..1036988adc --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/emit.go @@ -0,0 +1,468 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// Helpers for emitting SSA instructions. + +import ( + "fmt" + "go/ast" + "go/token" + "go/types" +) + +// emitNew emits to f a new (heap Alloc) instruction allocating an +// object of type typ. pos is the optional source location. +// +func emitNew(f *Function, typ types.Type, pos token.Pos) *Alloc { + v := &Alloc{Heap: true} + v.setType(types.NewPointer(typ)) + v.setPos(pos) + f.emit(v) + return v +} + +// emitLoad emits to f an instruction to load the address addr into a +// new temporary, and returns the value so defined. +// +func emitLoad(f *Function, addr Value) *UnOp { + v := &UnOp{Op: token.MUL, X: addr} + v.setType(deref(addr.Type())) + f.emit(v) + return v +} + +// emitDebugRef emits to f a DebugRef pseudo-instruction associating +// expression e with value v. +// +func emitDebugRef(f *Function, e ast.Expr, v Value, isAddr bool) { + if !f.debugInfo() { + return // debugging not enabled + } + if v == nil || e == nil { + panic("nil") + } + var obj types.Object + e = unparen(e) + if id, ok := e.(*ast.Ident); ok { + if isBlankIdent(id) { + return + } + obj = f.Pkg.objectOf(id) + switch obj.(type) { + case *types.Nil, *types.Const, *types.Builtin: + return + } + } + f.emit(&DebugRef{ + X: v, + Expr: e, + IsAddr: isAddr, + object: obj, + }) +} + +// emitArith emits to f code to compute the binary operation op(x, y) +// where op is an eager shift, logical or arithmetic operation. +// (Use emitCompare() for comparisons and Builder.logicalBinop() for +// non-eager operations.) +// +func emitArith(f *Function, op token.Token, x, y Value, t types.Type, pos token.Pos) Value { + switch op { + case token.SHL, token.SHR: + x = emitConv(f, x, t) + // y may be signed or an 'untyped' constant. + // TODO(adonovan): whence signed values? + if b, ok := y.Type().Underlying().(*types.Basic); ok && b.Info()&types.IsUnsigned == 0 { + y = emitConv(f, y, types.Typ[types.Uint64]) + } + + case token.ADD, token.SUB, token.MUL, token.QUO, token.REM, token.AND, token.OR, token.XOR, token.AND_NOT: + x = emitConv(f, x, t) + y = emitConv(f, y, t) + + default: + panic("illegal op in emitArith: " + op.String()) + + } + v := &BinOp{ + Op: op, + X: x, + Y: y, + } + v.setPos(pos) + v.setType(t) + return f.emit(v) +} + +// emitCompare emits to f code compute the boolean result of +// comparison comparison 'x op y'. +// +func emitCompare(f *Function, op token.Token, x, y Value, pos token.Pos) Value { + xt := x.Type().Underlying() + yt := y.Type().Underlying() + + // Special case to optimise a tagless SwitchStmt so that + // these are equivalent + // switch { case e: ...} + // switch true { case e: ... } + // if e==true { ... } + // even in the case when e's type is an interface. + // TODO(adonovan): opt: generalise to x==true, false!=y, etc. + if x == vTrue && op == token.EQL { + if yt, ok := yt.(*types.Basic); ok && yt.Info()&types.IsBoolean != 0 { + return y + } + } + + if types.Identical(xt, yt) { + // no conversion necessary + } else if _, ok := xt.(*types.Interface); ok { + y = emitConv(f, y, x.Type()) + } else if _, ok := yt.(*types.Interface); ok { + x = emitConv(f, x, y.Type()) + } else if _, ok := x.(*Const); ok { + x = emitConv(f, x, y.Type()) + } else if _, ok := y.(*Const); ok { + y = emitConv(f, y, x.Type()) + } else { + // other cases, e.g. channels. No-op. + } + + v := &BinOp{ + Op: op, + X: x, + Y: y, + } + v.setPos(pos) + v.setType(tBool) + return f.emit(v) +} + +// isValuePreserving returns true if a conversion from ut_src to +// ut_dst is value-preserving, i.e. just a change of type. +// Precondition: neither argument is a named type. +// +func isValuePreserving(ut_src, ut_dst types.Type) bool { + // Identical underlying types? + if structTypesIdentical(ut_dst, ut_src) { + return true + } + + switch ut_dst.(type) { + case *types.Chan: + // Conversion between channel types? + _, ok := ut_src.(*types.Chan) + return ok + + case *types.Pointer: + // Conversion between pointers with identical base types? + _, ok := ut_src.(*types.Pointer) + return ok + } + return false +} + +// emitConv emits to f code to convert Value val to exactly type typ, +// and returns the converted value. Implicit conversions are required +// by language assignability rules in assignments, parameter passing, +// etc. Conversions cannot fail dynamically. +// +func emitConv(f *Function, val Value, typ types.Type) Value { + t_src := val.Type() + + // Identical types? Conversion is a no-op. + if types.Identical(t_src, typ) { + return val + } + + ut_dst := typ.Underlying() + ut_src := t_src.Underlying() + + // Just a change of type, but not value or representation? + if isValuePreserving(ut_src, ut_dst) { + c := &ChangeType{X: val} + c.setType(typ) + return f.emit(c) + } + + // Conversion to, or construction of a value of, an interface type? + if _, ok := ut_dst.(*types.Interface); ok { + // Assignment from one interface type to another? + if _, ok := ut_src.(*types.Interface); ok { + c := &ChangeInterface{X: val} + c.setType(typ) + return f.emit(c) + } + + // Untyped nil constant? Return interface-typed nil constant. + if ut_src == tUntypedNil { + return nilConst(typ) + } + + // Convert (non-nil) "untyped" literals to their default type. + if t, ok := ut_src.(*types.Basic); ok && t.Info()&types.IsUntyped != 0 { + val = emitConv(f, val, DefaultType(ut_src)) + } + + f.Pkg.Prog.needMethodsOf(val.Type()) + mi := &MakeInterface{X: val} + mi.setType(typ) + return f.emit(mi) + } + + // Conversion of a compile-time constant value? + if c, ok := val.(*Const); ok { + if _, ok := ut_dst.(*types.Basic); ok || c.IsNil() { + // Conversion of a compile-time constant to + // another constant type results in a new + // constant of the destination type and + // (initially) the same abstract value. + // We don't truncate the value yet. + return NewConst(c.Value, typ) + } + + // We're converting from constant to non-constant type, + // e.g. string -> []byte/[]rune. + } + + // A representation-changing conversion? + // At least one of {ut_src,ut_dst} must be *Basic. + // (The other may be []byte or []rune.) + _, ok1 := ut_src.(*types.Basic) + _, ok2 := ut_dst.(*types.Basic) + if ok1 || ok2 { + c := &Convert{X: val} + c.setType(typ) + return f.emit(c) + } + + panic(fmt.Sprintf("in %s: cannot convert %s (%s) to %s", f, val, val.Type(), typ)) +} + +// emitStore emits to f an instruction to store value val at location +// addr, applying implicit conversions as required by assignability rules. +// +func emitStore(f *Function, addr, val Value, pos token.Pos) *Store { + s := &Store{ + Addr: addr, + Val: emitConv(f, val, deref(addr.Type())), + pos: pos, + } + f.emit(s) + return s +} + +// emitJump emits to f a jump to target, and updates the control-flow graph. +// Postcondition: f.currentBlock is nil. +// +func emitJump(f *Function, target *BasicBlock) { + b := f.currentBlock + b.emit(new(Jump)) + addEdge(b, target) + f.currentBlock = nil +} + +// emitIf emits to f a conditional jump to tblock or fblock based on +// cond, and updates the control-flow graph. +// Postcondition: f.currentBlock is nil. +// +func emitIf(f *Function, cond Value, tblock, fblock *BasicBlock) { + b := f.currentBlock + b.emit(&If{Cond: cond}) + addEdge(b, tblock) + addEdge(b, fblock) + f.currentBlock = nil +} + +// emitExtract emits to f an instruction to extract the index'th +// component of tuple. It returns the extracted value. +// +func emitExtract(f *Function, tuple Value, index int) Value { + e := &Extract{Tuple: tuple, Index: index} + e.setType(tuple.Type().(*types.Tuple).At(index).Type()) + return f.emit(e) +} + +// emitTypeAssert emits to f a type assertion value := x.(t) and +// returns the value. x.Type() must be an interface. +// +func emitTypeAssert(f *Function, x Value, t types.Type, pos token.Pos) Value { + a := &TypeAssert{X: x, AssertedType: t} + a.setPos(pos) + a.setType(t) + return f.emit(a) +} + +// emitTypeTest emits to f a type test value,ok := x.(t) and returns +// a (value, ok) tuple. x.Type() must be an interface. +// +func emitTypeTest(f *Function, x Value, t types.Type, pos token.Pos) Value { + a := &TypeAssert{ + X: x, + AssertedType: t, + CommaOk: true, + } + a.setPos(pos) + a.setType(types.NewTuple( + newVar("value", t), + varOk, + )) + return f.emit(a) +} + +// emitTailCall emits to f a function call in tail position. The +// caller is responsible for all fields of 'call' except its type. +// Intended for wrapper methods. +// Precondition: f does/will not use deferred procedure calls. +// Postcondition: f.currentBlock is nil. +// +func emitTailCall(f *Function, call *Call) { + tresults := f.Signature.Results() + nr := tresults.Len() + if nr == 1 { + call.typ = tresults.At(0).Type() + } else { + call.typ = tresults + } + tuple := f.emit(call) + var ret Return + switch nr { + case 0: + // no-op + case 1: + ret.Results = []Value{tuple} + default: + for i := 0; i < nr; i++ { + v := emitExtract(f, tuple, i) + // TODO(adonovan): in principle, this is required: + // v = emitConv(f, o.Type, f.Signature.Results[i].Type) + // but in practice emitTailCall is only used when + // the types exactly match. + ret.Results = append(ret.Results, v) + } + } + f.emit(&ret) + f.currentBlock = nil +} + +// emitImplicitSelections emits to f code to apply the sequence of +// implicit field selections specified by indices to base value v, and +// returns the selected value. +// +// If v is the address of a struct, the result will be the address of +// a field; if it is the value of a struct, the result will be the +// value of a field. +// +func emitImplicitSelections(f *Function, v Value, indices []int) Value { + for _, index := range indices { + fld := deref(v.Type()).Underlying().(*types.Struct).Field(index) + + if isPointer(v.Type()) { + instr := &FieldAddr{ + X: v, + Field: index, + } + instr.setType(types.NewPointer(fld.Type())) + v = f.emit(instr) + // Load the field's value iff indirectly embedded. + if isPointer(fld.Type()) { + v = emitLoad(f, v) + } + } else { + instr := &Field{ + X: v, + Field: index, + } + instr.setType(fld.Type()) + v = f.emit(instr) + } + } + return v +} + +// emitFieldSelection emits to f code to select the index'th field of v. +// +// If wantAddr, the input must be a pointer-to-struct and the result +// will be the field's address; otherwise the result will be the +// field's value. +// Ident id is used for position and debug info. +// +func emitFieldSelection(f *Function, v Value, index int, wantAddr bool, id *ast.Ident) Value { + fld := deref(v.Type()).Underlying().(*types.Struct).Field(index) + if isPointer(v.Type()) { + instr := &FieldAddr{ + X: v, + Field: index, + } + instr.setPos(id.Pos()) + instr.setType(types.NewPointer(fld.Type())) + v = f.emit(instr) + // Load the field's value iff we don't want its address. + if !wantAddr { + v = emitLoad(f, v) + } + } else { + instr := &Field{ + X: v, + Field: index, + } + instr.setPos(id.Pos()) + instr.setType(fld.Type()) + v = f.emit(instr) + } + emitDebugRef(f, id, v, wantAddr) + return v +} + +// zeroValue emits to f code to produce a zero value of type t, +// and returns it. +// +func zeroValue(f *Function, t types.Type) Value { + switch t.Underlying().(type) { + case *types.Struct, *types.Array: + return emitLoad(f, f.addLocal(t, token.NoPos)) + default: + return zeroConst(t) + } +} + +// createRecoverBlock emits to f a block of code to return after a +// recovered panic, and sets f.Recover to it. +// +// If f's result parameters are named, the code loads and returns +// their current values, otherwise it returns the zero values of their +// type. +// +// Idempotent. +// +func createRecoverBlock(f *Function) { + if f.Recover != nil { + return // already created + } + saved := f.currentBlock + + f.Recover = f.newBasicBlock("recover") + f.currentBlock = f.Recover + + var results []Value + if f.namedResults != nil { + // Reload NRPs to form value tuple. + for _, r := range f.namedResults { + results = append(results, emitLoad(f, r)) + } + } else { + R := f.Signature.Results() + for i, n := 0, R.Len(); i < n; i++ { + T := R.At(i).Type() + + // Return zero value of each result type. + results = append(results, zeroValue(f, T)) + } + } + f.emit(&Return{Results: results}) + + f.currentBlock = saved +} diff --git a/vendor/honnef.co/go/tools/ssa/func.go b/vendor/honnef.co/go/tools/ssa/func.go new file mode 100644 index 0000000000..53635ba011 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/func.go @@ -0,0 +1,701 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file implements the Function and BasicBlock types. + +import ( + "bytes" + "fmt" + "go/ast" + "go/token" + "go/types" + "io" + "os" + "strings" +) + +// addEdge adds a control-flow graph edge from from to to. +func addEdge(from, to *BasicBlock) { + from.Succs = append(from.Succs, to) + to.Preds = append(to.Preds, from) +} + +// Parent returns the function that contains block b. +func (b *BasicBlock) Parent() *Function { return b.parent } + +// String returns a human-readable label of this block. +// It is not guaranteed unique within the function. +// +func (b *BasicBlock) String() string { + return fmt.Sprintf("%d", b.Index) +} + +// emit appends an instruction to the current basic block. +// If the instruction defines a Value, it is returned. +// +func (b *BasicBlock) emit(i Instruction) Value { + i.setBlock(b) + b.Instrs = append(b.Instrs, i) + v, _ := i.(Value) + return v +} + +// predIndex returns the i such that b.Preds[i] == c or panics if +// there is none. +func (b *BasicBlock) predIndex(c *BasicBlock) int { + for i, pred := range b.Preds { + if pred == c { + return i + } + } + panic(fmt.Sprintf("no edge %s -> %s", c, b)) +} + +// hasPhi returns true if b.Instrs contains φ-nodes. +func (b *BasicBlock) hasPhi() bool { + _, ok := b.Instrs[0].(*Phi) + return ok +} + +func (b *BasicBlock) Phis() []Instruction { + return b.phis() +} + +// phis returns the prefix of b.Instrs containing all the block's φ-nodes. +func (b *BasicBlock) phis() []Instruction { + for i, instr := range b.Instrs { + if _, ok := instr.(*Phi); !ok { + return b.Instrs[:i] + } + } + return nil // unreachable in well-formed blocks +} + +// replacePred replaces all occurrences of p in b's predecessor list with q. +// Ordinarily there should be at most one. +// +func (b *BasicBlock) replacePred(p, q *BasicBlock) { + for i, pred := range b.Preds { + if pred == p { + b.Preds[i] = q + } + } +} + +// replaceSucc replaces all occurrences of p in b's successor list with q. +// Ordinarily there should be at most one. +// +func (b *BasicBlock) replaceSucc(p, q *BasicBlock) { + for i, succ := range b.Succs { + if succ == p { + b.Succs[i] = q + } + } +} + +func (b *BasicBlock) RemovePred(p *BasicBlock) { + b.removePred(p) +} + +// removePred removes all occurrences of p in b's +// predecessor list and φ-nodes. +// Ordinarily there should be at most one. +// +func (b *BasicBlock) removePred(p *BasicBlock) { + phis := b.phis() + + // We must preserve edge order for φ-nodes. + j := 0 + for i, pred := range b.Preds { + if pred != p { + b.Preds[j] = b.Preds[i] + // Strike out φ-edge too. + for _, instr := range phis { + phi := instr.(*Phi) + phi.Edges[j] = phi.Edges[i] + } + j++ + } + } + // Nil out b.Preds[j:] and φ-edges[j:] to aid GC. + for i := j; i < len(b.Preds); i++ { + b.Preds[i] = nil + for _, instr := range phis { + instr.(*Phi).Edges[i] = nil + } + } + b.Preds = b.Preds[:j] + for _, instr := range phis { + phi := instr.(*Phi) + phi.Edges = phi.Edges[:j] + } +} + +// Destinations associated with unlabelled for/switch/select stmts. +// We push/pop one of these as we enter/leave each construct and for +// each BranchStmt we scan for the innermost target of the right type. +// +type targets struct { + tail *targets // rest of stack + _break *BasicBlock + _continue *BasicBlock + _fallthrough *BasicBlock +} + +// Destinations associated with a labelled block. +// We populate these as labels are encountered in forward gotos or +// labelled statements. +// +type lblock struct { + _goto *BasicBlock + _break *BasicBlock + _continue *BasicBlock +} + +// labelledBlock returns the branch target associated with the +// specified label, creating it if needed. +// +func (f *Function) labelledBlock(label *ast.Ident) *lblock { + lb := f.lblocks[label.Obj] + if lb == nil { + lb = &lblock{_goto: f.newBasicBlock(label.Name)} + if f.lblocks == nil { + f.lblocks = make(map[*ast.Object]*lblock) + } + f.lblocks[label.Obj] = lb + } + return lb +} + +// addParam adds a (non-escaping) parameter to f.Params of the +// specified name, type and source position. +// +func (f *Function) addParam(name string, typ types.Type, pos token.Pos) *Parameter { + v := &Parameter{ + name: name, + typ: typ, + pos: pos, + parent: f, + } + f.Params = append(f.Params, v) + return v +} + +func (f *Function) addParamObj(obj types.Object) *Parameter { + name := obj.Name() + if name == "" { + name = fmt.Sprintf("arg%d", len(f.Params)) + } + param := f.addParam(name, obj.Type(), obj.Pos()) + param.object = obj + return param +} + +// addSpilledParam declares a parameter that is pre-spilled to the +// stack; the function body will load/store the spilled location. +// Subsequent lifting will eliminate spills where possible. +// +func (f *Function) addSpilledParam(obj types.Object) { + param := f.addParamObj(obj) + spill := &Alloc{Comment: obj.Name()} + spill.setType(types.NewPointer(obj.Type())) + spill.setPos(obj.Pos()) + f.objects[obj] = spill + f.Locals = append(f.Locals, spill) + f.emit(spill) + f.emit(&Store{Addr: spill, Val: param}) +} + +// startBody initializes the function prior to generating SSA code for its body. +// Precondition: f.Type() already set. +// +func (f *Function) startBody() { + f.currentBlock = f.newBasicBlock("entry") + f.objects = make(map[types.Object]Value) // needed for some synthetics, e.g. init +} + +// createSyntacticParams populates f.Params and generates code (spills +// and named result locals) for all the parameters declared in the +// syntax. In addition it populates the f.objects mapping. +// +// Preconditions: +// f.startBody() was called. +// Postcondition: +// len(f.Params) == len(f.Signature.Params) + (f.Signature.Recv() ? 1 : 0) +// +func (f *Function) createSyntacticParams(recv *ast.FieldList, functype *ast.FuncType) { + // Receiver (at most one inner iteration). + if recv != nil { + for _, field := range recv.List { + for _, n := range field.Names { + f.addSpilledParam(f.Pkg.info.Defs[n]) + } + // Anonymous receiver? No need to spill. + if field.Names == nil { + f.addParamObj(f.Signature.Recv()) + } + } + } + + // Parameters. + if functype.Params != nil { + n := len(f.Params) // 1 if has recv, 0 otherwise + for _, field := range functype.Params.List { + for _, n := range field.Names { + f.addSpilledParam(f.Pkg.info.Defs[n]) + } + // Anonymous parameter? No need to spill. + if field.Names == nil { + f.addParamObj(f.Signature.Params().At(len(f.Params) - n)) + } + } + } + + // Named results. + if functype.Results != nil { + for _, field := range functype.Results.List { + // Implicit "var" decl of locals for named results. + for _, n := range field.Names { + f.namedResults = append(f.namedResults, f.addLocalForIdent(n)) + } + } + } +} + +// numberRegisters assigns numbers to all SSA registers +// (value-defining Instructions) in f, to aid debugging. +// (Non-Instruction Values are named at construction.) +// +func numberRegisters(f *Function) { + v := 0 + for _, b := range f.Blocks { + for _, instr := range b.Instrs { + switch instr.(type) { + case Value: + instr.(interface { + setNum(int) + }).setNum(v) + v++ + } + } + } +} + +// buildReferrers populates the def/use information in all non-nil +// Value.Referrers slice. +// Precondition: all such slices are initially empty. +func buildReferrers(f *Function) { + var rands []*Value + for _, b := range f.Blocks { + for _, instr := range b.Instrs { + rands = instr.Operands(rands[:0]) // recycle storage + for _, rand := range rands { + if r := *rand; r != nil { + if ref := r.Referrers(); ref != nil { + *ref = append(*ref, instr) + } + } + } + } + } +} + +// finishBody() finalizes the function after SSA code generation of its body. +func (f *Function) finishBody() { + f.objects = nil + f.currentBlock = nil + f.lblocks = nil + + // Don't pin the AST in memory (except in debug mode). + if n := f.syntax; n != nil && !f.debugInfo() { + f.syntax = extentNode{n.Pos(), n.End()} + } + + // Remove from f.Locals any Allocs that escape to the heap. + j := 0 + for _, l := range f.Locals { + if !l.Heap { + f.Locals[j] = l + j++ + } + } + // Nil out f.Locals[j:] to aid GC. + for i := j; i < len(f.Locals); i++ { + f.Locals[i] = nil + } + f.Locals = f.Locals[:j] + + optimizeBlocks(f) + + buildReferrers(f) + + buildDomTree(f) + + if f.Prog.mode&NaiveForm == 0 { + // For debugging pre-state of lifting pass: + // numberRegisters(f) + // f.WriteTo(os.Stderr) + lift(f) + } + + f.namedResults = nil // (used by lifting) + + numberRegisters(f) + + if f.Prog.mode&PrintFunctions != 0 { + printMu.Lock() + f.WriteTo(os.Stdout) + printMu.Unlock() + } + + if f.Prog.mode&SanityCheckFunctions != 0 { + mustSanityCheck(f, nil) + } +} + +func (f *Function) RemoveNilBlocks() { + f.removeNilBlocks() +} + +// removeNilBlocks eliminates nils from f.Blocks and updates each +// BasicBlock.Index. Use this after any pass that may delete blocks. +// +func (f *Function) removeNilBlocks() { + j := 0 + for _, b := range f.Blocks { + if b != nil { + b.Index = j + f.Blocks[j] = b + j++ + } + } + // Nil out f.Blocks[j:] to aid GC. + for i := j; i < len(f.Blocks); i++ { + f.Blocks[i] = nil + } + f.Blocks = f.Blocks[:j] +} + +// SetDebugMode sets the debug mode for package pkg. If true, all its +// functions will include full debug info. This greatly increases the +// size of the instruction stream, and causes Functions to depend upon +// the ASTs, potentially keeping them live in memory for longer. +// +func (pkg *Package) SetDebugMode(debug bool) { + // TODO(adonovan): do we want ast.File granularity? + pkg.debug = debug +} + +// debugInfo reports whether debug info is wanted for this function. +func (f *Function) debugInfo() bool { + return f.Pkg != nil && f.Pkg.debug +} + +// addNamedLocal creates a local variable, adds it to function f and +// returns it. Its name and type are taken from obj. Subsequent +// calls to f.lookup(obj) will return the same local. +// +func (f *Function) addNamedLocal(obj types.Object) *Alloc { + l := f.addLocal(obj.Type(), obj.Pos()) + l.Comment = obj.Name() + f.objects[obj] = l + return l +} + +func (f *Function) addLocalForIdent(id *ast.Ident) *Alloc { + return f.addNamedLocal(f.Pkg.info.Defs[id]) +} + +// addLocal creates an anonymous local variable of type typ, adds it +// to function f and returns it. pos is the optional source location. +// +func (f *Function) addLocal(typ types.Type, pos token.Pos) *Alloc { + v := &Alloc{} + v.setType(types.NewPointer(typ)) + v.setPos(pos) + f.Locals = append(f.Locals, v) + f.emit(v) + return v +} + +// lookup returns the address of the named variable identified by obj +// that is local to function f or one of its enclosing functions. +// If escaping, the reference comes from a potentially escaping pointer +// expression and the referent must be heap-allocated. +// +func (f *Function) lookup(obj types.Object, escaping bool) Value { + if v, ok := f.objects[obj]; ok { + if alloc, ok := v.(*Alloc); ok && escaping { + alloc.Heap = true + } + return v // function-local var (address) + } + + // Definition must be in an enclosing function; + // plumb it through intervening closures. + if f.parent == nil { + panic("no ssa.Value for " + obj.String()) + } + outer := f.parent.lookup(obj, true) // escaping + v := &FreeVar{ + name: obj.Name(), + typ: outer.Type(), + pos: outer.Pos(), + outer: outer, + parent: f, + } + f.objects[obj] = v + f.FreeVars = append(f.FreeVars, v) + return v +} + +// emit emits the specified instruction to function f. +func (f *Function) emit(instr Instruction) Value { + return f.currentBlock.emit(instr) +} + +// RelString returns the full name of this function, qualified by +// package name, receiver type, etc. +// +// The specific formatting rules are not guaranteed and may change. +// +// Examples: +// "math.IsNaN" // a package-level function +// "(*bytes.Buffer).Bytes" // a declared method or a wrapper +// "(*bytes.Buffer).Bytes$thunk" // thunk (func wrapping method; receiver is param 0) +// "(*bytes.Buffer).Bytes$bound" // bound (func wrapping method; receiver supplied by closure) +// "main.main$1" // an anonymous function in main +// "main.init#1" // a declared init function +// "main.init" // the synthesized package initializer +// +// When these functions are referred to from within the same package +// (i.e. from == f.Pkg.Object), they are rendered without the package path. +// For example: "IsNaN", "(*Buffer).Bytes", etc. +// +// All non-synthetic functions have distinct package-qualified names. +// (But two methods may have the same name "(T).f" if one is a synthetic +// wrapper promoting a non-exported method "f" from another package; in +// that case, the strings are equal but the identifiers "f" are distinct.) +// +func (f *Function) RelString(from *types.Package) string { + // Anonymous? + if f.parent != nil { + // An anonymous function's Name() looks like "parentName$1", + // but its String() should include the type/package/etc. + parent := f.parent.RelString(from) + for i, anon := range f.parent.AnonFuncs { + if anon == f { + return fmt.Sprintf("%s$%d", parent, 1+i) + } + } + + return f.name // should never happen + } + + // Method (declared or wrapper)? + if recv := f.Signature.Recv(); recv != nil { + return f.relMethod(from, recv.Type()) + } + + // Thunk? + if f.method != nil { + return f.relMethod(from, f.method.Recv()) + } + + // Bound? + if len(f.FreeVars) == 1 && strings.HasSuffix(f.name, "$bound") { + return f.relMethod(from, f.FreeVars[0].Type()) + } + + // Package-level function? + // Prefix with package name for cross-package references only. + if p := f.pkg(); p != nil && p != from { + return fmt.Sprintf("%s.%s", p.Path(), f.name) + } + + // Unknown. + return f.name +} + +func (f *Function) relMethod(from *types.Package, recv types.Type) string { + return fmt.Sprintf("(%s).%s", relType(recv, from), f.name) +} + +// writeSignature writes to buf the signature sig in declaration syntax. +func writeSignature(buf *bytes.Buffer, from *types.Package, name string, sig *types.Signature, params []*Parameter) { + buf.WriteString("func ") + if recv := sig.Recv(); recv != nil { + buf.WriteString("(") + if n := params[0].Name(); n != "" { + buf.WriteString(n) + buf.WriteString(" ") + } + types.WriteType(buf, params[0].Type(), types.RelativeTo(from)) + buf.WriteString(") ") + } + buf.WriteString(name) + types.WriteSignature(buf, sig, types.RelativeTo(from)) +} + +func (f *Function) pkg() *types.Package { + if f.Pkg != nil { + return f.Pkg.Pkg + } + return nil +} + +var _ io.WriterTo = (*Function)(nil) // *Function implements io.Writer + +func (f *Function) WriteTo(w io.Writer) (int64, error) { + var buf bytes.Buffer + WriteFunction(&buf, f) + n, err := w.Write(buf.Bytes()) + return int64(n), err +} + +// WriteFunction writes to buf a human-readable "disassembly" of f. +func WriteFunction(buf *bytes.Buffer, f *Function) { + fmt.Fprintf(buf, "# Name: %s\n", f.String()) + if f.Pkg != nil { + fmt.Fprintf(buf, "# Package: %s\n", f.Pkg.Pkg.Path()) + } + if syn := f.Synthetic; syn != "" { + fmt.Fprintln(buf, "# Synthetic:", syn) + } + if pos := f.Pos(); pos.IsValid() { + fmt.Fprintf(buf, "# Location: %s\n", f.Prog.Fset.Position(pos)) + } + + if f.parent != nil { + fmt.Fprintf(buf, "# Parent: %s\n", f.parent.Name()) + } + + if f.Recover != nil { + fmt.Fprintf(buf, "# Recover: %s\n", f.Recover) + } + + from := f.pkg() + + if f.FreeVars != nil { + buf.WriteString("# Free variables:\n") + for i, fv := range f.FreeVars { + fmt.Fprintf(buf, "# % 3d:\t%s %s\n", i, fv.Name(), relType(fv.Type(), from)) + } + } + + if len(f.Locals) > 0 { + buf.WriteString("# Locals:\n") + for i, l := range f.Locals { + fmt.Fprintf(buf, "# % 3d:\t%s %s\n", i, l.Name(), relType(deref(l.Type()), from)) + } + } + writeSignature(buf, from, f.Name(), f.Signature, f.Params) + buf.WriteString(":\n") + + if f.Blocks == nil { + buf.WriteString("\t(external)\n") + } + + // NB. column calculations are confused by non-ASCII + // characters and assume 8-space tabs. + const punchcard = 80 // for old time's sake. + const tabwidth = 8 + for _, b := range f.Blocks { + if b == nil { + // Corrupt CFG. + fmt.Fprintf(buf, ".nil:\n") + continue + } + n, _ := fmt.Fprintf(buf, "%d:", b.Index) + bmsg := fmt.Sprintf("%s P:%d S:%d", b.Comment, len(b.Preds), len(b.Succs)) + fmt.Fprintf(buf, "%*s%s\n", punchcard-1-n-len(bmsg), "", bmsg) + + if false { // CFG debugging + fmt.Fprintf(buf, "\t# CFG: %s --> %s --> %s\n", b.Preds, b, b.Succs) + } + for _, instr := range b.Instrs { + buf.WriteString("\t") + switch v := instr.(type) { + case Value: + l := punchcard - tabwidth + // Left-align the instruction. + if name := v.Name(); name != "" { + n, _ := fmt.Fprintf(buf, "%s = ", name) + l -= n + } + n, _ := buf.WriteString(instr.String()) + l -= n + // Right-align the type if there's space. + if t := v.Type(); t != nil { + buf.WriteByte(' ') + ts := relType(t, from) + l -= len(ts) + len(" ") // (spaces before and after type) + if l > 0 { + fmt.Fprintf(buf, "%*s", l, "") + } + buf.WriteString(ts) + } + case nil: + // Be robust against bad transforms. + buf.WriteString("") + default: + buf.WriteString(instr.String()) + } + buf.WriteString("\n") + } + } + fmt.Fprintf(buf, "\n") +} + +// newBasicBlock adds to f a new basic block and returns it. It does +// not automatically become the current block for subsequent calls to emit. +// comment is an optional string for more readable debugging output. +// +func (f *Function) newBasicBlock(comment string) *BasicBlock { + b := &BasicBlock{ + Index: len(f.Blocks), + Comment: comment, + parent: f, + } + b.Succs = b.succs2[:0] + f.Blocks = append(f.Blocks, b) + return b +} + +// NewFunction returns a new synthetic Function instance belonging to +// prog, with its name and signature fields set as specified. +// +// The caller is responsible for initializing the remaining fields of +// the function object, e.g. Pkg, Params, Blocks. +// +// It is practically impossible for clients to construct well-formed +// SSA functions/packages/programs directly, so we assume this is the +// job of the Builder alone. NewFunction exists to provide clients a +// little flexibility. For example, analysis tools may wish to +// construct fake Functions for the root of the callgraph, a fake +// "reflect" package, etc. +// +// TODO(adonovan): think harder about the API here. +// +func (prog *Program) NewFunction(name string, sig *types.Signature, provenance string) *Function { + return &Function{Prog: prog, name: name, Signature: sig, Synthetic: provenance} +} + +type extentNode [2]token.Pos + +func (n extentNode) Pos() token.Pos { return n[0] } +func (n extentNode) End() token.Pos { return n[1] } + +// Syntax returns an ast.Node whose Pos/End methods provide the +// lexical extent of the function if it was defined by Go source code +// (f.Synthetic==""), or nil otherwise. +// +// If f was built with debug information (see Package.SetDebugRef), +// the result is the *ast.FuncDecl or *ast.FuncLit that declared the +// function. Otherwise, it is an opaque Node providing only position +// information; this avoids pinning the AST in memory. +// +func (f *Function) Syntax() ast.Node { return f.syntax } diff --git a/vendor/honnef.co/go/tools/ssa/identical.go b/vendor/honnef.co/go/tools/ssa/identical.go new file mode 100644 index 0000000000..53cbee107b --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/identical.go @@ -0,0 +1,7 @@ +// +build go1.8 + +package ssa + +import "go/types" + +var structTypesIdentical = types.IdenticalIgnoreTags diff --git a/vendor/honnef.co/go/tools/ssa/identical_17.go b/vendor/honnef.co/go/tools/ssa/identical_17.go new file mode 100644 index 0000000000..da89d3339a --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/identical_17.go @@ -0,0 +1,7 @@ +// +build !go1.8 + +package ssa + +import "go/types" + +var structTypesIdentical = types.Identical diff --git a/vendor/honnef.co/go/tools/ssa/lift.go b/vendor/honnef.co/go/tools/ssa/lift.go new file mode 100644 index 0000000000..048e9b0326 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/lift.go @@ -0,0 +1,653 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file defines the lifting pass which tries to "lift" Alloc +// cells (new/local variables) into SSA registers, replacing loads +// with the dominating stored value, eliminating loads and stores, and +// inserting φ-nodes as needed. + +// Cited papers and resources: +// +// Ron Cytron et al. 1991. Efficiently computing SSA form... +// http://doi.acm.org/10.1145/115372.115320 +// +// Cooper, Harvey, Kennedy. 2001. A Simple, Fast Dominance Algorithm. +// Software Practice and Experience 2001, 4:1-10. +// http://www.hipersoft.rice.edu/grads/publications/dom14.pdf +// +// Daniel Berlin, llvmdev mailing list, 2012. +// http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-January/046638.html +// (Be sure to expand the whole thread.) + +// TODO(adonovan): opt: there are many optimizations worth evaluating, and +// the conventional wisdom for SSA construction is that a simple +// algorithm well engineered often beats those of better asymptotic +// complexity on all but the most egregious inputs. +// +// Danny Berlin suggests that the Cooper et al. algorithm for +// computing the dominance frontier is superior to Cytron et al. +// Furthermore he recommends that rather than computing the DF for the +// whole function then renaming all alloc cells, it may be cheaper to +// compute the DF for each alloc cell separately and throw it away. +// +// Consider exploiting liveness information to avoid creating dead +// φ-nodes which we then immediately remove. +// +// Also see many other "TODO: opt" suggestions in the code. + +import ( + "fmt" + "go/token" + "go/types" + "math/big" + "os" +) + +// If true, show diagnostic information at each step of lifting. +// Very verbose. +const debugLifting = false + +// domFrontier maps each block to the set of blocks in its dominance +// frontier. The outer slice is conceptually a map keyed by +// Block.Index. The inner slice is conceptually a set, possibly +// containing duplicates. +// +// TODO(adonovan): opt: measure impact of dups; consider a packed bit +// representation, e.g. big.Int, and bitwise parallel operations for +// the union step in the Children loop. +// +// domFrontier's methods mutate the slice's elements but not its +// length, so their receivers needn't be pointers. +// +type domFrontier [][]*BasicBlock + +func (df domFrontier) add(u, v *BasicBlock) { + p := &df[u.Index] + *p = append(*p, v) +} + +// build builds the dominance frontier df for the dominator (sub)tree +// rooted at u, using the Cytron et al. algorithm. +// +// TODO(adonovan): opt: consider Berlin approach, computing pruned SSA +// by pruning the entire IDF computation, rather than merely pruning +// the DF -> IDF step. +func (df domFrontier) build(u *BasicBlock) { + // Encounter each node u in postorder of dom tree. + for _, child := range u.dom.children { + df.build(child) + } + for _, vb := range u.Succs { + if v := vb.dom; v.idom != u { + df.add(u, vb) + } + } + for _, w := range u.dom.children { + for _, vb := range df[w.Index] { + // TODO(adonovan): opt: use word-parallel bitwise union. + if v := vb.dom; v.idom != u { + df.add(u, vb) + } + } + } +} + +func buildDomFrontier(fn *Function) domFrontier { + df := make(domFrontier, len(fn.Blocks)) + df.build(fn.Blocks[0]) + if fn.Recover != nil { + df.build(fn.Recover) + } + return df +} + +func removeInstr(refs []Instruction, instr Instruction) []Instruction { + i := 0 + for _, ref := range refs { + if ref == instr { + continue + } + refs[i] = ref + i++ + } + for j := i; j != len(refs); j++ { + refs[j] = nil // aid GC + } + return refs[:i] +} + +// lift replaces local and new Allocs accessed only with +// load/store by SSA registers, inserting φ-nodes where necessary. +// The result is a program in classical pruned SSA form. +// +// Preconditions: +// - fn has no dead blocks (blockopt has run). +// - Def/use info (Operands and Referrers) is up-to-date. +// - The dominator tree is up-to-date. +// +func lift(fn *Function) { + // TODO(adonovan): opt: lots of little optimizations may be + // worthwhile here, especially if they cause us to avoid + // buildDomFrontier. For example: + // + // - Alloc never loaded? Eliminate. + // - Alloc never stored? Replace all loads with a zero constant. + // - Alloc stored once? Replace loads with dominating store; + // don't forget that an Alloc is itself an effective store + // of zero. + // - Alloc used only within a single block? + // Use degenerate algorithm avoiding φ-nodes. + // - Consider synergy with scalar replacement of aggregates (SRA). + // e.g. *(&x.f) where x is an Alloc. + // Perhaps we'd get better results if we generated this as x.f + // i.e. Field(x, .f) instead of Load(FieldIndex(x, .f)). + // Unclear. + // + // But we will start with the simplest correct code. + df := buildDomFrontier(fn) + + if debugLifting { + title := false + for i, blocks := range df { + if blocks != nil { + if !title { + fmt.Fprintf(os.Stderr, "Dominance frontier of %s:\n", fn) + title = true + } + fmt.Fprintf(os.Stderr, "\t%s: %s\n", fn.Blocks[i], blocks) + } + } + } + + newPhis := make(newPhiMap) + + // During this pass we will replace some BasicBlock.Instrs + // (allocs, loads and stores) with nil, keeping a count in + // BasicBlock.gaps. At the end we will reset Instrs to the + // concatenation of all non-dead newPhis and non-nil Instrs + // for the block, reusing the original array if space permits. + + // While we're here, we also eliminate 'rundefers' + // instructions in functions that contain no 'defer' + // instructions. + usesDefer := false + + // A counter used to generate ~unique ids for Phi nodes, as an + // aid to debugging. We use large numbers to make them highly + // visible. All nodes are renumbered later. + fresh := 1000 + + // Determine which allocs we can lift and number them densely. + // The renaming phase uses this numbering for compact maps. + numAllocs := 0 + for _, b := range fn.Blocks { + b.gaps = 0 + b.rundefers = 0 + for _, instr := range b.Instrs { + switch instr := instr.(type) { + case *Alloc: + index := -1 + if liftAlloc(df, instr, newPhis, &fresh) { + index = numAllocs + numAllocs++ + } + instr.index = index + case *Defer: + usesDefer = true + case *RunDefers: + b.rundefers++ + } + } + } + + // renaming maps an alloc (keyed by index) to its replacement + // value. Initially the renaming contains nil, signifying the + // zero constant of the appropriate type; we construct the + // Const lazily at most once on each path through the domtree. + // TODO(adonovan): opt: cache per-function not per subtree. + renaming := make([]Value, numAllocs) + + // Renaming. + rename(fn.Blocks[0], renaming, newPhis) + + // Eliminate dead φ-nodes. + removeDeadPhis(fn.Blocks, newPhis) + + // Prepend remaining live φ-nodes to each block. + for _, b := range fn.Blocks { + nps := newPhis[b] + j := len(nps) + + rundefersToKill := b.rundefers + if usesDefer { + rundefersToKill = 0 + } + + if j+b.gaps+rundefersToKill == 0 { + continue // fast path: no new phis or gaps + } + + // Compact nps + non-nil Instrs into a new slice. + // TODO(adonovan): opt: compact in situ (rightwards) + // if Instrs has sufficient space or slack. + dst := make([]Instruction, len(b.Instrs)+j-b.gaps-rundefersToKill) + for i, np := range nps { + dst[i] = np.phi + } + for _, instr := range b.Instrs { + if instr == nil { + continue + } + if !usesDefer { + if _, ok := instr.(*RunDefers); ok { + continue + } + } + dst[j] = instr + j++ + } + b.Instrs = dst + } + + // Remove any fn.Locals that were lifted. + j := 0 + for _, l := range fn.Locals { + if l.index < 0 { + fn.Locals[j] = l + j++ + } + } + // Nil out fn.Locals[j:] to aid GC. + for i := j; i < len(fn.Locals); i++ { + fn.Locals[i] = nil + } + fn.Locals = fn.Locals[:j] +} + +// removeDeadPhis removes φ-nodes not transitively needed by a +// non-Phi, non-DebugRef instruction. +func removeDeadPhis(blocks []*BasicBlock, newPhis newPhiMap) { + // First pass: find the set of "live" φ-nodes: those reachable + // from some non-Phi instruction. + // + // We compute reachability in reverse, starting from each φ, + // rather than forwards, starting from each live non-Phi + // instruction, because this way visits much less of the + // Value graph. + livePhis := make(map[*Phi]bool) + for _, npList := range newPhis { + for _, np := range npList { + phi := np.phi + if !livePhis[phi] && phiHasDirectReferrer(phi) { + markLivePhi(livePhis, phi) + } + } + } + + // Existing φ-nodes due to && and || operators + // are all considered live (see Go issue 19622). + for _, b := range blocks { + for _, phi := range b.phis() { + markLivePhi(livePhis, phi.(*Phi)) + } + } + + // Second pass: eliminate unused phis from newPhis. + for block, npList := range newPhis { + j := 0 + for _, np := range npList { + if livePhis[np.phi] { + npList[j] = np + j++ + } else { + // discard it, first removing it from referrers + for _, val := range np.phi.Edges { + if refs := val.Referrers(); refs != nil { + *refs = removeInstr(*refs, np.phi) + } + } + np.phi.block = nil + } + } + newPhis[block] = npList[:j] + } +} + +// markLivePhi marks phi, and all φ-nodes transitively reachable via +// its Operands, live. +func markLivePhi(livePhis map[*Phi]bool, phi *Phi) { + livePhis[phi] = true + for _, rand := range phi.Operands(nil) { + if q, ok := (*rand).(*Phi); ok { + if !livePhis[q] { + markLivePhi(livePhis, q) + } + } + } +} + +// phiHasDirectReferrer reports whether phi is directly referred to by +// a non-Phi instruction. Such instructions are the +// roots of the liveness traversal. +func phiHasDirectReferrer(phi *Phi) bool { + for _, instr := range *phi.Referrers() { + if _, ok := instr.(*Phi); !ok { + return true + } + } + return false +} + +type blockSet struct{ big.Int } // (inherit methods from Int) + +// add adds b to the set and returns true if the set changed. +func (s *blockSet) add(b *BasicBlock) bool { + i := b.Index + if s.Bit(i) != 0 { + return false + } + s.SetBit(&s.Int, i, 1) + return true +} + +// take removes an arbitrary element from a set s and +// returns its index, or returns -1 if empty. +func (s *blockSet) take() int { + l := s.BitLen() + for i := 0; i < l; i++ { + if s.Bit(i) == 1 { + s.SetBit(&s.Int, i, 0) + return i + } + } + return -1 +} + +// newPhi is a pair of a newly introduced φ-node and the lifted Alloc +// it replaces. +type newPhi struct { + phi *Phi + alloc *Alloc +} + +// newPhiMap records for each basic block, the set of newPhis that +// must be prepended to the block. +type newPhiMap map[*BasicBlock][]newPhi + +// liftAlloc determines whether alloc can be lifted into registers, +// and if so, it populates newPhis with all the φ-nodes it may require +// and returns true. +// +// fresh is a source of fresh ids for phi nodes. +// +func liftAlloc(df domFrontier, alloc *Alloc, newPhis newPhiMap, fresh *int) bool { + // Don't lift aggregates into registers, because we don't have + // a way to express their zero-constants. + switch deref(alloc.Type()).Underlying().(type) { + case *types.Array, *types.Struct: + return false + } + + // Don't lift named return values in functions that defer + // calls that may recover from panic. + if fn := alloc.Parent(); fn.Recover != nil { + for _, nr := range fn.namedResults { + if nr == alloc { + return false + } + } + } + + // Compute defblocks, the set of blocks containing a + // definition of the alloc cell. + var defblocks blockSet + for _, instr := range *alloc.Referrers() { + // Bail out if we discover the alloc is not liftable; + // the only operations permitted to use the alloc are + // loads/stores into the cell, and DebugRef. + switch instr := instr.(type) { + case *Store: + if instr.Val == alloc { + return false // address used as value + } + if instr.Addr != alloc { + panic("Alloc.Referrers is inconsistent") + } + defblocks.add(instr.Block()) + case *UnOp: + if instr.Op != token.MUL { + return false // not a load + } + if instr.X != alloc { + panic("Alloc.Referrers is inconsistent") + } + case *DebugRef: + // ok + default: + return false // some other instruction + } + } + // The Alloc itself counts as a (zero) definition of the cell. + defblocks.add(alloc.Block()) + + if debugLifting { + fmt.Fprintln(os.Stderr, "\tlifting ", alloc, alloc.Name()) + } + + fn := alloc.Parent() + + // Φ-insertion. + // + // What follows is the body of the main loop of the insert-φ + // function described by Cytron et al, but instead of using + // counter tricks, we just reset the 'hasAlready' and 'work' + // sets each iteration. These are bitmaps so it's pretty cheap. + // + // TODO(adonovan): opt: recycle slice storage for W, + // hasAlready, defBlocks across liftAlloc calls. + var hasAlready blockSet + + // Initialize W and work to defblocks. + var work blockSet = defblocks // blocks seen + var W blockSet // blocks to do + W.Set(&defblocks.Int) + + // Traverse iterated dominance frontier, inserting φ-nodes. + for i := W.take(); i != -1; i = W.take() { + u := fn.Blocks[i] + for _, v := range df[u.Index] { + if hasAlready.add(v) { + // Create φ-node. + // It will be prepended to v.Instrs later, if needed. + phi := &Phi{ + Edges: make([]Value, len(v.Preds)), + Comment: alloc.Comment, + } + // This is merely a debugging aid: + phi.setNum(*fresh) + *fresh++ + + phi.pos = alloc.Pos() + phi.setType(deref(alloc.Type())) + phi.block = v + if debugLifting { + fmt.Fprintf(os.Stderr, "\tplace %s = %s at block %s\n", phi.Name(), phi, v) + } + newPhis[v] = append(newPhis[v], newPhi{phi, alloc}) + + if work.add(v) { + W.add(v) + } + } + } + } + + return true +} + +// replaceAll replaces all intraprocedural uses of x with y, +// updating x.Referrers and y.Referrers. +// Precondition: x.Referrers() != nil, i.e. x must be local to some function. +// +func replaceAll(x, y Value) { + var rands []*Value + pxrefs := x.Referrers() + pyrefs := y.Referrers() + for _, instr := range *pxrefs { + rands = instr.Operands(rands[:0]) // recycle storage + for _, rand := range rands { + if *rand != nil { + if *rand == x { + *rand = y + } + } + } + if pyrefs != nil { + *pyrefs = append(*pyrefs, instr) // dups ok + } + } + *pxrefs = nil // x is now unreferenced +} + +// renamed returns the value to which alloc is being renamed, +// constructing it lazily if it's the implicit zero initialization. +// +func renamed(renaming []Value, alloc *Alloc) Value { + v := renaming[alloc.index] + if v == nil { + v = zeroConst(deref(alloc.Type())) + renaming[alloc.index] = v + } + return v +} + +// rename implements the (Cytron et al) SSA renaming algorithm, a +// preorder traversal of the dominator tree replacing all loads of +// Alloc cells with the value stored to that cell by the dominating +// store instruction. For lifting, we need only consider loads, +// stores and φ-nodes. +// +// renaming is a map from *Alloc (keyed by index number) to its +// dominating stored value; newPhis[x] is the set of new φ-nodes to be +// prepended to block x. +// +func rename(u *BasicBlock, renaming []Value, newPhis newPhiMap) { + // Each φ-node becomes the new name for its associated Alloc. + for _, np := range newPhis[u] { + phi := np.phi + alloc := np.alloc + renaming[alloc.index] = phi + } + + // Rename loads and stores of allocs. + for i, instr := range u.Instrs { + switch instr := instr.(type) { + case *Alloc: + if instr.index >= 0 { // store of zero to Alloc cell + // Replace dominated loads by the zero value. + renaming[instr.index] = nil + if debugLifting { + fmt.Fprintf(os.Stderr, "\tkill alloc %s\n", instr) + } + // Delete the Alloc. + u.Instrs[i] = nil + u.gaps++ + } + + case *Store: + if alloc, ok := instr.Addr.(*Alloc); ok && alloc.index >= 0 { // store to Alloc cell + // Replace dominated loads by the stored value. + renaming[alloc.index] = instr.Val + if debugLifting { + fmt.Fprintf(os.Stderr, "\tkill store %s; new value: %s\n", + instr, instr.Val.Name()) + } + // Remove the store from the referrer list of the stored value. + if refs := instr.Val.Referrers(); refs != nil { + *refs = removeInstr(*refs, instr) + } + // Delete the Store. + u.Instrs[i] = nil + u.gaps++ + } + + case *UnOp: + if instr.Op == token.MUL { + if alloc, ok := instr.X.(*Alloc); ok && alloc.index >= 0 { // load of Alloc cell + newval := renamed(renaming, alloc) + if debugLifting { + fmt.Fprintf(os.Stderr, "\tupdate load %s = %s with %s\n", + instr.Name(), instr, newval.Name()) + } + // Replace all references to + // the loaded value by the + // dominating stored value. + replaceAll(instr, newval) + // Delete the Load. + u.Instrs[i] = nil + u.gaps++ + } + } + + case *DebugRef: + if alloc, ok := instr.X.(*Alloc); ok && alloc.index >= 0 { // ref of Alloc cell + if instr.IsAddr { + instr.X = renamed(renaming, alloc) + instr.IsAddr = false + + // Add DebugRef to instr.X's referrers. + if refs := instr.X.Referrers(); refs != nil { + *refs = append(*refs, instr) + } + } else { + // A source expression denotes the address + // of an Alloc that was optimized away. + instr.X = nil + + // Delete the DebugRef. + u.Instrs[i] = nil + u.gaps++ + } + } + } + } + + // For each φ-node in a CFG successor, rename the edge. + for _, v := range u.Succs { + phis := newPhis[v] + if len(phis) == 0 { + continue + } + i := v.predIndex(u) + for _, np := range phis { + phi := np.phi + alloc := np.alloc + newval := renamed(renaming, alloc) + if debugLifting { + fmt.Fprintf(os.Stderr, "\tsetphi %s edge %s -> %s (#%d) (alloc=%s) := %s\n", + phi.Name(), u, v, i, alloc.Name(), newval.Name()) + } + phi.Edges[i] = newval + if prefs := newval.Referrers(); prefs != nil { + *prefs = append(*prefs, phi) + } + } + } + + // Continue depth-first recursion over domtree, pushing a + // fresh copy of the renaming map for each subtree. + for i, v := range u.dom.children { + r := renaming + if i < len(u.dom.children)-1 { + // On all but the final iteration, we must make + // a copy to avoid destructive update. + r = make([]Value, len(renaming)) + copy(r, renaming) + } + rename(v, r, newPhis) + } + +} diff --git a/vendor/honnef.co/go/tools/ssa/lvalue.go b/vendor/honnef.co/go/tools/ssa/lvalue.go new file mode 100644 index 0000000000..eb5d71e188 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/lvalue.go @@ -0,0 +1,123 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// lvalues are the union of addressable expressions and map-index +// expressions. + +import ( + "go/ast" + "go/token" + "go/types" +) + +// An lvalue represents an assignable location that may appear on the +// left-hand side of an assignment. This is a generalization of a +// pointer to permit updates to elements of maps. +// +type lvalue interface { + store(fn *Function, v Value) // stores v into the location + load(fn *Function) Value // loads the contents of the location + address(fn *Function) Value // address of the location + typ() types.Type // returns the type of the location +} + +// An address is an lvalue represented by a true pointer. +type address struct { + addr Value + pos token.Pos // source position + expr ast.Expr // source syntax of the value (not address) [debug mode] +} + +func (a *address) load(fn *Function) Value { + load := emitLoad(fn, a.addr) + load.pos = a.pos + return load +} + +func (a *address) store(fn *Function, v Value) { + store := emitStore(fn, a.addr, v, a.pos) + if a.expr != nil { + // store.Val is v, converted for assignability. + emitDebugRef(fn, a.expr, store.Val, false) + } +} + +func (a *address) address(fn *Function) Value { + if a.expr != nil { + emitDebugRef(fn, a.expr, a.addr, true) + } + return a.addr +} + +func (a *address) typ() types.Type { + return deref(a.addr.Type()) +} + +// An element is an lvalue represented by m[k], the location of an +// element of a map or string. These locations are not addressable +// since pointers cannot be formed from them, but they do support +// load(), and in the case of maps, store(). +// +type element struct { + m, k Value // map or string + t types.Type // map element type or string byte type + pos token.Pos // source position of colon ({k:v}) or lbrack (m[k]=v) +} + +func (e *element) load(fn *Function) Value { + l := &Lookup{ + X: e.m, + Index: e.k, + } + l.setPos(e.pos) + l.setType(e.t) + return fn.emit(l) +} + +func (e *element) store(fn *Function, v Value) { + up := &MapUpdate{ + Map: e.m, + Key: e.k, + Value: emitConv(fn, v, e.t), + } + up.pos = e.pos + fn.emit(up) +} + +func (e *element) address(fn *Function) Value { + panic("map/string elements are not addressable") +} + +func (e *element) typ() types.Type { + return e.t +} + +// A blank is a dummy variable whose name is "_". +// It is not reified: loads are illegal and stores are ignored. +// +type blank struct{} + +func (bl blank) load(fn *Function) Value { + panic("blank.load is illegal") +} + +func (bl blank) store(fn *Function, v Value) { + s := &BlankStore{ + Val: v, + } + fn.emit(s) +} + +func (bl blank) address(fn *Function) Value { + panic("blank var is not addressable") +} + +func (bl blank) typ() types.Type { + // This should be the type of the blank Ident; the typechecker + // doesn't provide this yet, but fortunately, we don't need it + // yet either. + panic("blank.typ is unimplemented") +} diff --git a/vendor/honnef.co/go/tools/ssa/methods.go b/vendor/honnef.co/go/tools/ssa/methods.go new file mode 100644 index 0000000000..080dca968e --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/methods.go @@ -0,0 +1,239 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file defines utilities for population of method sets. + +import ( + "fmt" + "go/types" +) + +// MethodValue returns the Function implementing method sel, building +// wrapper methods on demand. It returns nil if sel denotes an +// abstract (interface) method. +// +// Precondition: sel.Kind() == MethodVal. +// +// Thread-safe. +// +// EXCLUSIVE_LOCKS_ACQUIRED(prog.methodsMu) +// +func (prog *Program) MethodValue(sel *types.Selection) *Function { + if sel.Kind() != types.MethodVal { + panic(fmt.Sprintf("Method(%s) kind != MethodVal", sel)) + } + T := sel.Recv() + if isInterface(T) { + return nil // abstract method + } + if prog.mode&LogSource != 0 { + defer logStack("Method %s %v", T, sel)() + } + + prog.methodsMu.Lock() + defer prog.methodsMu.Unlock() + + return prog.addMethod(prog.createMethodSet(T), sel) +} + +// LookupMethod returns the implementation of the method of type T +// identified by (pkg, name). It returns nil if the method exists but +// is abstract, and panics if T has no such method. +// +func (prog *Program) LookupMethod(T types.Type, pkg *types.Package, name string) *Function { + sel := prog.MethodSets.MethodSet(T).Lookup(pkg, name) + if sel == nil { + panic(fmt.Sprintf("%s has no method %s", T, types.Id(pkg, name))) + } + return prog.MethodValue(sel) +} + +// methodSet contains the (concrete) methods of a non-interface type. +type methodSet struct { + mapping map[string]*Function // populated lazily + complete bool // mapping contains all methods +} + +// Precondition: !isInterface(T). +// EXCLUSIVE_LOCKS_REQUIRED(prog.methodsMu) +func (prog *Program) createMethodSet(T types.Type) *methodSet { + mset, ok := prog.methodSets.At(T).(*methodSet) + if !ok { + mset = &methodSet{mapping: make(map[string]*Function)} + prog.methodSets.Set(T, mset) + } + return mset +} + +// EXCLUSIVE_LOCKS_REQUIRED(prog.methodsMu) +func (prog *Program) addMethod(mset *methodSet, sel *types.Selection) *Function { + if sel.Kind() == types.MethodExpr { + panic(sel) + } + id := sel.Obj().Id() + fn := mset.mapping[id] + if fn == nil { + obj := sel.Obj().(*types.Func) + + needsPromotion := len(sel.Index()) > 1 + needsIndirection := !isPointer(recvType(obj)) && isPointer(sel.Recv()) + if needsPromotion || needsIndirection { + fn = makeWrapper(prog, sel) + } else { + fn = prog.declaredFunc(obj) + } + if fn.Signature.Recv() == nil { + panic(fn) // missing receiver + } + mset.mapping[id] = fn + } + return fn +} + +// RuntimeTypes returns a new unordered slice containing all +// concrete types in the program for which a complete (non-empty) +// method set is required at run-time. +// +// Thread-safe. +// +// EXCLUSIVE_LOCKS_ACQUIRED(prog.methodsMu) +// +func (prog *Program) RuntimeTypes() []types.Type { + prog.methodsMu.Lock() + defer prog.methodsMu.Unlock() + + var res []types.Type + prog.methodSets.Iterate(func(T types.Type, v interface{}) { + if v.(*methodSet).complete { + res = append(res, T) + } + }) + return res +} + +// declaredFunc returns the concrete function/method denoted by obj. +// Panic ensues if there is none. +// +func (prog *Program) declaredFunc(obj *types.Func) *Function { + if v := prog.packageLevelValue(obj); v != nil { + return v.(*Function) + } + panic("no concrete method: " + obj.String()) +} + +// needMethodsOf ensures that runtime type information (including the +// complete method set) is available for the specified type T and all +// its subcomponents. +// +// needMethodsOf must be called for at least every type that is an +// operand of some MakeInterface instruction, and for the type of +// every exported package member. +// +// Precondition: T is not a method signature (*Signature with Recv()!=nil). +// +// Thread-safe. (Called via emitConv from multiple builder goroutines.) +// +// TODO(adonovan): make this faster. It accounts for 20% of SSA build time. +// +// EXCLUSIVE_LOCKS_ACQUIRED(prog.methodsMu) +// +func (prog *Program) needMethodsOf(T types.Type) { + prog.methodsMu.Lock() + prog.needMethods(T, false) + prog.methodsMu.Unlock() +} + +// Precondition: T is not a method signature (*Signature with Recv()!=nil). +// Recursive case: skip => don't create methods for T. +// +// EXCLUSIVE_LOCKS_REQUIRED(prog.methodsMu) +// +func (prog *Program) needMethods(T types.Type, skip bool) { + // Each package maintains its own set of types it has visited. + if prevSkip, ok := prog.runtimeTypes.At(T).(bool); ok { + // needMethods(T) was previously called + if !prevSkip || skip { + return // already seen, with same or false 'skip' value + } + } + prog.runtimeTypes.Set(T, skip) + + tmset := prog.MethodSets.MethodSet(T) + + if !skip && !isInterface(T) && tmset.Len() > 0 { + // Create methods of T. + mset := prog.createMethodSet(T) + if !mset.complete { + mset.complete = true + n := tmset.Len() + for i := 0; i < n; i++ { + prog.addMethod(mset, tmset.At(i)) + } + } + } + + // Recursion over signatures of each method. + for i := 0; i < tmset.Len(); i++ { + sig := tmset.At(i).Type().(*types.Signature) + prog.needMethods(sig.Params(), false) + prog.needMethods(sig.Results(), false) + } + + switch t := T.(type) { + case *types.Basic: + // nop + + case *types.Interface: + // nop---handled by recursion over method set. + + case *types.Pointer: + prog.needMethods(t.Elem(), false) + + case *types.Slice: + prog.needMethods(t.Elem(), false) + + case *types.Chan: + prog.needMethods(t.Elem(), false) + + case *types.Map: + prog.needMethods(t.Key(), false) + prog.needMethods(t.Elem(), false) + + case *types.Signature: + if t.Recv() != nil { + panic(fmt.Sprintf("Signature %s has Recv %s", t, t.Recv())) + } + prog.needMethods(t.Params(), false) + prog.needMethods(t.Results(), false) + + case *types.Named: + // A pointer-to-named type can be derived from a named + // type via reflection. It may have methods too. + prog.needMethods(types.NewPointer(T), false) + + // Consider 'type T struct{S}' where S has methods. + // Reflection provides no way to get from T to struct{S}, + // only to S, so the method set of struct{S} is unwanted, + // so set 'skip' flag during recursion. + prog.needMethods(t.Underlying(), true) + + case *types.Array: + prog.needMethods(t.Elem(), false) + + case *types.Struct: + for i, n := 0, t.NumFields(); i < n; i++ { + prog.needMethods(t.Field(i).Type(), false) + } + + case *types.Tuple: + for i, n := 0, t.Len(); i < n; i++ { + prog.needMethods(t.At(i).Type(), false) + } + + default: + panic(T) + } +} diff --git a/vendor/honnef.co/go/tools/ssa/mode.go b/vendor/honnef.co/go/tools/ssa/mode.go new file mode 100644 index 0000000000..d2a269893a --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/mode.go @@ -0,0 +1,100 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file defines the BuilderMode type and its command-line flag. + +import ( + "bytes" + "fmt" +) + +// BuilderMode is a bitmask of options for diagnostics and checking. +// +// *BuilderMode satisfies the flag.Value interface. Example: +// +// var mode = ssa.BuilderMode(0) +// func init() { flag.Var(&mode, "build", ssa.BuilderModeDoc) } +// +type BuilderMode uint + +const ( + PrintPackages BuilderMode = 1 << iota // Print package inventory to stdout + PrintFunctions // Print function SSA code to stdout + LogSource // Log source locations as SSA builder progresses + SanityCheckFunctions // Perform sanity checking of function bodies + NaiveForm // Build naïve SSA form: don't replace local loads/stores with registers + BuildSerially // Build packages serially, not in parallel. + GlobalDebug // Enable debug info for all packages + BareInits // Build init functions without guards or calls to dependent inits +) + +const BuilderModeDoc = `Options controlling the SSA builder. +The value is a sequence of zero or more of these letters: +C perform sanity [C]hecking of the SSA form. +D include [D]ebug info for every function. +P print [P]ackage inventory. +F print [F]unction SSA code. +S log [S]ource locations as SSA builder progresses. +L build distinct packages seria[L]ly instead of in parallel. +N build [N]aive SSA form: don't replace local loads/stores with registers. +I build bare [I]nit functions: no init guards or calls to dependent inits. +` + +func (m BuilderMode) String() string { + var buf bytes.Buffer + if m&GlobalDebug != 0 { + buf.WriteByte('D') + } + if m&PrintPackages != 0 { + buf.WriteByte('P') + } + if m&PrintFunctions != 0 { + buf.WriteByte('F') + } + if m&LogSource != 0 { + buf.WriteByte('S') + } + if m&SanityCheckFunctions != 0 { + buf.WriteByte('C') + } + if m&NaiveForm != 0 { + buf.WriteByte('N') + } + if m&BuildSerially != 0 { + buf.WriteByte('L') + } + return buf.String() +} + +// Set parses the flag characters in s and updates *m. +func (m *BuilderMode) Set(s string) error { + var mode BuilderMode + for _, c := range s { + switch c { + case 'D': + mode |= GlobalDebug + case 'P': + mode |= PrintPackages + case 'F': + mode |= PrintFunctions + case 'S': + mode |= LogSource | BuildSerially + case 'C': + mode |= SanityCheckFunctions + case 'N': + mode |= NaiveForm + case 'L': + mode |= BuildSerially + default: + return fmt.Errorf("unknown BuilderMode option: %q", c) + } + } + *m = mode + return nil +} + +// Get returns m. +func (m BuilderMode) Get() interface{} { return m } diff --git a/vendor/honnef.co/go/tools/ssa/print.go b/vendor/honnef.co/go/tools/ssa/print.go new file mode 100644 index 0000000000..6fd277277c --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/print.go @@ -0,0 +1,435 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file implements the String() methods for all Value and +// Instruction types. + +import ( + "bytes" + "fmt" + "go/types" + "io" + "reflect" + "sort" + + "golang.org/x/tools/go/types/typeutil" +) + +// relName returns the name of v relative to i. +// In most cases, this is identical to v.Name(), but references to +// Functions (including methods) and Globals use RelString and +// all types are displayed with relType, so that only cross-package +// references are package-qualified. +// +func relName(v Value, i Instruction) string { + var from *types.Package + if i != nil { + from = i.Parent().pkg() + } + switch v := v.(type) { + case Member: // *Function or *Global + return v.RelString(from) + case *Const: + return v.RelString(from) + } + return v.Name() +} + +func relType(t types.Type, from *types.Package) string { + return types.TypeString(t, types.RelativeTo(from)) +} + +func relString(m Member, from *types.Package) string { + // NB: not all globals have an Object (e.g. init$guard), + // so use Package().Object not Object.Package(). + if pkg := m.Package().Pkg; pkg != nil && pkg != from { + return fmt.Sprintf("%s.%s", pkg.Path(), m.Name()) + } + return m.Name() +} + +// Value.String() +// +// This method is provided only for debugging. +// It never appears in disassembly, which uses Value.Name(). + +func (v *Parameter) String() string { + from := v.Parent().pkg() + return fmt.Sprintf("parameter %s : %s", v.Name(), relType(v.Type(), from)) +} + +func (v *FreeVar) String() string { + from := v.Parent().pkg() + return fmt.Sprintf("freevar %s : %s", v.Name(), relType(v.Type(), from)) +} + +func (v *Builtin) String() string { + return fmt.Sprintf("builtin %s", v.Name()) +} + +// Instruction.String() + +func (v *Alloc) String() string { + op := "local" + if v.Heap { + op = "new" + } + from := v.Parent().pkg() + return fmt.Sprintf("%s %s (%s)", op, relType(deref(v.Type()), from), v.Comment) +} + +func (v *Phi) String() string { + var b bytes.Buffer + b.WriteString("phi [") + for i, edge := range v.Edges { + if i > 0 { + b.WriteString(", ") + } + // Be robust against malformed CFG. + if v.block == nil { + b.WriteString("??") + continue + } + block := -1 + if i < len(v.block.Preds) { + block = v.block.Preds[i].Index + } + fmt.Fprintf(&b, "%d: ", block) + edgeVal := "" // be robust + if edge != nil { + edgeVal = relName(edge, v) + } + b.WriteString(edgeVal) + } + b.WriteString("]") + if v.Comment != "" { + b.WriteString(" #") + b.WriteString(v.Comment) + } + return b.String() +} + +func printCall(v *CallCommon, prefix string, instr Instruction) string { + var b bytes.Buffer + b.WriteString(prefix) + if !v.IsInvoke() { + b.WriteString(relName(v.Value, instr)) + } else { + fmt.Fprintf(&b, "invoke %s.%s", relName(v.Value, instr), v.Method.Name()) + } + b.WriteString("(") + for i, arg := range v.Args { + if i > 0 { + b.WriteString(", ") + } + b.WriteString(relName(arg, instr)) + } + if v.Signature().Variadic() { + b.WriteString("...") + } + b.WriteString(")") + return b.String() +} + +func (c *CallCommon) String() string { + return printCall(c, "", nil) +} + +func (v *Call) String() string { + return printCall(&v.Call, "", v) +} + +func (v *BinOp) String() string { + return fmt.Sprintf("%s %s %s", relName(v.X, v), v.Op.String(), relName(v.Y, v)) +} + +func (v *UnOp) String() string { + return fmt.Sprintf("%s%s%s", v.Op, relName(v.X, v), commaOk(v.CommaOk)) +} + +func printConv(prefix string, v, x Value) string { + from := v.Parent().pkg() + return fmt.Sprintf("%s %s <- %s (%s)", + prefix, + relType(v.Type(), from), + relType(x.Type(), from), + relName(x, v.(Instruction))) +} + +func (v *ChangeType) String() string { return printConv("changetype", v, v.X) } +func (v *Convert) String() string { return printConv("convert", v, v.X) } +func (v *ChangeInterface) String() string { return printConv("change interface", v, v.X) } +func (v *MakeInterface) String() string { return printConv("make", v, v.X) } + +func (v *MakeClosure) String() string { + var b bytes.Buffer + fmt.Fprintf(&b, "make closure %s", relName(v.Fn, v)) + if v.Bindings != nil { + b.WriteString(" [") + for i, c := range v.Bindings { + if i > 0 { + b.WriteString(", ") + } + b.WriteString(relName(c, v)) + } + b.WriteString("]") + } + return b.String() +} + +func (v *MakeSlice) String() string { + from := v.Parent().pkg() + return fmt.Sprintf("make %s %s %s", + relType(v.Type(), from), + relName(v.Len, v), + relName(v.Cap, v)) +} + +func (v *Slice) String() string { + var b bytes.Buffer + b.WriteString("slice ") + b.WriteString(relName(v.X, v)) + b.WriteString("[") + if v.Low != nil { + b.WriteString(relName(v.Low, v)) + } + b.WriteString(":") + if v.High != nil { + b.WriteString(relName(v.High, v)) + } + if v.Max != nil { + b.WriteString(":") + b.WriteString(relName(v.Max, v)) + } + b.WriteString("]") + return b.String() +} + +func (v *MakeMap) String() string { + res := "" + if v.Reserve != nil { + res = relName(v.Reserve, v) + } + from := v.Parent().pkg() + return fmt.Sprintf("make %s %s", relType(v.Type(), from), res) +} + +func (v *MakeChan) String() string { + from := v.Parent().pkg() + return fmt.Sprintf("make %s %s", relType(v.Type(), from), relName(v.Size, v)) +} + +func (v *FieldAddr) String() string { + st := deref(v.X.Type()).Underlying().(*types.Struct) + // Be robust against a bad index. + name := "?" + if 0 <= v.Field && v.Field < st.NumFields() { + name = st.Field(v.Field).Name() + } + return fmt.Sprintf("&%s.%s [#%d]", relName(v.X, v), name, v.Field) +} + +func (v *Field) String() string { + st := v.X.Type().Underlying().(*types.Struct) + // Be robust against a bad index. + name := "?" + if 0 <= v.Field && v.Field < st.NumFields() { + name = st.Field(v.Field).Name() + } + return fmt.Sprintf("%s.%s [#%d]", relName(v.X, v), name, v.Field) +} + +func (v *IndexAddr) String() string { + return fmt.Sprintf("&%s[%s]", relName(v.X, v), relName(v.Index, v)) +} + +func (v *Index) String() string { + return fmt.Sprintf("%s[%s]", relName(v.X, v), relName(v.Index, v)) +} + +func (v *Lookup) String() string { + return fmt.Sprintf("%s[%s]%s", relName(v.X, v), relName(v.Index, v), commaOk(v.CommaOk)) +} + +func (v *Range) String() string { + return "range " + relName(v.X, v) +} + +func (v *Next) String() string { + return "next " + relName(v.Iter, v) +} + +func (v *TypeAssert) String() string { + from := v.Parent().pkg() + return fmt.Sprintf("typeassert%s %s.(%s)", commaOk(v.CommaOk), relName(v.X, v), relType(v.AssertedType, from)) +} + +func (v *Extract) String() string { + return fmt.Sprintf("extract %s #%d", relName(v.Tuple, v), v.Index) +} + +func (s *Jump) String() string { + // Be robust against malformed CFG. + block := -1 + if s.block != nil && len(s.block.Succs) == 1 { + block = s.block.Succs[0].Index + } + return fmt.Sprintf("jump %d", block) +} + +func (s *If) String() string { + // Be robust against malformed CFG. + tblock, fblock := -1, -1 + if s.block != nil && len(s.block.Succs) == 2 { + tblock = s.block.Succs[0].Index + fblock = s.block.Succs[1].Index + } + return fmt.Sprintf("if %s goto %d else %d", relName(s.Cond, s), tblock, fblock) +} + +func (s *Go) String() string { + return printCall(&s.Call, "go ", s) +} + +func (s *Panic) String() string { + return "panic " + relName(s.X, s) +} + +func (s *Return) String() string { + var b bytes.Buffer + b.WriteString("return") + for i, r := range s.Results { + if i == 0 { + b.WriteString(" ") + } else { + b.WriteString(", ") + } + b.WriteString(relName(r, s)) + } + return b.String() +} + +func (*RunDefers) String() string { + return "rundefers" +} + +func (s *Send) String() string { + return fmt.Sprintf("send %s <- %s", relName(s.Chan, s), relName(s.X, s)) +} + +func (s *Defer) String() string { + return printCall(&s.Call, "defer ", s) +} + +func (s *Select) String() string { + var b bytes.Buffer + for i, st := range s.States { + if i > 0 { + b.WriteString(", ") + } + if st.Dir == types.RecvOnly { + b.WriteString("<-") + b.WriteString(relName(st.Chan, s)) + } else { + b.WriteString(relName(st.Chan, s)) + b.WriteString("<-") + b.WriteString(relName(st.Send, s)) + } + } + non := "" + if !s.Blocking { + non = "non" + } + return fmt.Sprintf("select %sblocking [%s]", non, b.String()) +} + +func (s *Store) String() string { + return fmt.Sprintf("*%s = %s", relName(s.Addr, s), relName(s.Val, s)) +} + +func (s *BlankStore) String() string { + return fmt.Sprintf("_ = %s", relName(s.Val, s)) +} + +func (s *MapUpdate) String() string { + return fmt.Sprintf("%s[%s] = %s", relName(s.Map, s), relName(s.Key, s), relName(s.Value, s)) +} + +func (s *DebugRef) String() string { + p := s.Parent().Prog.Fset.Position(s.Pos()) + var descr interface{} + if s.object != nil { + descr = s.object // e.g. "var x int" + } else { + descr = reflect.TypeOf(s.Expr) // e.g. "*ast.CallExpr" + } + var addr string + if s.IsAddr { + addr = "address of " + } + return fmt.Sprintf("; %s%s @ %d:%d is %s", addr, descr, p.Line, p.Column, s.X.Name()) +} + +func (p *Package) String() string { + return "package " + p.Pkg.Path() +} + +var _ io.WriterTo = (*Package)(nil) // *Package implements io.Writer + +func (p *Package) WriteTo(w io.Writer) (int64, error) { + var buf bytes.Buffer + WritePackage(&buf, p) + n, err := w.Write(buf.Bytes()) + return int64(n), err +} + +// WritePackage writes to buf a human-readable summary of p. +func WritePackage(buf *bytes.Buffer, p *Package) { + fmt.Fprintf(buf, "%s:\n", p) + + var names []string + maxname := 0 + for name := range p.Members { + if l := len(name); l > maxname { + maxname = l + } + names = append(names, name) + } + + from := p.Pkg + sort.Strings(names) + for _, name := range names { + switch mem := p.Members[name].(type) { + case *NamedConst: + fmt.Fprintf(buf, " const %-*s %s = %s\n", + maxname, name, mem.Name(), mem.Value.RelString(from)) + + case *Function: + fmt.Fprintf(buf, " func %-*s %s\n", + maxname, name, relType(mem.Type(), from)) + + case *Type: + fmt.Fprintf(buf, " type %-*s %s\n", + maxname, name, relType(mem.Type().Underlying(), from)) + for _, meth := range typeutil.IntuitiveMethodSet(mem.Type(), &p.Prog.MethodSets) { + fmt.Fprintf(buf, " %s\n", types.SelectionString(meth, types.RelativeTo(from))) + } + + case *Global: + fmt.Fprintf(buf, " var %-*s %s\n", + maxname, name, relType(mem.Type().(*types.Pointer).Elem(), from)) + } + } + + fmt.Fprintf(buf, "\n") +} + +func commaOk(x bool) string { + if x { + return ",ok" + } + return "" +} diff --git a/vendor/honnef.co/go/tools/ssa/sanity.go b/vendor/honnef.co/go/tools/ssa/sanity.go new file mode 100644 index 0000000000..c56b2682c0 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/sanity.go @@ -0,0 +1,523 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// An optional pass for sanity-checking invariants of the SSA representation. +// Currently it checks CFG invariants but little at the instruction level. + +import ( + "fmt" + "go/types" + "io" + "os" + "strings" +) + +type sanity struct { + reporter io.Writer + fn *Function + block *BasicBlock + instrs map[Instruction]struct{} + insane bool +} + +// sanityCheck performs integrity checking of the SSA representation +// of the function fn and returns true if it was valid. Diagnostics +// are written to reporter if non-nil, os.Stderr otherwise. Some +// diagnostics are only warnings and do not imply a negative result. +// +// Sanity-checking is intended to facilitate the debugging of code +// transformation passes. +// +func sanityCheck(fn *Function, reporter io.Writer) bool { + if reporter == nil { + reporter = os.Stderr + } + return (&sanity{reporter: reporter}).checkFunction(fn) +} + +// mustSanityCheck is like sanityCheck but panics instead of returning +// a negative result. +// +func mustSanityCheck(fn *Function, reporter io.Writer) { + if !sanityCheck(fn, reporter) { + fn.WriteTo(os.Stderr) + panic("SanityCheck failed") + } +} + +func (s *sanity) diagnostic(prefix, format string, args ...interface{}) { + fmt.Fprintf(s.reporter, "%s: function %s", prefix, s.fn) + if s.block != nil { + fmt.Fprintf(s.reporter, ", block %s", s.block) + } + io.WriteString(s.reporter, ": ") + fmt.Fprintf(s.reporter, format, args...) + io.WriteString(s.reporter, "\n") +} + +func (s *sanity) errorf(format string, args ...interface{}) { + s.insane = true + s.diagnostic("Error", format, args...) +} + +func (s *sanity) warnf(format string, args ...interface{}) { + s.diagnostic("Warning", format, args...) +} + +// findDuplicate returns an arbitrary basic block that appeared more +// than once in blocks, or nil if all were unique. +func findDuplicate(blocks []*BasicBlock) *BasicBlock { + if len(blocks) < 2 { + return nil + } + if blocks[0] == blocks[1] { + return blocks[0] + } + // Slow path: + m := make(map[*BasicBlock]bool) + for _, b := range blocks { + if m[b] { + return b + } + m[b] = true + } + return nil +} + +func (s *sanity) checkInstr(idx int, instr Instruction) { + switch instr := instr.(type) { + case *If, *Jump, *Return, *Panic: + s.errorf("control flow instruction not at end of block") + case *Phi: + if idx == 0 { + // It suffices to apply this check to just the first phi node. + if dup := findDuplicate(s.block.Preds); dup != nil { + s.errorf("phi node in block with duplicate predecessor %s", dup) + } + } else { + prev := s.block.Instrs[idx-1] + if _, ok := prev.(*Phi); !ok { + s.errorf("Phi instruction follows a non-Phi: %T", prev) + } + } + if ne, np := len(instr.Edges), len(s.block.Preds); ne != np { + s.errorf("phi node has %d edges but %d predecessors", ne, np) + + } else { + for i, e := range instr.Edges { + if e == nil { + s.errorf("phi node '%s' has no value for edge #%d from %s", instr.Comment, i, s.block.Preds[i]) + } + } + } + + case *Alloc: + if !instr.Heap { + found := false + for _, l := range s.fn.Locals { + if l == instr { + found = true + break + } + } + if !found { + s.errorf("local alloc %s = %s does not appear in Function.Locals", instr.Name(), instr) + } + } + + case *BinOp: + case *Call: + case *ChangeInterface: + case *ChangeType: + case *Convert: + if _, ok := instr.X.Type().Underlying().(*types.Basic); !ok { + if _, ok := instr.Type().Underlying().(*types.Basic); !ok { + s.errorf("convert %s -> %s: at least one type must be basic", instr.X.Type(), instr.Type()) + } + } + + case *Defer: + case *Extract: + case *Field: + case *FieldAddr: + case *Go: + case *Index: + case *IndexAddr: + case *Lookup: + case *MakeChan: + case *MakeClosure: + numFree := len(instr.Fn.(*Function).FreeVars) + numBind := len(instr.Bindings) + if numFree != numBind { + s.errorf("MakeClosure has %d Bindings for function %s with %d free vars", + numBind, instr.Fn, numFree) + + } + if recv := instr.Type().(*types.Signature).Recv(); recv != nil { + s.errorf("MakeClosure's type includes receiver %s", recv.Type()) + } + + case *MakeInterface: + case *MakeMap: + case *MakeSlice: + case *MapUpdate: + case *Next: + case *Range: + case *RunDefers: + case *Select: + case *Send: + case *Slice: + case *Store: + case *TypeAssert: + case *UnOp: + case *DebugRef: + case *BlankStore: + case *Sigma: + // TODO(adonovan): implement checks. + default: + panic(fmt.Sprintf("Unknown instruction type: %T", instr)) + } + + if call, ok := instr.(CallInstruction); ok { + if call.Common().Signature() == nil { + s.errorf("nil signature: %s", call) + } + } + + // Check that value-defining instructions have valid types + // and a valid referrer list. + if v, ok := instr.(Value); ok { + t := v.Type() + if t == nil { + s.errorf("no type: %s = %s", v.Name(), v) + } else if t == tRangeIter { + // not a proper type; ignore. + } else if b, ok := t.Underlying().(*types.Basic); ok && b.Info()&types.IsUntyped != 0 { + s.errorf("instruction has 'untyped' result: %s = %s : %s", v.Name(), v, t) + } + s.checkReferrerList(v) + } + + // Untyped constants are legal as instruction Operands(), + // for example: + // _ = "foo"[0] + // or: + // if wordsize==64 {...} + + // All other non-Instruction Values can be found via their + // enclosing Function or Package. +} + +func (s *sanity) checkFinalInstr(instr Instruction) { + switch instr := instr.(type) { + case *If: + if nsuccs := len(s.block.Succs); nsuccs != 2 { + s.errorf("If-terminated block has %d successors; expected 2", nsuccs) + return + } + if s.block.Succs[0] == s.block.Succs[1] { + s.errorf("If-instruction has same True, False target blocks: %s", s.block.Succs[0]) + return + } + + case *Jump: + if nsuccs := len(s.block.Succs); nsuccs != 1 { + s.errorf("Jump-terminated block has %d successors; expected 1", nsuccs) + return + } + + case *Return: + if nsuccs := len(s.block.Succs); nsuccs != 0 { + s.errorf("Return-terminated block has %d successors; expected none", nsuccs) + return + } + if na, nf := len(instr.Results), s.fn.Signature.Results().Len(); nf != na { + s.errorf("%d-ary return in %d-ary function", na, nf) + } + + case *Panic: + if nsuccs := len(s.block.Succs); nsuccs != 0 { + s.errorf("Panic-terminated block has %d successors; expected none", nsuccs) + return + } + + default: + s.errorf("non-control flow instruction at end of block") + } +} + +func (s *sanity) checkBlock(b *BasicBlock, index int) { + s.block = b + + if b.Index != index { + s.errorf("block has incorrect Index %d", b.Index) + } + if b.parent != s.fn { + s.errorf("block has incorrect parent %s", b.parent) + } + + // Check all blocks are reachable. + // (The entry block is always implicitly reachable, + // as is the Recover block, if any.) + if (index > 0 && b != b.parent.Recover) && len(b.Preds) == 0 { + s.warnf("unreachable block") + if b.Instrs == nil { + // Since this block is about to be pruned, + // tolerating transient problems in it + // simplifies other optimizations. + return + } + } + + // Check predecessor and successor relations are dual, + // and that all blocks in CFG belong to same function. + for _, a := range b.Preds { + found := false + for _, bb := range a.Succs { + if bb == b { + found = true + break + } + } + if !found { + s.errorf("expected successor edge in predecessor %s; found only: %s", a, a.Succs) + } + if a.parent != s.fn { + s.errorf("predecessor %s belongs to different function %s", a, a.parent) + } + } + for _, c := range b.Succs { + found := false + for _, bb := range c.Preds { + if bb == b { + found = true + break + } + } + if !found { + s.errorf("expected predecessor edge in successor %s; found only: %s", c, c.Preds) + } + if c.parent != s.fn { + s.errorf("successor %s belongs to different function %s", c, c.parent) + } + } + + // Check each instruction is sane. + n := len(b.Instrs) + if n == 0 { + s.errorf("basic block contains no instructions") + } + var rands [10]*Value // reuse storage + for j, instr := range b.Instrs { + if instr == nil { + s.errorf("nil instruction at index %d", j) + continue + } + if b2 := instr.Block(); b2 == nil { + s.errorf("nil Block() for instruction at index %d", j) + continue + } else if b2 != b { + s.errorf("wrong Block() (%s) for instruction at index %d ", b2, j) + continue + } + if j < n-1 { + s.checkInstr(j, instr) + } else { + s.checkFinalInstr(instr) + } + + // Check Instruction.Operands. + operands: + for i, op := range instr.Operands(rands[:0]) { + if op == nil { + s.errorf("nil operand pointer %d of %s", i, instr) + continue + } + val := *op + if val == nil { + continue // a nil operand is ok + } + + // Check that "untyped" types only appear on constant operands. + if _, ok := (*op).(*Const); !ok { + if basic, ok := (*op).Type().(*types.Basic); ok { + if basic.Info()&types.IsUntyped != 0 { + s.errorf("operand #%d of %s is untyped: %s", i, instr, basic) + } + } + } + + // Check that Operands that are also Instructions belong to same function. + // TODO(adonovan): also check their block dominates block b. + if val, ok := val.(Instruction); ok { + if val.Block() == nil { + s.errorf("operand %d of %s is an instruction (%s) that belongs to no block", i, instr, val) + } else if val.Parent() != s.fn { + s.errorf("operand %d of %s is an instruction (%s) from function %s", i, instr, val, val.Parent()) + } + } + + // Check that each function-local operand of + // instr refers back to instr. (NB: quadratic) + switch val := val.(type) { + case *Const, *Global, *Builtin: + continue // not local + case *Function: + if val.parent == nil { + continue // only anon functions are local + } + } + + // TODO(adonovan): check val.Parent() != nil <=> val.Referrers() is defined. + + if refs := val.Referrers(); refs != nil { + for _, ref := range *refs { + if ref == instr { + continue operands + } + } + s.errorf("operand %d of %s (%s) does not refer to us", i, instr, val) + } else { + s.errorf("operand %d of %s (%s) has no referrers", i, instr, val) + } + } + } +} + +func (s *sanity) checkReferrerList(v Value) { + refs := v.Referrers() + if refs == nil { + s.errorf("%s has missing referrer list", v.Name()) + return + } + for i, ref := range *refs { + if _, ok := s.instrs[ref]; !ok { + s.errorf("%s.Referrers()[%d] = %s is not an instruction belonging to this function", v.Name(), i, ref) + } + } +} + +func (s *sanity) checkFunction(fn *Function) bool { + // TODO(adonovan): check Function invariants: + // - check params match signature + // - check transient fields are nil + // - warn if any fn.Locals do not appear among block instructions. + s.fn = fn + if fn.Prog == nil { + s.errorf("nil Prog") + } + + fn.String() // must not crash + fn.RelString(fn.pkg()) // must not crash + + // All functions have a package, except delegates (which are + // shared across packages, or duplicated as weak symbols in a + // separate-compilation model), and error.Error. + if fn.Pkg == nil { + if strings.HasPrefix(fn.Synthetic, "wrapper ") || + strings.HasPrefix(fn.Synthetic, "bound ") || + strings.HasPrefix(fn.Synthetic, "thunk ") || + strings.HasSuffix(fn.name, "Error") { + // ok + } else { + s.errorf("nil Pkg") + } + } + if src, syn := fn.Synthetic == "", fn.Syntax() != nil; src != syn { + s.errorf("got fromSource=%t, hasSyntax=%t; want same values", src, syn) + } + for i, l := range fn.Locals { + if l.Parent() != fn { + s.errorf("Local %s at index %d has wrong parent", l.Name(), i) + } + if l.Heap { + s.errorf("Local %s at index %d has Heap flag set", l.Name(), i) + } + } + // Build the set of valid referrers. + s.instrs = make(map[Instruction]struct{}) + for _, b := range fn.Blocks { + for _, instr := range b.Instrs { + s.instrs[instr] = struct{}{} + } + } + for i, p := range fn.Params { + if p.Parent() != fn { + s.errorf("Param %s at index %d has wrong parent", p.Name(), i) + } + s.checkReferrerList(p) + } + for i, fv := range fn.FreeVars { + if fv.Parent() != fn { + s.errorf("FreeVar %s at index %d has wrong parent", fv.Name(), i) + } + s.checkReferrerList(fv) + } + + if fn.Blocks != nil && len(fn.Blocks) == 0 { + // Function _had_ blocks (so it's not external) but + // they were "optimized" away, even the entry block. + s.errorf("Blocks slice is non-nil but empty") + } + for i, b := range fn.Blocks { + if b == nil { + s.warnf("nil *BasicBlock at f.Blocks[%d]", i) + continue + } + s.checkBlock(b, i) + } + if fn.Recover != nil && fn.Blocks[fn.Recover.Index] != fn.Recover { + s.errorf("Recover block is not in Blocks slice") + } + + s.block = nil + for i, anon := range fn.AnonFuncs { + if anon.Parent() != fn { + s.errorf("AnonFuncs[%d]=%s but %s.Parent()=%s", i, anon, anon, anon.Parent()) + } + } + s.fn = nil + return !s.insane +} + +// sanityCheckPackage checks invariants of packages upon creation. +// It does not require that the package is built. +// Unlike sanityCheck (for functions), it just panics at the first error. +func sanityCheckPackage(pkg *Package) { + if pkg.Pkg == nil { + panic(fmt.Sprintf("Package %s has no Object", pkg)) + } + pkg.String() // must not crash + + for name, mem := range pkg.Members { + if name != mem.Name() { + panic(fmt.Sprintf("%s: %T.Name() = %s, want %s", + pkg.Pkg.Path(), mem, mem.Name(), name)) + } + obj := mem.Object() + if obj == nil { + // This check is sound because fields + // {Global,Function}.object have type + // types.Object. (If they were declared as + // *types.{Var,Func}, we'd have a non-empty + // interface containing a nil pointer.) + + continue // not all members have typechecker objects + } + if obj.Name() != name { + if obj.Name() == "init" && strings.HasPrefix(mem.Name(), "init#") { + // Ok. The name of a declared init function varies between + // its types.Func ("init") and its ssa.Function ("init#%d"). + } else { + panic(fmt.Sprintf("%s: %T.Object().Name() = %s, want %s", + pkg.Pkg.Path(), mem, obj.Name(), name)) + } + } + if obj.Pos() != mem.Pos() { + panic(fmt.Sprintf("%s Pos=%d obj.Pos=%d", mem, mem.Pos(), obj.Pos())) + } + } +} diff --git a/vendor/honnef.co/go/tools/ssa/source.go b/vendor/honnef.co/go/tools/ssa/source.go new file mode 100644 index 0000000000..6d2223edaa --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/source.go @@ -0,0 +1,293 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file defines utilities for working with source positions +// or source-level named entities ("objects"). + +// TODO(adonovan): test that {Value,Instruction}.Pos() positions match +// the originating syntax, as specified. + +import ( + "go/ast" + "go/token" + "go/types" +) + +// EnclosingFunction returns the function that contains the syntax +// node denoted by path. +// +// Syntax associated with package-level variable specifications is +// enclosed by the package's init() function. +// +// Returns nil if not found; reasons might include: +// - the node is not enclosed by any function. +// - the node is within an anonymous function (FuncLit) and +// its SSA function has not been created yet +// (pkg.Build() has not yet been called). +// +func EnclosingFunction(pkg *Package, path []ast.Node) *Function { + // Start with package-level function... + fn := findEnclosingPackageLevelFunction(pkg, path) + if fn == nil { + return nil // not in any function + } + + // ...then walk down the nested anonymous functions. + n := len(path) +outer: + for i := range path { + if lit, ok := path[n-1-i].(*ast.FuncLit); ok { + for _, anon := range fn.AnonFuncs { + if anon.Pos() == lit.Type.Func { + fn = anon + continue outer + } + } + // SSA function not found: + // - package not yet built, or maybe + // - builder skipped FuncLit in dead block + // (in principle; but currently the Builder + // generates even dead FuncLits). + return nil + } + } + return fn +} + +// HasEnclosingFunction returns true if the AST node denoted by path +// is contained within the declaration of some function or +// package-level variable. +// +// Unlike EnclosingFunction, the behaviour of this function does not +// depend on whether SSA code for pkg has been built, so it can be +// used to quickly reject check inputs that will cause +// EnclosingFunction to fail, prior to SSA building. +// +func HasEnclosingFunction(pkg *Package, path []ast.Node) bool { + return findEnclosingPackageLevelFunction(pkg, path) != nil +} + +// findEnclosingPackageLevelFunction returns the Function +// corresponding to the package-level function enclosing path. +// +func findEnclosingPackageLevelFunction(pkg *Package, path []ast.Node) *Function { + if n := len(path); n >= 2 { // [... {Gen,Func}Decl File] + switch decl := path[n-2].(type) { + case *ast.GenDecl: + if decl.Tok == token.VAR && n >= 3 { + // Package-level 'var' initializer. + return pkg.init + } + + case *ast.FuncDecl: + if decl.Recv == nil && decl.Name.Name == "init" { + // Explicit init() function. + for _, b := range pkg.init.Blocks { + for _, instr := range b.Instrs { + if instr, ok := instr.(*Call); ok { + if callee, ok := instr.Call.Value.(*Function); ok && callee.Pkg == pkg && callee.Pos() == decl.Name.NamePos { + return callee + } + } + } + } + // Hack: return non-nil when SSA is not yet + // built so that HasEnclosingFunction works. + return pkg.init + } + // Declared function/method. + return findNamedFunc(pkg, decl.Name.NamePos) + } + } + return nil // not in any function +} + +// findNamedFunc returns the named function whose FuncDecl.Ident is at +// position pos. +// +func findNamedFunc(pkg *Package, pos token.Pos) *Function { + // Look at all package members and method sets of named types. + // Not very efficient. + for _, mem := range pkg.Members { + switch mem := mem.(type) { + case *Function: + if mem.Pos() == pos { + return mem + } + case *Type: + mset := pkg.Prog.MethodSets.MethodSet(types.NewPointer(mem.Type())) + for i, n := 0, mset.Len(); i < n; i++ { + // Don't call Program.Method: avoid creating wrappers. + obj := mset.At(i).Obj().(*types.Func) + if obj.Pos() == pos { + return pkg.values[obj].(*Function) + } + } + } + } + return nil +} + +// ValueForExpr returns the SSA Value that corresponds to non-constant +// expression e. +// +// It returns nil if no value was found, e.g. +// - the expression is not lexically contained within f; +// - f was not built with debug information; or +// - e is a constant expression. (For efficiency, no debug +// information is stored for constants. Use +// go/types.Info.Types[e].Value instead.) +// - e is a reference to nil or a built-in function. +// - the value was optimised away. +// +// If e is an addressable expression used in an lvalue context, +// value is the address denoted by e, and isAddr is true. +// +// The types of e (or &e, if isAddr) and the result are equal +// (modulo "untyped" bools resulting from comparisons). +// +// (Tip: to find the ssa.Value given a source position, use +// importer.PathEnclosingInterval to locate the ast.Node, then +// EnclosingFunction to locate the Function, then ValueForExpr to find +// the ssa.Value.) +// +func (f *Function) ValueForExpr(e ast.Expr) (value Value, isAddr bool) { + if f.debugInfo() { // (opt) + e = unparen(e) + for _, b := range f.Blocks { + for _, instr := range b.Instrs { + if ref, ok := instr.(*DebugRef); ok { + if ref.Expr == e { + return ref.X, ref.IsAddr + } + } + } + } + } + return +} + +// --- Lookup functions for source-level named entities (types.Objects) --- + +// Package returns the SSA Package corresponding to the specified +// type-checker package object. +// It returns nil if no such SSA package has been created. +// +func (prog *Program) Package(obj *types.Package) *Package { + return prog.packages[obj] +} + +// packageLevelValue returns the package-level value corresponding to +// the specified named object, which may be a package-level const +// (*Const), var (*Global) or func (*Function) of some package in +// prog. It returns nil if the object is not found. +// +func (prog *Program) packageLevelValue(obj types.Object) Value { + if pkg, ok := prog.packages[obj.Pkg()]; ok { + return pkg.values[obj] + } + return nil +} + +// FuncValue returns the concrete Function denoted by the source-level +// named function obj, or nil if obj denotes an interface method. +// +// TODO(adonovan): check the invariant that obj.Type() matches the +// result's Signature, both in the params/results and in the receiver. +// +func (prog *Program) FuncValue(obj *types.Func) *Function { + fn, _ := prog.packageLevelValue(obj).(*Function) + return fn +} + +// ConstValue returns the SSA Value denoted by the source-level named +// constant obj. +// +func (prog *Program) ConstValue(obj *types.Const) *Const { + // TODO(adonovan): opt: share (don't reallocate) + // Consts for const objects and constant ast.Exprs. + + // Universal constant? {true,false,nil} + if obj.Parent() == types.Universe { + return NewConst(obj.Val(), obj.Type()) + } + // Package-level named constant? + if v := prog.packageLevelValue(obj); v != nil { + return v.(*Const) + } + return NewConst(obj.Val(), obj.Type()) +} + +// VarValue returns the SSA Value that corresponds to a specific +// identifier denoting the source-level named variable obj. +// +// VarValue returns nil if a local variable was not found, perhaps +// because its package was not built, the debug information was not +// requested during SSA construction, or the value was optimized away. +// +// ref is the path to an ast.Ident (e.g. from PathEnclosingInterval), +// and that ident must resolve to obj. +// +// pkg is the package enclosing the reference. (A reference to a var +// always occurs within a function, so we need to know where to find it.) +// +// If the identifier is a field selector and its base expression is +// non-addressable, then VarValue returns the value of that field. +// For example: +// func f() struct {x int} +// f().x // VarValue(x) returns a *Field instruction of type int +// +// All other identifiers denote addressable locations (variables). +// For them, VarValue may return either the variable's address or its +// value, even when the expression is evaluated only for its value; the +// situation is reported by isAddr, the second component of the result. +// +// If !isAddr, the returned value is the one associated with the +// specific identifier. For example, +// var x int // VarValue(x) returns Const 0 here +// x = 1 // VarValue(x) returns Const 1 here +// +// It is not specified whether the value or the address is returned in +// any particular case, as it may depend upon optimizations performed +// during SSA code generation, such as registerization, constant +// folding, avoidance of materialization of subexpressions, etc. +// +func (prog *Program) VarValue(obj *types.Var, pkg *Package, ref []ast.Node) (value Value, isAddr bool) { + // All references to a var are local to some function, possibly init. + fn := EnclosingFunction(pkg, ref) + if fn == nil { + return // e.g. def of struct field; SSA not built? + } + + id := ref[0].(*ast.Ident) + + // Defining ident of a parameter? + if id.Pos() == obj.Pos() { + for _, param := range fn.Params { + if param.Object() == obj { + return param, false + } + } + } + + // Other ident? + for _, b := range fn.Blocks { + for _, instr := range b.Instrs { + if dr, ok := instr.(*DebugRef); ok { + if dr.Pos() == id.Pos() { + return dr.X, dr.IsAddr + } + } + } + } + + // Defining ident of package-level var? + if v := prog.packageLevelValue(obj); v != nil { + return v.(*Global), true + } + + return // e.g. debug info not requested, or var optimized away +} diff --git a/vendor/honnef.co/go/tools/ssa/ssa.go b/vendor/honnef.co/go/tools/ssa/ssa.go new file mode 100644 index 0000000000..8825e7b599 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/ssa.go @@ -0,0 +1,1745 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This package defines a high-level intermediate representation for +// Go programs using static single-assignment (SSA) form. + +import ( + "fmt" + "go/ast" + exact "go/constant" + "go/token" + "go/types" + "sync" + + "golang.org/x/tools/go/types/typeutil" +) + +// A Program is a partial or complete Go program converted to SSA form. +type Program struct { + Fset *token.FileSet // position information for the files of this Program + imported map[string]*Package // all importable Packages, keyed by import path + packages map[*types.Package]*Package // all loaded Packages, keyed by object + mode BuilderMode // set of mode bits for SSA construction + MethodSets typeutil.MethodSetCache // cache of type-checker's method-sets + + methodsMu sync.Mutex // guards the following maps: + methodSets typeutil.Map // maps type to its concrete methodSet + runtimeTypes typeutil.Map // types for which rtypes are needed + canon typeutil.Map // type canonicalization map + bounds map[*types.Func]*Function // bounds for curried x.Method closures + thunks map[selectionKey]*Function // thunks for T.Method expressions +} + +// A Package is a single analyzed Go package containing Members for +// all package-level functions, variables, constants and types it +// declares. These may be accessed directly via Members, or via the +// type-specific accessor methods Func, Type, Var and Const. +// +// Members also contains entries for "init" (the synthetic package +// initializer) and "init#%d", the nth declared init function, +// and unspecified other things too. +// +type Package struct { + Prog *Program // the owning program + Pkg *types.Package // the corresponding go/types.Package + Members map[string]Member // all package members keyed by name (incl. init and init#%d) + values map[types.Object]Value // package members (incl. types and methods), keyed by object + init *Function // Func("init"); the package's init function + debug bool // include full debug info in this package + + // The following fields are set transiently, then cleared + // after building. + buildOnce sync.Once // ensures package building occurs once + ninit int32 // number of init functions + info *types.Info // package type information + files []*ast.File // package ASTs +} + +// A Member is a member of a Go package, implemented by *NamedConst, +// *Global, *Function, or *Type; they are created by package-level +// const, var, func and type declarations respectively. +// +type Member interface { + Name() string // declared name of the package member + String() string // package-qualified name of the package member + RelString(*types.Package) string // like String, but relative refs are unqualified + Object() types.Object // typechecker's object for this member, if any + Pos() token.Pos // position of member's declaration, if known + Type() types.Type // type of the package member + Token() token.Token // token.{VAR,FUNC,CONST,TYPE} + Package() *Package // the containing package +} + +// A Type is a Member of a Package representing a package-level named type. +type Type struct { + object *types.TypeName + pkg *Package +} + +// A NamedConst is a Member of a Package representing a package-level +// named constant. +// +// Pos() returns the position of the declaring ast.ValueSpec.Names[*] +// identifier. +// +// NB: a NamedConst is not a Value; it contains a constant Value, which +// it augments with the name and position of its 'const' declaration. +// +type NamedConst struct { + object *types.Const + Value *Const + pkg *Package +} + +// A Value is an SSA value that can be referenced by an instruction. +type Value interface { + // Name returns the name of this value, and determines how + // this Value appears when used as an operand of an + // Instruction. + // + // This is the same as the source name for Parameters, + // Builtins, Functions, FreeVars, Globals. + // For constants, it is a representation of the constant's value + // and type. For all other Values this is the name of the + // virtual register defined by the instruction. + // + // The name of an SSA Value is not semantically significant, + // and may not even be unique within a function. + Name() string + + // If this value is an Instruction, String returns its + // disassembled form; otherwise it returns unspecified + // human-readable information about the Value, such as its + // kind, name and type. + String() string + + // Type returns the type of this value. Many instructions + // (e.g. IndexAddr) change their behaviour depending on the + // types of their operands. + Type() types.Type + + // Parent returns the function to which this Value belongs. + // It returns nil for named Functions, Builtin, Const and Global. + Parent() *Function + + // Referrers returns the list of instructions that have this + // value as one of their operands; it may contain duplicates + // if an instruction has a repeated operand. + // + // Referrers actually returns a pointer through which the + // caller may perform mutations to the object's state. + // + // Referrers is currently only defined if Parent()!=nil, + // i.e. for the function-local values FreeVar, Parameter, + // Functions (iff anonymous) and all value-defining instructions. + // It returns nil for named Functions, Builtin, Const and Global. + // + // Instruction.Operands contains the inverse of this relation. + Referrers() *[]Instruction + + // Pos returns the location of the AST token most closely + // associated with the operation that gave rise to this value, + // or token.NoPos if it was not explicit in the source. + // + // For each ast.Node type, a particular token is designated as + // the closest location for the expression, e.g. the Lparen + // for an *ast.CallExpr. This permits a compact but + // approximate mapping from Values to source positions for use + // in diagnostic messages, for example. + // + // (Do not use this position to determine which Value + // corresponds to an ast.Expr; use Function.ValueForExpr + // instead. NB: it requires that the function was built with + // debug information.) + Pos() token.Pos +} + +// An Instruction is an SSA instruction that computes a new Value or +// has some effect. +// +// An Instruction that defines a value (e.g. BinOp) also implements +// the Value interface; an Instruction that only has an effect (e.g. Store) +// does not. +// +type Instruction interface { + // String returns the disassembled form of this value. + // + // Examples of Instructions that are Values: + // "x + y" (BinOp) + // "len([])" (Call) + // Note that the name of the Value is not printed. + // + // Examples of Instructions that are not Values: + // "return x" (Return) + // "*y = x" (Store) + // + // (The separation Value.Name() from Value.String() is useful + // for some analyses which distinguish the operation from the + // value it defines, e.g., 'y = local int' is both an allocation + // of memory 'local int' and a definition of a pointer y.) + String() string + + // Parent returns the function to which this instruction + // belongs. + Parent() *Function + + // Block returns the basic block to which this instruction + // belongs. + Block() *BasicBlock + + // setBlock sets the basic block to which this instruction belongs. + setBlock(*BasicBlock) + + // Operands returns the operands of this instruction: the + // set of Values it references. + // + // Specifically, it appends their addresses to rands, a + // user-provided slice, and returns the resulting slice, + // permitting avoidance of memory allocation. + // + // The operands are appended in undefined order, but the order + // is consistent for a given Instruction; the addresses are + // always non-nil but may point to a nil Value. Clients may + // store through the pointers, e.g. to effect a value + // renaming. + // + // Value.Referrers is a subset of the inverse of this + // relation. (Referrers are not tracked for all types of + // Values.) + Operands(rands []*Value) []*Value + + // Pos returns the location of the AST token most closely + // associated with the operation that gave rise to this + // instruction, or token.NoPos if it was not explicit in the + // source. + // + // For each ast.Node type, a particular token is designated as + // the closest location for the expression, e.g. the Go token + // for an *ast.GoStmt. This permits a compact but approximate + // mapping from Instructions to source positions for use in + // diagnostic messages, for example. + // + // (Do not use this position to determine which Instruction + // corresponds to an ast.Expr; see the notes for Value.Pos. + // This position may be used to determine which non-Value + // Instruction corresponds to some ast.Stmts, but not all: If + // and Jump instructions have no Pos(), for example.) + Pos() token.Pos +} + +// A Node is a node in the SSA value graph. Every concrete type that +// implements Node is also either a Value, an Instruction, or both. +// +// Node contains the methods common to Value and Instruction, plus the +// Operands and Referrers methods generalized to return nil for +// non-Instructions and non-Values, respectively. +// +// Node is provided to simplify SSA graph algorithms. Clients should +// use the more specific and informative Value or Instruction +// interfaces where appropriate. +// +type Node interface { + // Common methods: + String() string + Pos() token.Pos + Parent() *Function + + // Partial methods: + Operands(rands []*Value) []*Value // nil for non-Instructions + Referrers() *[]Instruction // nil for non-Values +} + +// Function represents the parameters, results, and code of a function +// or method. +// +// If Blocks is nil, this indicates an external function for which no +// Go source code is available. In this case, FreeVars and Locals +// are nil too. Clients performing whole-program analysis must +// handle external functions specially. +// +// Blocks contains the function's control-flow graph (CFG). +// Blocks[0] is the function entry point; block order is not otherwise +// semantically significant, though it may affect the readability of +// the disassembly. +// To iterate over the blocks in dominance order, use DomPreorder(). +// +// Recover is an optional second entry point to which control resumes +// after a recovered panic. The Recover block may contain only a return +// statement, preceded by a load of the function's named return +// parameters, if any. +// +// A nested function (Parent()!=nil) that refers to one or more +// lexically enclosing local variables ("free variables") has FreeVars. +// Such functions cannot be called directly but require a +// value created by MakeClosure which, via its Bindings, supplies +// values for these parameters. +// +// If the function is a method (Signature.Recv() != nil) then the first +// element of Params is the receiver parameter. +// +// A Go package may declare many functions called "init". +// For each one, Object().Name() returns "init" but Name() returns +// "init#1", etc, in declaration order. +// +// Pos() returns the declaring ast.FuncLit.Type.Func or the position +// of the ast.FuncDecl.Name, if the function was explicit in the +// source. Synthetic wrappers, for which Synthetic != "", may share +// the same position as the function they wrap. +// Syntax.Pos() always returns the position of the declaring "func" token. +// +// Type() returns the function's Signature. +// +type Function struct { + name string + object types.Object // a declared *types.Func or one of its wrappers + method *types.Selection // info about provenance of synthetic methods + Signature *types.Signature + pos token.Pos + + Synthetic string // provenance of synthetic function; "" for true source functions + syntax ast.Node // *ast.Func{Decl,Lit}; replaced with simple ast.Node after build, unless debug mode + parent *Function // enclosing function if anon; nil if global + Pkg *Package // enclosing package; nil for shared funcs (wrappers and error.Error) + Prog *Program // enclosing program + Params []*Parameter // function parameters; for methods, includes receiver + FreeVars []*FreeVar // free variables whose values must be supplied by closure + Locals []*Alloc // local variables of this function + Blocks []*BasicBlock // basic blocks of the function; nil => external + Recover *BasicBlock // optional; control transfers here after recovered panic + AnonFuncs []*Function // anonymous functions directly beneath this one + referrers []Instruction // referring instructions (iff Parent() != nil) + + // The following fields are set transiently during building, + // then cleared. + currentBlock *BasicBlock // where to emit code + objects map[types.Object]Value // addresses of local variables + namedResults []*Alloc // tuple of named results + targets *targets // linked stack of branch targets + lblocks map[*ast.Object]*lblock // labelled blocks +} + +// BasicBlock represents an SSA basic block. +// +// The final element of Instrs is always an explicit transfer of +// control (If, Jump, Return, or Panic). +// +// A block may contain no Instructions only if it is unreachable, +// i.e., Preds is nil. Empty blocks are typically pruned. +// +// BasicBlocks and their Preds/Succs relation form a (possibly cyclic) +// graph independent of the SSA Value graph: the control-flow graph or +// CFG. It is illegal for multiple edges to exist between the same +// pair of blocks. +// +// Each BasicBlock is also a node in the dominator tree of the CFG. +// The tree may be navigated using Idom()/Dominees() and queried using +// Dominates(). +// +// The order of Preds and Succs is significant (to Phi and If +// instructions, respectively). +// +type BasicBlock struct { + Index int // index of this block within Parent().Blocks + Comment string // optional label; no semantic significance + parent *Function // parent function + Instrs []Instruction // instructions in order + Preds, Succs []*BasicBlock // predecessors and successors + succs2 [2]*BasicBlock // initial space for Succs + dom domInfo // dominator tree info + gaps int // number of nil Instrs (transient) + rundefers int // number of rundefers (transient) +} + +// Pure values ---------------------------------------- + +// A FreeVar represents a free variable of the function to which it +// belongs. +// +// FreeVars are used to implement anonymous functions, whose free +// variables are lexically captured in a closure formed by +// MakeClosure. The value of such a free var is an Alloc or another +// FreeVar and is considered a potentially escaping heap address, with +// pointer type. +// +// FreeVars are also used to implement bound method closures. Such a +// free var represents the receiver value and may be of any type that +// has concrete methods. +// +// Pos() returns the position of the value that was captured, which +// belongs to an enclosing function. +// +type FreeVar struct { + name string + typ types.Type + pos token.Pos + parent *Function + referrers []Instruction + + // Transiently needed during building. + outer Value // the Value captured from the enclosing context. +} + +// A Parameter represents an input parameter of a function. +// +type Parameter struct { + name string + object types.Object // a *types.Var; nil for non-source locals + typ types.Type + pos token.Pos + parent *Function + referrers []Instruction +} + +// A Const represents the value of a constant expression. +// +// The underlying type of a constant may be any boolean, numeric, or +// string type. In addition, a Const may represent the nil value of +// any reference type---interface, map, channel, pointer, slice, or +// function---but not "untyped nil". +// +// All source-level constant expressions are represented by a Const +// of the same type and value. +// +// Value holds the exact value of the constant, independent of its +// Type(), using the same representation as package go/exact uses for +// constants, or nil for a typed nil value. +// +// Pos() returns token.NoPos. +// +// Example printed form: +// 42:int +// "hello":untyped string +// 3+4i:MyComplex +// +type Const struct { + typ types.Type + Value exact.Value +} + +// A Global is a named Value holding the address of a package-level +// variable. +// +// Pos() returns the position of the ast.ValueSpec.Names[*] +// identifier. +// +type Global struct { + name string + object types.Object // a *types.Var; may be nil for synthetics e.g. init$guard + typ types.Type + pos token.Pos + + Pkg *Package +} + +// A Builtin represents a specific use of a built-in function, e.g. len. +// +// Builtins are immutable values. Builtins do not have addresses. +// Builtins can only appear in CallCommon.Func. +// +// Name() indicates the function: one of the built-in functions from the +// Go spec (excluding "make" and "new") or one of these ssa-defined +// intrinsics: +// +// // wrapnilchk returns ptr if non-nil, panics otherwise. +// // (For use in indirection wrappers.) +// func ssa:wrapnilchk(ptr *T, recvType, methodName string) *T +// +// Object() returns a *types.Builtin for built-ins defined by the spec, +// nil for others. +// +// Type() returns a *types.Signature representing the effective +// signature of the built-in for this call. +// +type Builtin struct { + name string + sig *types.Signature +} + +// Value-defining instructions ---------------------------------------- + +// The Alloc instruction reserves space for a variable of the given type, +// zero-initializes it, and yields its address. +// +// Alloc values are always addresses, and have pointer types, so the +// type of the allocated variable is actually +// Type().Underlying().(*types.Pointer).Elem(). +// +// If Heap is false, Alloc allocates space in the function's +// activation record (frame); we refer to an Alloc(Heap=false) as a +// "local" alloc. Each local Alloc returns the same address each time +// it is executed within the same activation; the space is +// re-initialized to zero. +// +// If Heap is true, Alloc allocates space in the heap; we +// refer to an Alloc(Heap=true) as a "new" alloc. Each new Alloc +// returns a different address each time it is executed. +// +// When Alloc is applied to a channel, map or slice type, it returns +// the address of an uninitialized (nil) reference of that kind; store +// the result of MakeSlice, MakeMap or MakeChan in that location to +// instantiate these types. +// +// Pos() returns the ast.CompositeLit.Lbrace for a composite literal, +// or the ast.CallExpr.Rparen for a call to new() or for a call that +// allocates a varargs slice. +// +// Example printed form: +// t0 = local int +// t1 = new int +// +type Alloc struct { + register + Comment string + Heap bool + index int // dense numbering; for lifting +} + +var _ Instruction = (*Sigma)(nil) +var _ Value = (*Sigma)(nil) + +type Sigma struct { + register + X Value + Branch bool +} + +func (p *Sigma) Value() Value { + v := p.X + for { + sigma, ok := v.(*Sigma) + if !ok { + break + } + v = sigma + } + return v +} + +func (p *Sigma) String() string { + return fmt.Sprintf("σ [%s.%t]", relName(p.X, p), p.Branch) +} + +// The Phi instruction represents an SSA φ-node, which combines values +// that differ across incoming control-flow edges and yields a new +// value. Within a block, all φ-nodes must appear before all non-φ +// nodes. +// +// Pos() returns the position of the && or || for short-circuit +// control-flow joins, or that of the *Alloc for φ-nodes inserted +// during SSA renaming. +// +// Example printed form: +// t2 = phi [0: t0, 1: t1] +// +type Phi struct { + register + Comment string // a hint as to its purpose + Edges []Value // Edges[i] is value for Block().Preds[i] +} + +// The Call instruction represents a function or method call. +// +// The Call instruction yields the function result if there is exactly +// one. Otherwise it returns a tuple, the components of which are +// accessed via Extract. +// +// See CallCommon for generic function call documentation. +// +// Pos() returns the ast.CallExpr.Lparen, if explicit in the source. +// +// Example printed form: +// t2 = println(t0, t1) +// t4 = t3() +// t7 = invoke t5.Println(...t6) +// +type Call struct { + register + Call CallCommon +} + +// The BinOp instruction yields the result of binary operation X Op Y. +// +// Pos() returns the ast.BinaryExpr.OpPos, if explicit in the source. +// +// Example printed form: +// t1 = t0 + 1:int +// +type BinOp struct { + register + // One of: + // ADD SUB MUL QUO REM + - * / % + // AND OR XOR SHL SHR AND_NOT & | ^ << >> &~ + // EQL LSS GTR NEQ LEQ GEQ == != < <= < >= + Op token.Token + X, Y Value +} + +// The UnOp instruction yields the result of Op X. +// ARROW is channel receive. +// MUL is pointer indirection (load). +// XOR is bitwise complement. +// SUB is negation. +// NOT is logical negation. +// +// If CommaOk and Op=ARROW, the result is a 2-tuple of the value above +// and a boolean indicating the success of the receive. The +// components of the tuple are accessed using Extract. +// +// Pos() returns the ast.UnaryExpr.OpPos, if explicit in the source. +// For receive operations (ARROW) implicit in ranging over a channel, +// Pos() returns the ast.RangeStmt.For. +// For implicit memory loads (STAR), Pos() returns the position of the +// most closely associated source-level construct; the details are not +// specified. +// +// Example printed form: +// t0 = *x +// t2 = <-t1,ok +// +type UnOp struct { + register + Op token.Token // One of: NOT SUB ARROW MUL XOR ! - <- * ^ + X Value + CommaOk bool +} + +// The ChangeType instruction applies to X a value-preserving type +// change to Type(). +// +// Type changes are permitted: +// - between a named type and its underlying type. +// - between two named types of the same underlying type. +// - between (possibly named) pointers to identical base types. +// - from a bidirectional channel to a read- or write-channel, +// optionally adding/removing a name. +// +// This operation cannot fail dynamically. +// +// Pos() returns the ast.CallExpr.Lparen, if the instruction arose +// from an explicit conversion in the source. +// +// Example printed form: +// t1 = changetype *int <- IntPtr (t0) +// +type ChangeType struct { + register + X Value +} + +// The Convert instruction yields the conversion of value X to type +// Type(). One or both of those types is basic (but possibly named). +// +// A conversion may change the value and representation of its operand. +// Conversions are permitted: +// - between real numeric types. +// - between complex numeric types. +// - between string and []byte or []rune. +// - between pointers and unsafe.Pointer. +// - between unsafe.Pointer and uintptr. +// - from (Unicode) integer to (UTF-8) string. +// A conversion may imply a type name change also. +// +// This operation cannot fail dynamically. +// +// Conversions of untyped string/number/bool constants to a specific +// representation are eliminated during SSA construction. +// +// Pos() returns the ast.CallExpr.Lparen, if the instruction arose +// from an explicit conversion in the source. +// +// Example printed form: +// t1 = convert []byte <- string (t0) +// +type Convert struct { + register + X Value +} + +// ChangeInterface constructs a value of one interface type from a +// value of another interface type known to be assignable to it. +// This operation cannot fail. +// +// Pos() returns the ast.CallExpr.Lparen if the instruction arose from +// an explicit T(e) conversion; the ast.TypeAssertExpr.Lparen if the +// instruction arose from an explicit e.(T) operation; or token.NoPos +// otherwise. +// +// Example printed form: +// t1 = change interface interface{} <- I (t0) +// +type ChangeInterface struct { + register + X Value +} + +// MakeInterface constructs an instance of an interface type from a +// value of a concrete type. +// +// Use Program.MethodSets.MethodSet(X.Type()) to find the method-set +// of X, and Program.Method(m) to find the implementation of a method. +// +// To construct the zero value of an interface type T, use: +// NewConst(exact.MakeNil(), T, pos) +// +// Pos() returns the ast.CallExpr.Lparen, if the instruction arose +// from an explicit conversion in the source. +// +// Example printed form: +// t1 = make interface{} <- int (42:int) +// t2 = make Stringer <- t0 +// +type MakeInterface struct { + register + X Value +} + +// The MakeClosure instruction yields a closure value whose code is +// Fn and whose free variables' values are supplied by Bindings. +// +// Type() returns a (possibly named) *types.Signature. +// +// Pos() returns the ast.FuncLit.Type.Func for a function literal +// closure or the ast.SelectorExpr.Sel for a bound method closure. +// +// Example printed form: +// t0 = make closure anon@1.2 [x y z] +// t1 = make closure bound$(main.I).add [i] +// +type MakeClosure struct { + register + Fn Value // always a *Function + Bindings []Value // values for each free variable in Fn.FreeVars +} + +// The MakeMap instruction creates a new hash-table-based map object +// and yields a value of kind map. +// +// Type() returns a (possibly named) *types.Map. +// +// Pos() returns the ast.CallExpr.Lparen, if created by make(map), or +// the ast.CompositeLit.Lbrack if created by a literal. +// +// Example printed form: +// t1 = make map[string]int t0 +// t1 = make StringIntMap t0 +// +type MakeMap struct { + register + Reserve Value // initial space reservation; nil => default +} + +// The MakeChan instruction creates a new channel object and yields a +// value of kind chan. +// +// Type() returns a (possibly named) *types.Chan. +// +// Pos() returns the ast.CallExpr.Lparen for the make(chan) that +// created it. +// +// Example printed form: +// t0 = make chan int 0 +// t0 = make IntChan 0 +// +type MakeChan struct { + register + Size Value // int; size of buffer; zero => synchronous. +} + +// The MakeSlice instruction yields a slice of length Len backed by a +// newly allocated array of length Cap. +// +// Both Len and Cap must be non-nil Values of integer type. +// +// (Alloc(types.Array) followed by Slice will not suffice because +// Alloc can only create arrays of constant length.) +// +// Type() returns a (possibly named) *types.Slice. +// +// Pos() returns the ast.CallExpr.Lparen for the make([]T) that +// created it. +// +// Example printed form: +// t1 = make []string 1:int t0 +// t1 = make StringSlice 1:int t0 +// +type MakeSlice struct { + register + Len Value + Cap Value +} + +// The Slice instruction yields a slice of an existing string, slice +// or *array X between optional integer bounds Low and High. +// +// Dynamically, this instruction panics if X evaluates to a nil *array +// pointer. +// +// Type() returns string if the type of X was string, otherwise a +// *types.Slice with the same element type as X. +// +// Pos() returns the ast.SliceExpr.Lbrack if created by a x[:] slice +// operation, the ast.CompositeLit.Lbrace if created by a literal, or +// NoPos if not explicit in the source (e.g. a variadic argument slice). +// +// Example printed form: +// t1 = slice t0[1:] +// +type Slice struct { + register + X Value // slice, string, or *array + Low, High, Max Value // each may be nil +} + +// The FieldAddr instruction yields the address of Field of *struct X. +// +// The field is identified by its index within the field list of the +// struct type of X. +// +// Dynamically, this instruction panics if X evaluates to a nil +// pointer. +// +// Type() returns a (possibly named) *types.Pointer. +// +// Pos() returns the position of the ast.SelectorExpr.Sel for the +// field, if explicit in the source. +// +// Example printed form: +// t1 = &t0.name [#1] +// +type FieldAddr struct { + register + X Value // *struct + Field int // index into X.Type().Deref().(*types.Struct).Fields +} + +// The Field instruction yields the Field of struct X. +// +// The field is identified by its index within the field list of the +// struct type of X; by using numeric indices we avoid ambiguity of +// package-local identifiers and permit compact representations. +// +// Pos() returns the position of the ast.SelectorExpr.Sel for the +// field, if explicit in the source. +// +// Example printed form: +// t1 = t0.name [#1] +// +type Field struct { + register + X Value // struct + Field int // index into X.Type().(*types.Struct).Fields +} + +// The IndexAddr instruction yields the address of the element at +// index Index of collection X. Index is an integer expression. +// +// The elements of maps and strings are not addressable; use Lookup or +// MapUpdate instead. +// +// Dynamically, this instruction panics if X evaluates to a nil *array +// pointer. +// +// Type() returns a (possibly named) *types.Pointer. +// +// Pos() returns the ast.IndexExpr.Lbrack for the index operation, if +// explicit in the source. +// +// Example printed form: +// t2 = &t0[t1] +// +type IndexAddr struct { + register + X Value // slice or *array, + Index Value // numeric index +} + +// The Index instruction yields element Index of array X. +// +// Pos() returns the ast.IndexExpr.Lbrack for the index operation, if +// explicit in the source. +// +// Example printed form: +// t2 = t0[t1] +// +type Index struct { + register + X Value // array + Index Value // integer index +} + +// The Lookup instruction yields element Index of collection X, a map +// or string. Index is an integer expression if X is a string or the +// appropriate key type if X is a map. +// +// If CommaOk, the result is a 2-tuple of the value above and a +// boolean indicating the result of a map membership test for the key. +// The components of the tuple are accessed using Extract. +// +// Pos() returns the ast.IndexExpr.Lbrack, if explicit in the source. +// +// Example printed form: +// t2 = t0[t1] +// t5 = t3[t4],ok +// +type Lookup struct { + register + X Value // string or map + Index Value // numeric or key-typed index + CommaOk bool // return a value,ok pair +} + +// SelectState is a helper for Select. +// It represents one goal state and its corresponding communication. +// +type SelectState struct { + Dir types.ChanDir // direction of case (SendOnly or RecvOnly) + Chan Value // channel to use (for send or receive) + Send Value // value to send (for send) + Pos token.Pos // position of token.ARROW + DebugNode ast.Node // ast.SendStmt or ast.UnaryExpr(<-) [debug mode] +} + +// The Select instruction tests whether (or blocks until) one +// of the specified sent or received states is entered. +// +// Let n be the number of States for which Dir==RECV and T_i (0<=i string iterator; false => map iterator. +} + +// The TypeAssert instruction tests whether interface value X has type +// AssertedType. +// +// If !CommaOk, on success it returns v, the result of the conversion +// (defined below); on failure it panics. +// +// If CommaOk: on success it returns a pair (v, true) where v is the +// result of the conversion; on failure it returns (z, false) where z +// is AssertedType's zero value. The components of the pair must be +// accessed using the Extract instruction. +// +// If AssertedType is a concrete type, TypeAssert checks whether the +// dynamic type in interface X is equal to it, and if so, the result +// of the conversion is a copy of the value in the interface. +// +// If AssertedType is an interface, TypeAssert checks whether the +// dynamic type of the interface is assignable to it, and if so, the +// result of the conversion is a copy of the interface value X. +// If AssertedType is a superinterface of X.Type(), the operation will +// fail iff the operand is nil. (Contrast with ChangeInterface, which +// performs no nil-check.) +// +// Type() reflects the actual type of the result, possibly a +// 2-types.Tuple; AssertedType is the asserted type. +// +// Pos() returns the ast.CallExpr.Lparen if the instruction arose from +// an explicit T(e) conversion; the ast.TypeAssertExpr.Lparen if the +// instruction arose from an explicit e.(T) operation; or the +// ast.CaseClause.Case if the instruction arose from a case of a +// type-switch statement. +// +// Example printed form: +// t1 = typeassert t0.(int) +// t3 = typeassert,ok t2.(T) +// +type TypeAssert struct { + register + X Value + AssertedType types.Type + CommaOk bool +} + +// The Extract instruction yields component Index of Tuple. +// +// This is used to access the results of instructions with multiple +// return values, such as Call, TypeAssert, Next, UnOp(ARROW) and +// IndexExpr(Map). +// +// Example printed form: +// t1 = extract t0 #1 +// +type Extract struct { + register + Tuple Value + Index int +} + +// Instructions executed for effect. They do not yield a value. -------------------- + +// The Jump instruction transfers control to the sole successor of its +// owning block. +// +// A Jump must be the last instruction of its containing BasicBlock. +// +// Pos() returns NoPos. +// +// Example printed form: +// jump done +// +type Jump struct { + anInstruction +} + +// The If instruction transfers control to one of the two successors +// of its owning block, depending on the boolean Cond: the first if +// true, the second if false. +// +// An If instruction must be the last instruction of its containing +// BasicBlock. +// +// Pos() returns NoPos. +// +// Example printed form: +// if t0 goto done else body +// +type If struct { + anInstruction + Cond Value +} + +// The Return instruction returns values and control back to the calling +// function. +// +// len(Results) is always equal to the number of results in the +// function's signature. +// +// If len(Results) > 1, Return returns a tuple value with the specified +// components which the caller must access using Extract instructions. +// +// There is no instruction to return a ready-made tuple like those +// returned by a "value,ok"-mode TypeAssert, Lookup or UnOp(ARROW) or +// a tail-call to a function with multiple result parameters. +// +// Return must be the last instruction of its containing BasicBlock. +// Such a block has no successors. +// +// Pos() returns the ast.ReturnStmt.Return, if explicit in the source. +// +// Example printed form: +// return +// return nil:I, 2:int +// +type Return struct { + anInstruction + Results []Value + pos token.Pos +} + +// The RunDefers instruction pops and invokes the entire stack of +// procedure calls pushed by Defer instructions in this function. +// +// It is legal to encounter multiple 'rundefers' instructions in a +// single control-flow path through a function; this is useful in +// the combined init() function, for example. +// +// Pos() returns NoPos. +// +// Example printed form: +// rundefers +// +type RunDefers struct { + anInstruction +} + +// The Panic instruction initiates a panic with value X. +// +// A Panic instruction must be the last instruction of its containing +// BasicBlock, which must have no successors. +// +// NB: 'go panic(x)' and 'defer panic(x)' do not use this instruction; +// they are treated as calls to a built-in function. +// +// Pos() returns the ast.CallExpr.Lparen if this panic was explicit +// in the source. +// +// Example printed form: +// panic t0 +// +type Panic struct { + anInstruction + X Value // an interface{} + pos token.Pos +} + +// The Go instruction creates a new goroutine and calls the specified +// function within it. +// +// See CallCommon for generic function call documentation. +// +// Pos() returns the ast.GoStmt.Go. +// +// Example printed form: +// go println(t0, t1) +// go t3() +// go invoke t5.Println(...t6) +// +type Go struct { + anInstruction + Call CallCommon + pos token.Pos +} + +// The Defer instruction pushes the specified call onto a stack of +// functions to be called by a RunDefers instruction or by a panic. +// +// See CallCommon for generic function call documentation. +// +// Pos() returns the ast.DeferStmt.Defer. +// +// Example printed form: +// defer println(t0, t1) +// defer t3() +// defer invoke t5.Println(...t6) +// +type Defer struct { + anInstruction + Call CallCommon + pos token.Pos +} + +// The Send instruction sends X on channel Chan. +// +// Pos() returns the ast.SendStmt.Arrow, if explicit in the source. +// +// Example printed form: +// send t0 <- t1 +// +type Send struct { + anInstruction + Chan, X Value + pos token.Pos +} + +// The Store instruction stores Val at address Addr. +// Stores can be of arbitrary types. +// +// Pos() returns the position of the source-level construct most closely +// associated with the memory store operation. +// Since implicit memory stores are numerous and varied and depend upon +// implementation choices, the details are not specified. +// +// Example printed form: +// *x = y +// +type Store struct { + anInstruction + Addr Value + Val Value + pos token.Pos +} + +// The BlankStore instruction is emitted for assignments to the blank +// identifier. +// +// BlankStore is a pseudo-instruction: it has no dynamic effect. +// +// Pos() returns NoPos. +// +// Example printed form: +// _ = t0 +// +type BlankStore struct { + anInstruction + Val Value +} + +// The MapUpdate instruction updates the association of Map[Key] to +// Value. +// +// Pos() returns the ast.KeyValueExpr.Colon or ast.IndexExpr.Lbrack, +// if explicit in the source. +// +// Example printed form: +// t0[t1] = t2 +// +type MapUpdate struct { + anInstruction + Map Value + Key Value + Value Value + pos token.Pos +} + +// A DebugRef instruction maps a source-level expression Expr to the +// SSA value X that represents the value (!IsAddr) or address (IsAddr) +// of that expression. +// +// DebugRef is a pseudo-instruction: it has no dynamic effect. +// +// Pos() returns Expr.Pos(), the start position of the source-level +// expression. This is not the same as the "designated" token as +// documented at Value.Pos(). e.g. CallExpr.Pos() does not return the +// position of the ("designated") Lparen token. +// +// If Expr is an *ast.Ident denoting a var or func, Object() returns +// the object; though this information can be obtained from the type +// checker, including it here greatly facilitates debugging. +// For non-Ident expressions, Object() returns nil. +// +// DebugRefs are generated only for functions built with debugging +// enabled; see Package.SetDebugMode() and the GlobalDebug builder +// mode flag. +// +// DebugRefs are not emitted for ast.Idents referring to constants or +// predeclared identifiers, since they are trivial and numerous. +// Nor are they emitted for ast.ParenExprs. +// +// (By representing these as instructions, rather than out-of-band, +// consistency is maintained during transformation passes by the +// ordinary SSA renaming machinery.) +// +// Example printed form: +// ; *ast.CallExpr @ 102:9 is t5 +// ; var x float64 @ 109:72 is x +// ; address of *ast.CompositeLit @ 216:10 is t0 +// +type DebugRef struct { + anInstruction + Expr ast.Expr // the referring expression (never *ast.ParenExpr) + object types.Object // the identity of the source var/func + IsAddr bool // Expr is addressable and X is the address it denotes + X Value // the value or address of Expr +} + +// Embeddable mix-ins and helpers for common parts of other structs. ----------- + +// register is a mix-in embedded by all SSA values that are also +// instructions, i.e. virtual registers, and provides a uniform +// implementation of most of the Value interface: Value.Name() is a +// numbered register (e.g. "t0"); the other methods are field accessors. +// +// Temporary names are automatically assigned to each register on +// completion of building a function in SSA form. +// +// Clients must not assume that the 'id' value (and the Name() derived +// from it) is unique within a function. As always in this API, +// semantics are determined only by identity; names exist only to +// facilitate debugging. +// +type register struct { + anInstruction + num int // "name" of virtual register, e.g. "t0". Not guaranteed unique. + typ types.Type // type of virtual register + pos token.Pos // position of source expression, or NoPos + referrers []Instruction +} + +// anInstruction is a mix-in embedded by all Instructions. +// It provides the implementations of the Block and setBlock methods. +type anInstruction struct { + block *BasicBlock // the basic block of this instruction +} + +// CallCommon is contained by Go, Defer and Call to hold the +// common parts of a function or method call. +// +// Each CallCommon exists in one of two modes, function call and +// interface method invocation, or "call" and "invoke" for short. +// +// 1. "call" mode: when Method is nil (!IsInvoke), a CallCommon +// represents an ordinary function call of the value in Value, +// which may be a *Builtin, a *Function or any other value of kind +// 'func'. +// +// Value may be one of: +// (a) a *Function, indicating a statically dispatched call +// to a package-level function, an anonymous function, or +// a method of a named type. +// (b) a *MakeClosure, indicating an immediately applied +// function literal with free variables. +// (c) a *Builtin, indicating a statically dispatched call +// to a built-in function. +// (d) any other value, indicating a dynamically dispatched +// function call. +// StaticCallee returns the identity of the callee in cases +// (a) and (b), nil otherwise. +// +// Args contains the arguments to the call. If Value is a method, +// Args[0] contains the receiver parameter. +// +// Example printed form: +// t2 = println(t0, t1) +// go t3() +// defer t5(...t6) +// +// 2. "invoke" mode: when Method is non-nil (IsInvoke), a CallCommon +// represents a dynamically dispatched call to an interface method. +// In this mode, Value is the interface value and Method is the +// interface's abstract method. Note: an abstract method may be +// shared by multiple interfaces due to embedding; Value.Type() +// provides the specific interface used for this call. +// +// Value is implicitly supplied to the concrete method implementation +// as the receiver parameter; in other words, Args[0] holds not the +// receiver but the first true argument. +// +// Example printed form: +// t1 = invoke t0.String() +// go invoke t3.Run(t2) +// defer invoke t4.Handle(...t5) +// +// For all calls to variadic functions (Signature().Variadic()), +// the last element of Args is a slice. +// +type CallCommon struct { + Value Value // receiver (invoke mode) or func value (call mode) + Method *types.Func // abstract method (invoke mode) + Args []Value // actual parameters (in static method call, includes receiver) + pos token.Pos // position of CallExpr.Lparen, iff explicit in source +} + +// IsInvoke returns true if this call has "invoke" (not "call") mode. +func (c *CallCommon) IsInvoke() bool { + return c.Method != nil +} + +func (c *CallCommon) Pos() token.Pos { return c.pos } + +// Signature returns the signature of the called function. +// +// For an "invoke"-mode call, the signature of the interface method is +// returned. +// +// In either "call" or "invoke" mode, if the callee is a method, its +// receiver is represented by sig.Recv, not sig.Params().At(0). +// +func (c *CallCommon) Signature() *types.Signature { + if c.Method != nil { + return c.Method.Type().(*types.Signature) + } + return c.Value.Type().Underlying().(*types.Signature) +} + +// StaticCallee returns the callee if this is a trivially static +// "call"-mode call to a function. +func (c *CallCommon) StaticCallee() *Function { + switch fn := c.Value.(type) { + case *Function: + return fn + case *MakeClosure: + return fn.Fn.(*Function) + } + return nil +} + +// Description returns a description of the mode of this call suitable +// for a user interface, e.g., "static method call". +func (c *CallCommon) Description() string { + switch fn := c.Value.(type) { + case *Builtin: + return "built-in function call" + case *MakeClosure: + return "static function closure call" + case *Function: + if fn.Signature.Recv() != nil { + return "static method call" + } + return "static function call" + } + if c.IsInvoke() { + return "dynamic method call" // ("invoke" mode) + } + return "dynamic function call" +} + +// The CallInstruction interface, implemented by *Go, *Defer and *Call, +// exposes the common parts of function-calling instructions, +// yet provides a way back to the Value defined by *Call alone. +// +type CallInstruction interface { + Instruction + Common() *CallCommon // returns the common parts of the call + Value() *Call // returns the result value of the call (*Call) or nil (*Go, *Defer) +} + +func (s *Call) Common() *CallCommon { return &s.Call } +func (s *Defer) Common() *CallCommon { return &s.Call } +func (s *Go) Common() *CallCommon { return &s.Call } + +func (s *Call) Value() *Call { return s } +func (s *Defer) Value() *Call { return nil } +func (s *Go) Value() *Call { return nil } + +func (v *Builtin) Type() types.Type { return v.sig } +func (v *Builtin) Name() string { return v.name } +func (*Builtin) Referrers() *[]Instruction { return nil } +func (v *Builtin) Pos() token.Pos { return token.NoPos } +func (v *Builtin) Object() types.Object { return types.Universe.Lookup(v.name) } +func (v *Builtin) Parent() *Function { return nil } + +func (v *FreeVar) Type() types.Type { return v.typ } +func (v *FreeVar) Name() string { return v.name } +func (v *FreeVar) Referrers() *[]Instruction { return &v.referrers } +func (v *FreeVar) Pos() token.Pos { return v.pos } +func (v *FreeVar) Parent() *Function { return v.parent } + +func (v *Global) Type() types.Type { return v.typ } +func (v *Global) Name() string { return v.name } +func (v *Global) Parent() *Function { return nil } +func (v *Global) Pos() token.Pos { return v.pos } +func (v *Global) Referrers() *[]Instruction { return nil } +func (v *Global) Token() token.Token { return token.VAR } +func (v *Global) Object() types.Object { return v.object } +func (v *Global) String() string { return v.RelString(nil) } +func (v *Global) Package() *Package { return v.Pkg } +func (v *Global) RelString(from *types.Package) string { return relString(v, from) } + +func (v *Function) Name() string { return v.name } +func (v *Function) Type() types.Type { return v.Signature } +func (v *Function) Pos() token.Pos { return v.pos } +func (v *Function) Token() token.Token { return token.FUNC } +func (v *Function) Object() types.Object { return v.object } +func (v *Function) String() string { return v.RelString(nil) } +func (v *Function) Package() *Package { return v.Pkg } +func (v *Function) Parent() *Function { return v.parent } +func (v *Function) Referrers() *[]Instruction { + if v.parent != nil { + return &v.referrers + } + return nil +} + +func (v *Parameter) Type() types.Type { return v.typ } +func (v *Parameter) Name() string { return v.name } +func (v *Parameter) Object() types.Object { return v.object } +func (v *Parameter) Referrers() *[]Instruction { return &v.referrers } +func (v *Parameter) Pos() token.Pos { return v.pos } +func (v *Parameter) Parent() *Function { return v.parent } + +func (v *Alloc) Type() types.Type { return v.typ } +func (v *Alloc) Referrers() *[]Instruction { return &v.referrers } +func (v *Alloc) Pos() token.Pos { return v.pos } + +func (v *register) Type() types.Type { return v.typ } +func (v *register) setType(typ types.Type) { v.typ = typ } +func (v *register) Name() string { return fmt.Sprintf("t%d", v.num) } +func (v *register) setNum(num int) { v.num = num } +func (v *register) Referrers() *[]Instruction { return &v.referrers } +func (v *register) Pos() token.Pos { return v.pos } +func (v *register) setPos(pos token.Pos) { v.pos = pos } + +func (v *anInstruction) Parent() *Function { return v.block.parent } +func (v *anInstruction) Block() *BasicBlock { return v.block } +func (v *anInstruction) setBlock(block *BasicBlock) { v.block = block } +func (v *anInstruction) Referrers() *[]Instruction { return nil } + +func (t *Type) Name() string { return t.object.Name() } +func (t *Type) Pos() token.Pos { return t.object.Pos() } +func (t *Type) Type() types.Type { return t.object.Type() } +func (t *Type) Token() token.Token { return token.TYPE } +func (t *Type) Object() types.Object { return t.object } +func (t *Type) String() string { return t.RelString(nil) } +func (t *Type) Package() *Package { return t.pkg } +func (t *Type) RelString(from *types.Package) string { return relString(t, from) } + +func (c *NamedConst) Name() string { return c.object.Name() } +func (c *NamedConst) Pos() token.Pos { return c.object.Pos() } +func (c *NamedConst) String() string { return c.RelString(nil) } +func (c *NamedConst) Type() types.Type { return c.object.Type() } +func (c *NamedConst) Token() token.Token { return token.CONST } +func (c *NamedConst) Object() types.Object { return c.object } +func (c *NamedConst) Package() *Package { return c.pkg } +func (c *NamedConst) RelString(from *types.Package) string { return relString(c, from) } + +// Func returns the package-level function of the specified name, +// or nil if not found. +// +func (p *Package) Func(name string) (f *Function) { + f, _ = p.Members[name].(*Function) + return +} + +// Var returns the package-level variable of the specified name, +// or nil if not found. +// +func (p *Package) Var(name string) (g *Global) { + g, _ = p.Members[name].(*Global) + return +} + +// Const returns the package-level constant of the specified name, +// or nil if not found. +// +func (p *Package) Const(name string) (c *NamedConst) { + c, _ = p.Members[name].(*NamedConst) + return +} + +// Type returns the package-level type of the specified name, +// or nil if not found. +// +func (p *Package) Type(name string) (t *Type) { + t, _ = p.Members[name].(*Type) + return +} + +func (v *Call) Pos() token.Pos { return v.Call.pos } +func (s *Defer) Pos() token.Pos { return s.pos } +func (s *Go) Pos() token.Pos { return s.pos } +func (s *MapUpdate) Pos() token.Pos { return s.pos } +func (s *Panic) Pos() token.Pos { return s.pos } +func (s *Return) Pos() token.Pos { return s.pos } +func (s *Send) Pos() token.Pos { return s.pos } +func (s *Store) Pos() token.Pos { return s.pos } +func (s *BlankStore) Pos() token.Pos { return token.NoPos } +func (s *If) Pos() token.Pos { return token.NoPos } +func (s *Jump) Pos() token.Pos { return token.NoPos } +func (s *RunDefers) Pos() token.Pos { return token.NoPos } +func (s *DebugRef) Pos() token.Pos { return s.Expr.Pos() } + +// Operands. + +func (v *Alloc) Operands(rands []*Value) []*Value { + return rands +} + +func (v *BinOp) Operands(rands []*Value) []*Value { + return append(rands, &v.X, &v.Y) +} + +func (c *CallCommon) Operands(rands []*Value) []*Value { + rands = append(rands, &c.Value) + for i := range c.Args { + rands = append(rands, &c.Args[i]) + } + return rands +} + +func (s *Go) Operands(rands []*Value) []*Value { + return s.Call.Operands(rands) +} + +func (s *Call) Operands(rands []*Value) []*Value { + return s.Call.Operands(rands) +} + +func (s *Defer) Operands(rands []*Value) []*Value { + return s.Call.Operands(rands) +} + +func (v *ChangeInterface) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +func (v *ChangeType) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +func (v *Convert) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +func (s *DebugRef) Operands(rands []*Value) []*Value { + return append(rands, &s.X) +} + +func (v *Extract) Operands(rands []*Value) []*Value { + return append(rands, &v.Tuple) +} + +func (v *Field) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +func (v *FieldAddr) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +func (s *If) Operands(rands []*Value) []*Value { + return append(rands, &s.Cond) +} + +func (v *Index) Operands(rands []*Value) []*Value { + return append(rands, &v.X, &v.Index) +} + +func (v *IndexAddr) Operands(rands []*Value) []*Value { + return append(rands, &v.X, &v.Index) +} + +func (*Jump) Operands(rands []*Value) []*Value { + return rands +} + +func (v *Lookup) Operands(rands []*Value) []*Value { + return append(rands, &v.X, &v.Index) +} + +func (v *MakeChan) Operands(rands []*Value) []*Value { + return append(rands, &v.Size) +} + +func (v *MakeClosure) Operands(rands []*Value) []*Value { + rands = append(rands, &v.Fn) + for i := range v.Bindings { + rands = append(rands, &v.Bindings[i]) + } + return rands +} + +func (v *MakeInterface) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +func (v *MakeMap) Operands(rands []*Value) []*Value { + return append(rands, &v.Reserve) +} + +func (v *MakeSlice) Operands(rands []*Value) []*Value { + return append(rands, &v.Len, &v.Cap) +} + +func (v *MapUpdate) Operands(rands []*Value) []*Value { + return append(rands, &v.Map, &v.Key, &v.Value) +} + +func (v *Next) Operands(rands []*Value) []*Value { + return append(rands, &v.Iter) +} + +func (s *Panic) Operands(rands []*Value) []*Value { + return append(rands, &s.X) +} + +func (v *Sigma) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +func (v *Phi) Operands(rands []*Value) []*Value { + for i := range v.Edges { + rands = append(rands, &v.Edges[i]) + } + return rands +} + +func (v *Range) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +func (s *Return) Operands(rands []*Value) []*Value { + for i := range s.Results { + rands = append(rands, &s.Results[i]) + } + return rands +} + +func (*RunDefers) Operands(rands []*Value) []*Value { + return rands +} + +func (v *Select) Operands(rands []*Value) []*Value { + for i := range v.States { + rands = append(rands, &v.States[i].Chan, &v.States[i].Send) + } + return rands +} + +func (s *Send) Operands(rands []*Value) []*Value { + return append(rands, &s.Chan, &s.X) +} + +func (v *Slice) Operands(rands []*Value) []*Value { + return append(rands, &v.X, &v.Low, &v.High, &v.Max) +} + +func (s *Store) Operands(rands []*Value) []*Value { + return append(rands, &s.Addr, &s.Val) +} + +func (s *BlankStore) Operands(rands []*Value) []*Value { + return append(rands, &s.Val) +} + +func (v *TypeAssert) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +func (v *UnOp) Operands(rands []*Value) []*Value { + return append(rands, &v.X) +} + +// Non-Instruction Values: +func (v *Builtin) Operands(rands []*Value) []*Value { return rands } +func (v *FreeVar) Operands(rands []*Value) []*Value { return rands } +func (v *Const) Operands(rands []*Value) []*Value { return rands } +func (v *Function) Operands(rands []*Value) []*Value { return rands } +func (v *Global) Operands(rands []*Value) []*Value { return rands } +func (v *Parameter) Operands(rands []*Value) []*Value { return rands } diff --git a/vendor/honnef.co/go/tools/ssa/ssautil/load.go b/vendor/honnef.co/go/tools/ssa/ssautil/load.go new file mode 100644 index 0000000000..3b8694a13d --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/ssautil/load.go @@ -0,0 +1,143 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssautil + +// This file defines utility functions for constructing programs in SSA form. + +import ( + "go/ast" + "go/token" + "go/types" + + "golang.org/x/tools/go/loader" + "golang.org/x/tools/go/packages" + "honnef.co/go/tools/ssa" +) + +// Packages creates an SSA program for a set of packages loaded from +// source syntax using the golang.org/x/tools/go/packages.Load function. +// It creates and returns an SSA package for each well-typed package in +// the initial list. The resulting list of packages has the same length +// as initial, and contains a nil if SSA could not be constructed for +// the corresponding initial package. +// +// Code for bodies of functions is not built until Build is called +// on the resulting Program. +// +// The mode parameter controls diagnostics and checking during SSA construction. +// +func Packages(initial []*packages.Package, mode ssa.BuilderMode) (*ssa.Program, []*ssa.Package) { + var fset *token.FileSet + if len(initial) > 0 { + fset = initial[0].Fset + } + + prog := ssa.NewProgram(fset, mode) + seen := make(map[*packages.Package]*ssa.Package) + var create func(p *packages.Package) *ssa.Package + create = func(p *packages.Package) *ssa.Package { + ssapkg, ok := seen[p] + if !ok { + if p.Types == nil || p.IllTyped { + // not well typed + seen[p] = nil + return nil + } + + ssapkg = prog.CreatePackage(p.Types, p.Syntax, p.TypesInfo, true) + seen[p] = ssapkg + + for _, imp := range p.Imports { + create(imp) + } + } + return ssapkg + } + + var ssapkgs []*ssa.Package + for _, p := range initial { + ssapkgs = append(ssapkgs, create(p)) + } + return prog, ssapkgs +} + +// CreateProgram returns a new program in SSA form, given a program +// loaded from source. An SSA package is created for each transitively +// error-free package of lprog. +// +// Code for bodies of functions is not built until Build is called +// on the result. +// +// mode controls diagnostics and checking during SSA construction. +// +func CreateProgram(lprog *loader.Program, mode ssa.BuilderMode) *ssa.Program { + prog := ssa.NewProgram(lprog.Fset, mode) + + for _, info := range lprog.AllPackages { + if info.TransitivelyErrorFree { + prog.CreatePackage(info.Pkg, info.Files, &info.Info, info.Importable) + } + } + + return prog +} + +// BuildPackage builds an SSA program with IR for a single package. +// +// It populates pkg by type-checking the specified file ASTs. All +// dependencies are loaded using the importer specified by tc, which +// typically loads compiler export data; SSA code cannot be built for +// those packages. BuildPackage then constructs an ssa.Program with all +// dependency packages created, and builds and returns the SSA package +// corresponding to pkg. +// +// The caller must have set pkg.Path() to the import path. +// +// The operation fails if there were any type-checking or import errors. +// +// See ../ssa/example_test.go for an example. +// +func BuildPackage(tc *types.Config, fset *token.FileSet, pkg *types.Package, files []*ast.File, mode ssa.BuilderMode) (*ssa.Package, *types.Info, error) { + if fset == nil { + panic("no token.FileSet") + } + if pkg.Path() == "" { + panic("package has no import path") + } + + info := &types.Info{ + Types: make(map[ast.Expr]types.TypeAndValue), + Defs: make(map[*ast.Ident]types.Object), + Uses: make(map[*ast.Ident]types.Object), + Implicits: make(map[ast.Node]types.Object), + Scopes: make(map[ast.Node]*types.Scope), + Selections: make(map[*ast.SelectorExpr]*types.Selection), + } + if err := types.NewChecker(tc, fset, pkg, info).Files(files); err != nil { + return nil, nil, err + } + + prog := ssa.NewProgram(fset, mode) + + // Create SSA packages for all imports. + // Order is not significant. + created := make(map[*types.Package]bool) + var createAll func(pkgs []*types.Package) + createAll = func(pkgs []*types.Package) { + for _, p := range pkgs { + if !created[p] { + created[p] = true + prog.CreatePackage(p, nil, nil, true) + createAll(p.Imports()) + } + } + } + createAll(pkg.Imports()) + + // Create and build the primary package. + ssapkg := prog.CreatePackage(pkg, files, info, false) + ssapkg.Build() + return ssapkg, info, nil +} diff --git a/vendor/honnef.co/go/tools/ssa/ssautil/switch.go b/vendor/honnef.co/go/tools/ssa/ssautil/switch.go new file mode 100644 index 0000000000..9c2f5d06ef --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/ssautil/switch.go @@ -0,0 +1,234 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssautil + +// This file implements discovery of switch and type-switch constructs +// from low-level control flow. +// +// Many techniques exist for compiling a high-level switch with +// constant cases to efficient machine code. The optimal choice will +// depend on the data type, the specific case values, the code in the +// body of each case, and the hardware. +// Some examples: +// - a lookup table (for a switch that maps constants to constants) +// - a computed goto +// - a binary tree +// - a perfect hash +// - a two-level switch (to partition constant strings by their first byte). + +import ( + "bytes" + "fmt" + "go/token" + "go/types" + + "honnef.co/go/tools/ssa" +) + +// A ConstCase represents a single constant comparison. +// It is part of a Switch. +type ConstCase struct { + Block *ssa.BasicBlock // block performing the comparison + Body *ssa.BasicBlock // body of the case + Value *ssa.Const // case comparand +} + +// A TypeCase represents a single type assertion. +// It is part of a Switch. +type TypeCase struct { + Block *ssa.BasicBlock // block performing the type assert + Body *ssa.BasicBlock // body of the case + Type types.Type // case type + Binding ssa.Value // value bound by this case +} + +// A Switch is a logical high-level control flow operation +// (a multiway branch) discovered by analysis of a CFG containing +// only if/else chains. It is not part of the ssa.Instruction set. +// +// One of ConstCases and TypeCases has length >= 2; +// the other is nil. +// +// In a value switch, the list of cases may contain duplicate constants. +// A type switch may contain duplicate types, or types assignable +// to an interface type also in the list. +// TODO(adonovan): eliminate such duplicates. +// +type Switch struct { + Start *ssa.BasicBlock // block containing start of if/else chain + X ssa.Value // the switch operand + ConstCases []ConstCase // ordered list of constant comparisons + TypeCases []TypeCase // ordered list of type assertions + Default *ssa.BasicBlock // successor if all comparisons fail +} + +func (sw *Switch) String() string { + // We represent each block by the String() of its + // first Instruction, e.g. "print(42:int)". + var buf bytes.Buffer + if sw.ConstCases != nil { + fmt.Fprintf(&buf, "switch %s {\n", sw.X.Name()) + for _, c := range sw.ConstCases { + fmt.Fprintf(&buf, "case %s: %s\n", c.Value, c.Body.Instrs[0]) + } + } else { + fmt.Fprintf(&buf, "switch %s.(type) {\n", sw.X.Name()) + for _, c := range sw.TypeCases { + fmt.Fprintf(&buf, "case %s %s: %s\n", + c.Binding.Name(), c.Type, c.Body.Instrs[0]) + } + } + if sw.Default != nil { + fmt.Fprintf(&buf, "default: %s\n", sw.Default.Instrs[0]) + } + fmt.Fprintf(&buf, "}") + return buf.String() +} + +// Switches examines the control-flow graph of fn and returns the +// set of inferred value and type switches. A value switch tests an +// ssa.Value for equality against two or more compile-time constant +// values. Switches involving link-time constants (addresses) are +// ignored. A type switch type-asserts an ssa.Value against two or +// more types. +// +// The switches are returned in dominance order. +// +// The resulting switches do not necessarily correspond to uses of the +// 'switch' keyword in the source: for example, a single source-level +// switch statement with non-constant cases may result in zero, one or +// many Switches, one per plural sequence of constant cases. +// Switches may even be inferred from if/else- or goto-based control flow. +// (In general, the control flow constructs of the source program +// cannot be faithfully reproduced from the SSA representation.) +// +func Switches(fn *ssa.Function) []Switch { + // Traverse the CFG in dominance order, so we don't + // enter an if/else-chain in the middle. + var switches []Switch + seen := make(map[*ssa.BasicBlock]bool) // TODO(adonovan): opt: use ssa.blockSet + for _, b := range fn.DomPreorder() { + if x, k := isComparisonBlock(b); x != nil { + // Block b starts a switch. + sw := Switch{Start: b, X: x} + valueSwitch(&sw, k, seen) + if len(sw.ConstCases) > 1 { + switches = append(switches, sw) + } + } + + if y, x, T := isTypeAssertBlock(b); y != nil { + // Block b starts a type switch. + sw := Switch{Start: b, X: x} + typeSwitch(&sw, y, T, seen) + if len(sw.TypeCases) > 1 { + switches = append(switches, sw) + } + } + } + return switches +} + +func valueSwitch(sw *Switch, k *ssa.Const, seen map[*ssa.BasicBlock]bool) { + b := sw.Start + x := sw.X + for x == sw.X { + if seen[b] { + break + } + seen[b] = true + + sw.ConstCases = append(sw.ConstCases, ConstCase{ + Block: b, + Body: b.Succs[0], + Value: k, + }) + b = b.Succs[1] + if len(b.Instrs) > 2 { + // Block b contains not just 'if x == k', + // so it may have side effects that + // make it unsafe to elide. + break + } + if len(b.Preds) != 1 { + // Block b has multiple predecessors, + // so it cannot be treated as a case. + break + } + x, k = isComparisonBlock(b) + } + sw.Default = b +} + +func typeSwitch(sw *Switch, y ssa.Value, T types.Type, seen map[*ssa.BasicBlock]bool) { + b := sw.Start + x := sw.X + for x == sw.X { + if seen[b] { + break + } + seen[b] = true + + sw.TypeCases = append(sw.TypeCases, TypeCase{ + Block: b, + Body: b.Succs[0], + Type: T, + Binding: y, + }) + b = b.Succs[1] + if len(b.Instrs) > 4 { + // Block b contains not just + // {TypeAssert; Extract #0; Extract #1; If} + // so it may have side effects that + // make it unsafe to elide. + break + } + if len(b.Preds) != 1 { + // Block b has multiple predecessors, + // so it cannot be treated as a case. + break + } + y, x, T = isTypeAssertBlock(b) + } + sw.Default = b +} + +// isComparisonBlock returns the operands (v, k) if a block ends with +// a comparison v==k, where k is a compile-time constant. +// +func isComparisonBlock(b *ssa.BasicBlock) (v ssa.Value, k *ssa.Const) { + if n := len(b.Instrs); n >= 2 { + if i, ok := b.Instrs[n-1].(*ssa.If); ok { + if binop, ok := i.Cond.(*ssa.BinOp); ok && binop.Block() == b && binop.Op == token.EQL { + if k, ok := binop.Y.(*ssa.Const); ok { + return binop.X, k + } + if k, ok := binop.X.(*ssa.Const); ok { + return binop.Y, k + } + } + } + } + return +} + +// isTypeAssertBlock returns the operands (y, x, T) if a block ends with +// a type assertion "if y, ok := x.(T); ok {". +// +func isTypeAssertBlock(b *ssa.BasicBlock) (y, x ssa.Value, T types.Type) { + if n := len(b.Instrs); n >= 4 { + if i, ok := b.Instrs[n-1].(*ssa.If); ok { + if ext1, ok := i.Cond.(*ssa.Extract); ok && ext1.Block() == b && ext1.Index == 1 { + if ta, ok := ext1.Tuple.(*ssa.TypeAssert); ok && ta.Block() == b { + // hack: relies upon instruction ordering. + if ext0, ok := b.Instrs[n-3].(*ssa.Extract); ok { + return ext0, ta.X, ta.AssertedType + } + } + } + } + } + return +} diff --git a/vendor/honnef.co/go/tools/ssa/ssautil/visit.go b/vendor/honnef.co/go/tools/ssa/ssautil/visit.go new file mode 100644 index 0000000000..5c14845f54 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/ssautil/visit.go @@ -0,0 +1,79 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssautil // import "honnef.co/go/tools/ssa/ssautil" + +import "honnef.co/go/tools/ssa" + +// This file defines utilities for visiting the SSA representation of +// a Program. +// +// TODO(adonovan): test coverage. + +// AllFunctions finds and returns the set of functions potentially +// needed by program prog, as determined by a simple linker-style +// reachability algorithm starting from the members and method-sets of +// each package. The result may include anonymous functions and +// synthetic wrappers. +// +// Precondition: all packages are built. +// +func AllFunctions(prog *ssa.Program) map[*ssa.Function]bool { + visit := visitor{ + prog: prog, + seen: make(map[*ssa.Function]bool), + } + visit.program() + return visit.seen +} + +type visitor struct { + prog *ssa.Program + seen map[*ssa.Function]bool +} + +func (visit *visitor) program() { + for _, pkg := range visit.prog.AllPackages() { + for _, mem := range pkg.Members { + if fn, ok := mem.(*ssa.Function); ok { + visit.function(fn) + } + } + } + for _, T := range visit.prog.RuntimeTypes() { + mset := visit.prog.MethodSets.MethodSet(T) + for i, n := 0, mset.Len(); i < n; i++ { + visit.function(visit.prog.MethodValue(mset.At(i))) + } + } +} + +func (visit *visitor) function(fn *ssa.Function) { + if !visit.seen[fn] { + visit.seen[fn] = true + var buf [10]*ssa.Value // avoid alloc in common case + for _, b := range fn.Blocks { + for _, instr := range b.Instrs { + for _, op := range instr.Operands(buf[:0]) { + if fn, ok := (*op).(*ssa.Function); ok { + visit.function(fn) + } + } + } + } + } +} + +// MainPackages returns the subset of the specified packages +// named "main" that define a main function. +// The result may include synthetic "testmain" packages. +func MainPackages(pkgs []*ssa.Package) []*ssa.Package { + var mains []*ssa.Package + for _, pkg := range pkgs { + if pkg.Pkg.Name() == "main" && pkg.Func("main") != nil { + mains = append(mains, pkg) + } + } + return mains +} diff --git a/vendor/honnef.co/go/tools/ssa/testmain.go b/vendor/honnef.co/go/tools/ssa/testmain.go new file mode 100644 index 0000000000..ea232ada95 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/testmain.go @@ -0,0 +1,267 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// CreateTestMainPackage synthesizes a main package that runs all the +// tests of the supplied packages. +// It is closely coupled to $GOROOT/src/cmd/go/test.go and $GOROOT/src/testing. +// +// TODO(adonovan): this file no longer needs to live in the ssa package. +// Move it to ssautil. + +import ( + "bytes" + "fmt" + "go/ast" + "go/parser" + "go/types" + "log" + "os" + "strings" + "text/template" +) + +// FindTests returns the Test, Benchmark, and Example functions +// (as defined by "go test") defined in the specified package, +// and its TestMain function, if any. +func FindTests(pkg *Package) (tests, benchmarks, examples []*Function, main *Function) { + prog := pkg.Prog + + // The first two of these may be nil: if the program doesn't import "testing", + // it can't contain any tests, but it may yet contain Examples. + var testSig *types.Signature // func(*testing.T) + var benchmarkSig *types.Signature // func(*testing.B) + var exampleSig = types.NewSignature(nil, nil, nil, false) // func() + + // Obtain the types from the parameters of testing.MainStart. + if testingPkg := prog.ImportedPackage("testing"); testingPkg != nil { + mainStart := testingPkg.Func("MainStart") + params := mainStart.Signature.Params() + testSig = funcField(params.At(1).Type()) + benchmarkSig = funcField(params.At(2).Type()) + + // Does the package define this function? + // func TestMain(*testing.M) + if f := pkg.Func("TestMain"); f != nil { + sig := f.Type().(*types.Signature) + starM := mainStart.Signature.Results().At(0).Type() // *testing.M + if sig.Results().Len() == 0 && + sig.Params().Len() == 1 && + types.Identical(sig.Params().At(0).Type(), starM) { + main = f + } + } + } + + // TODO(adonovan): use a stable order, e.g. lexical. + for _, mem := range pkg.Members { + if f, ok := mem.(*Function); ok && + ast.IsExported(f.Name()) && + strings.HasSuffix(prog.Fset.Position(f.Pos()).Filename, "_test.go") { + + switch { + case testSig != nil && isTestSig(f, "Test", testSig): + tests = append(tests, f) + case benchmarkSig != nil && isTestSig(f, "Benchmark", benchmarkSig): + benchmarks = append(benchmarks, f) + case isTestSig(f, "Example", exampleSig): + examples = append(examples, f) + default: + continue + } + } + } + return +} + +// Like isTest, but checks the signature too. +func isTestSig(f *Function, prefix string, sig *types.Signature) bool { + return isTest(f.Name(), prefix) && types.Identical(f.Signature, sig) +} + +// Given the type of one of the three slice parameters of testing.Main, +// returns the function type. +func funcField(slice types.Type) *types.Signature { + return slice.(*types.Slice).Elem().Underlying().(*types.Struct).Field(1).Type().(*types.Signature) +} + +// isTest tells whether name looks like a test (or benchmark, according to prefix). +// It is a Test (say) if there is a character after Test that is not a lower-case letter. +// We don't want TesticularCancer. +// Plundered from $GOROOT/src/cmd/go/test.go +func isTest(name, prefix string) bool { + if !strings.HasPrefix(name, prefix) { + return false + } + if len(name) == len(prefix) { // "Test" is ok + return true + } + return ast.IsExported(name[len(prefix):]) +} + +// CreateTestMainPackage creates and returns a synthetic "testmain" +// package for the specified package if it defines tests, benchmarks or +// executable examples, or nil otherwise. The new package is named +// "main" and provides a function named "main" that runs the tests, +// similar to the one that would be created by the 'go test' tool. +// +// Subsequent calls to prog.AllPackages include the new package. +// The package pkg must belong to the program prog. +func (prog *Program) CreateTestMainPackage(pkg *Package) *Package { + if pkg.Prog != prog { + log.Fatal("Package does not belong to Program") + } + + // Template data + var data struct { + Pkg *Package + Tests, Benchmarks, Examples []*Function + Main *Function + Go18 bool + } + data.Pkg = pkg + + // Enumerate tests. + data.Tests, data.Benchmarks, data.Examples, data.Main = FindTests(pkg) + if data.Main == nil && + data.Tests == nil && data.Benchmarks == nil && data.Examples == nil { + return nil + } + + // Synthesize source for testmain package. + path := pkg.Pkg.Path() + "$testmain" + tmpl := testmainTmpl + if testingPkg := prog.ImportedPackage("testing"); testingPkg != nil { + // In Go 1.8, testing.MainStart's first argument is an interface, not a func. + data.Go18 = types.IsInterface(testingPkg.Func("MainStart").Signature.Params().At(0).Type()) + } else { + // The program does not import "testing", but FindTests + // returned non-nil, which must mean there were Examples + // but no Test, Benchmark, or TestMain functions. + + // We'll simply call them from testmain.main; this will + // ensure they don't panic, but will not check any + // "Output:" comments. + // (We should not execute an Example that has no + // "Output:" comment, but it's impossible to tell here.) + tmpl = examplesOnlyTmpl + } + var buf bytes.Buffer + if err := tmpl.Execute(&buf, data); err != nil { + log.Fatalf("internal error expanding template for %s: %v", path, err) + } + if false { // debugging + fmt.Fprintln(os.Stderr, buf.String()) + } + + // Parse and type-check the testmain package. + f, err := parser.ParseFile(prog.Fset, path+".go", &buf, parser.Mode(0)) + if err != nil { + log.Fatalf("internal error parsing %s: %v", path, err) + } + conf := types.Config{ + DisableUnusedImportCheck: true, + Importer: importer{pkg}, + } + files := []*ast.File{f} + info := &types.Info{ + Types: make(map[ast.Expr]types.TypeAndValue), + Defs: make(map[*ast.Ident]types.Object), + Uses: make(map[*ast.Ident]types.Object), + Implicits: make(map[ast.Node]types.Object), + Scopes: make(map[ast.Node]*types.Scope), + Selections: make(map[*ast.SelectorExpr]*types.Selection), + } + testmainPkg, err := conf.Check(path, prog.Fset, files, info) + if err != nil { + log.Fatalf("internal error type-checking %s: %v", path, err) + } + + // Create and build SSA code. + testmain := prog.CreatePackage(testmainPkg, files, info, false) + testmain.SetDebugMode(false) + testmain.Build() + testmain.Func("main").Synthetic = "test main function" + testmain.Func("init").Synthetic = "package initializer" + return testmain +} + +// An implementation of types.Importer for an already loaded SSA program. +type importer struct { + pkg *Package // package under test; may be non-importable +} + +func (imp importer) Import(path string) (*types.Package, error) { + if p := imp.pkg.Prog.ImportedPackage(path); p != nil { + return p.Pkg, nil + } + if path == imp.pkg.Pkg.Path() { + return imp.pkg.Pkg, nil + } + return nil, fmt.Errorf("not found") // can't happen +} + +var testmainTmpl = template.Must(template.New("testmain").Parse(` +package main + +import "io" +import "os" +import "testing" +import p {{printf "%q" .Pkg.Pkg.Path}} + +{{if .Go18}} +type deps struct{} + +func (deps) ImportPath() string { return "" } +func (deps) MatchString(pat, str string) (bool, error) { return true, nil } +func (deps) StartCPUProfile(io.Writer) error { return nil } +func (deps) StartTestLog(io.Writer) {} +func (deps) StopCPUProfile() {} +func (deps) StopTestLog() error { return nil } +func (deps) WriteHeapProfile(io.Writer) error { return nil } +func (deps) WriteProfileTo(string, io.Writer, int) error { return nil } + +var match deps +{{else}} +func match(_, _ string) (bool, error) { return true, nil } +{{end}} + +func main() { + tests := []testing.InternalTest{ +{{range .Tests}} + { {{printf "%q" .Name}}, p.{{.Name}} }, +{{end}} + } + benchmarks := []testing.InternalBenchmark{ +{{range .Benchmarks}} + { {{printf "%q" .Name}}, p.{{.Name}} }, +{{end}} + } + examples := []testing.InternalExample{ +{{range .Examples}} + {Name: {{printf "%q" .Name}}, F: p.{{.Name}}}, +{{end}} + } + m := testing.MainStart(match, tests, benchmarks, examples) +{{with .Main}} + p.{{.Name}}(m) +{{else}} + os.Exit(m.Run()) +{{end}} +} + +`)) + +var examplesOnlyTmpl = template.Must(template.New("examples").Parse(` +package main + +import p {{printf "%q" .Pkg.Pkg.Path}} + +func main() { +{{range .Examples}} + p.{{.Name}}() +{{end}} +} +`)) diff --git a/vendor/honnef.co/go/tools/ssa/util.go b/vendor/honnef.co/go/tools/ssa/util.go new file mode 100644 index 0000000000..ddb1184609 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/util.go @@ -0,0 +1,119 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file defines a number of miscellaneous utility functions. + +import ( + "fmt" + "go/ast" + "go/token" + "go/types" + "io" + "os" + + "golang.org/x/tools/go/ast/astutil" +) + +//// AST utilities + +func unparen(e ast.Expr) ast.Expr { return astutil.Unparen(e) } + +// isBlankIdent returns true iff e is an Ident with name "_". +// They have no associated types.Object, and thus no type. +// +func isBlankIdent(e ast.Expr) bool { + id, ok := e.(*ast.Ident) + return ok && id.Name == "_" +} + +//// Type utilities. Some of these belong in go/types. + +// isPointer returns true for types whose underlying type is a pointer. +func isPointer(typ types.Type) bool { + _, ok := typ.Underlying().(*types.Pointer) + return ok +} + +func isInterface(T types.Type) bool { return types.IsInterface(T) } + +// deref returns a pointer's element type; otherwise it returns typ. +func deref(typ types.Type) types.Type { + if p, ok := typ.Underlying().(*types.Pointer); ok { + return p.Elem() + } + return typ +} + +// recvType returns the receiver type of method obj. +func recvType(obj *types.Func) types.Type { + return obj.Type().(*types.Signature).Recv().Type() +} + +// DefaultType returns the default "typed" type for an "untyped" type; +// it returns the incoming type for all other types. The default type +// for untyped nil is untyped nil. +// +// Exported to ssa/interp. +// +// TODO(adonovan): use go/types.DefaultType after 1.8. +// +func DefaultType(typ types.Type) types.Type { + if t, ok := typ.(*types.Basic); ok { + k := t.Kind() + switch k { + case types.UntypedBool: + k = types.Bool + case types.UntypedInt: + k = types.Int + case types.UntypedRune: + k = types.Rune + case types.UntypedFloat: + k = types.Float64 + case types.UntypedComplex: + k = types.Complex128 + case types.UntypedString: + k = types.String + } + typ = types.Typ[k] + } + return typ +} + +// logStack prints the formatted "start" message to stderr and +// returns a closure that prints the corresponding "end" message. +// Call using 'defer logStack(...)()' to show builder stack on panic. +// Don't forget trailing parens! +// +func logStack(format string, args ...interface{}) func() { + msg := fmt.Sprintf(format, args...) + io.WriteString(os.Stderr, msg) + io.WriteString(os.Stderr, "\n") + return func() { + io.WriteString(os.Stderr, msg) + io.WriteString(os.Stderr, " end\n") + } +} + +// newVar creates a 'var' for use in a types.Tuple. +func newVar(name string, typ types.Type) *types.Var { + return types.NewParam(token.NoPos, nil, name, typ) +} + +// anonVar creates an anonymous 'var' for use in a types.Tuple. +func anonVar(typ types.Type) *types.Var { + return newVar("", typ) +} + +var lenResults = types.NewTuple(anonVar(tInt)) + +// makeLen returns the len builtin specialized to type func(T)int. +func makeLen(T types.Type) *Builtin { + lenParams := types.NewTuple(anonVar(T)) + return &Builtin{ + name: "len", + sig: types.NewSignature(nil, lenParams, lenResults, false), + } +} diff --git a/vendor/honnef.co/go/tools/ssa/wrappers.go b/vendor/honnef.co/go/tools/ssa/wrappers.go new file mode 100644 index 0000000000..701dd90d7d --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/wrappers.go @@ -0,0 +1,294 @@ +// Copyright 2013 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package ssa + +// This file defines synthesis of Functions that delegate to declared +// methods; they come in three kinds: +// +// (1) wrappers: methods that wrap declared methods, performing +// implicit pointer indirections and embedded field selections. +// +// (2) thunks: funcs that wrap declared methods. Like wrappers, +// thunks perform indirections and field selections. The thunk's +// first parameter is used as the receiver for the method call. +// +// (3) bounds: funcs that wrap declared methods. The bound's sole +// free variable, supplied by a closure, is used as the receiver +// for the method call. No indirections or field selections are +// performed since they can be done before the call. + +import ( + "fmt" + + "go/types" +) + +// -- wrappers ----------------------------------------------------------- + +// makeWrapper returns a synthetic method that delegates to the +// declared method denoted by meth.Obj(), first performing any +// necessary pointer indirections or field selections implied by meth. +// +// The resulting method's receiver type is meth.Recv(). +// +// This function is versatile but quite subtle! Consider the +// following axes of variation when making changes: +// - optional receiver indirection +// - optional implicit field selections +// - meth.Obj() may denote a concrete or an interface method +// - the result may be a thunk or a wrapper. +// +// EXCLUSIVE_LOCKS_REQUIRED(prog.methodsMu) +// +func makeWrapper(prog *Program, sel *types.Selection) *Function { + obj := sel.Obj().(*types.Func) // the declared function + sig := sel.Type().(*types.Signature) // type of this wrapper + + var recv *types.Var // wrapper's receiver or thunk's params[0] + name := obj.Name() + var description string + var start int // first regular param + if sel.Kind() == types.MethodExpr { + name += "$thunk" + description = "thunk" + recv = sig.Params().At(0) + start = 1 + } else { + description = "wrapper" + recv = sig.Recv() + } + + description = fmt.Sprintf("%s for %s", description, sel.Obj()) + if prog.mode&LogSource != 0 { + defer logStack("make %s to (%s)", description, recv.Type())() + } + fn := &Function{ + name: name, + method: sel, + object: obj, + Signature: sig, + Synthetic: description, + Prog: prog, + pos: obj.Pos(), + } + fn.startBody() + fn.addSpilledParam(recv) + createParams(fn, start) + + indices := sel.Index() + + var v Value = fn.Locals[0] // spilled receiver + if isPointer(sel.Recv()) { + v = emitLoad(fn, v) + + // For simple indirection wrappers, perform an informative nil-check: + // "value method (T).f called using nil *T pointer" + if len(indices) == 1 && !isPointer(recvType(obj)) { + var c Call + c.Call.Value = &Builtin{ + name: "ssa:wrapnilchk", + sig: types.NewSignature(nil, + types.NewTuple(anonVar(sel.Recv()), anonVar(tString), anonVar(tString)), + types.NewTuple(anonVar(sel.Recv())), false), + } + c.Call.Args = []Value{ + v, + stringConst(deref(sel.Recv()).String()), + stringConst(sel.Obj().Name()), + } + c.setType(v.Type()) + v = fn.emit(&c) + } + } + + // Invariant: v is a pointer, either + // value of *A receiver param, or + // address of A spilled receiver. + + // We use pointer arithmetic (FieldAddr possibly followed by + // Load) in preference to value extraction (Field possibly + // preceded by Load). + + v = emitImplicitSelections(fn, v, indices[:len(indices)-1]) + + // Invariant: v is a pointer, either + // value of implicit *C field, or + // address of implicit C field. + + var c Call + if r := recvType(obj); !isInterface(r) { // concrete method + if !isPointer(r) { + v = emitLoad(fn, v) + } + c.Call.Value = prog.declaredFunc(obj) + c.Call.Args = append(c.Call.Args, v) + } else { + c.Call.Method = obj + c.Call.Value = emitLoad(fn, v) + } + for _, arg := range fn.Params[1:] { + c.Call.Args = append(c.Call.Args, arg) + } + emitTailCall(fn, &c) + fn.finishBody() + return fn +} + +// createParams creates parameters for wrapper method fn based on its +// Signature.Params, which do not include the receiver. +// start is the index of the first regular parameter to use. +// +func createParams(fn *Function, start int) { + var last *Parameter + tparams := fn.Signature.Params() + for i, n := start, tparams.Len(); i < n; i++ { + last = fn.addParamObj(tparams.At(i)) + } + if fn.Signature.Variadic() { + last.typ = types.NewSlice(last.typ) + } +} + +// -- bounds ----------------------------------------------------------- + +// makeBound returns a bound method wrapper (or "bound"), a synthetic +// function that delegates to a concrete or interface method denoted +// by obj. The resulting function has no receiver, but has one free +// variable which will be used as the method's receiver in the +// tail-call. +// +// Use MakeClosure with such a wrapper to construct a bound method +// closure. e.g.: +// +// type T int or: type T interface { meth() } +// func (t T) meth() +// var t T +// f := t.meth +// f() // calls t.meth() +// +// f is a closure of a synthetic wrapper defined as if by: +// +// f := func() { return t.meth() } +// +// Unlike makeWrapper, makeBound need perform no indirection or field +// selections because that can be done before the closure is +// constructed. +// +// EXCLUSIVE_LOCKS_ACQUIRED(meth.Prog.methodsMu) +// +func makeBound(prog *Program, obj *types.Func) *Function { + prog.methodsMu.Lock() + defer prog.methodsMu.Unlock() + fn, ok := prog.bounds[obj] + if !ok { + description := fmt.Sprintf("bound method wrapper for %s", obj) + if prog.mode&LogSource != 0 { + defer logStack("%s", description)() + } + fn = &Function{ + name: obj.Name() + "$bound", + object: obj, + Signature: changeRecv(obj.Type().(*types.Signature), nil), // drop receiver + Synthetic: description, + Prog: prog, + pos: obj.Pos(), + } + + fv := &FreeVar{name: "recv", typ: recvType(obj), parent: fn} + fn.FreeVars = []*FreeVar{fv} + fn.startBody() + createParams(fn, 0) + var c Call + + if !isInterface(recvType(obj)) { // concrete + c.Call.Value = prog.declaredFunc(obj) + c.Call.Args = []Value{fv} + } else { + c.Call.Value = fv + c.Call.Method = obj + } + for _, arg := range fn.Params { + c.Call.Args = append(c.Call.Args, arg) + } + emitTailCall(fn, &c) + fn.finishBody() + + prog.bounds[obj] = fn + } + return fn +} + +// -- thunks ----------------------------------------------------------- + +// makeThunk returns a thunk, a synthetic function that delegates to a +// concrete or interface method denoted by sel.Obj(). The resulting +// function has no receiver, but has an additional (first) regular +// parameter. +// +// Precondition: sel.Kind() == types.MethodExpr. +// +// type T int or: type T interface { meth() } +// func (t T) meth() +// f := T.meth +// var t T +// f(t) // calls t.meth() +// +// f is a synthetic wrapper defined as if by: +// +// f := func(t T) { return t.meth() } +// +// TODO(adonovan): opt: currently the stub is created even when used +// directly in a function call: C.f(i, 0). This is less efficient +// than inlining the stub. +// +// EXCLUSIVE_LOCKS_ACQUIRED(meth.Prog.methodsMu) +// +func makeThunk(prog *Program, sel *types.Selection) *Function { + if sel.Kind() != types.MethodExpr { + panic(sel) + } + + key := selectionKey{ + kind: sel.Kind(), + recv: sel.Recv(), + obj: sel.Obj(), + index: fmt.Sprint(sel.Index()), + indirect: sel.Indirect(), + } + + prog.methodsMu.Lock() + defer prog.methodsMu.Unlock() + + // Canonicalize key.recv to avoid constructing duplicate thunks. + canonRecv, ok := prog.canon.At(key.recv).(types.Type) + if !ok { + canonRecv = key.recv + prog.canon.Set(key.recv, canonRecv) + } + key.recv = canonRecv + + fn, ok := prog.thunks[key] + if !ok { + fn = makeWrapper(prog, sel) + if fn.Signature.Recv() != nil { + panic(fn) // unexpected receiver + } + prog.thunks[key] = fn + } + return fn +} + +func changeRecv(s *types.Signature, recv *types.Var) *types.Signature { + return types.NewSignature(recv, s.Params(), s.Results(), s.Variadic()) +} + +// selectionKey is like types.Selection but a usable map key. +type selectionKey struct { + kind types.SelectionKind + recv types.Type // canonicalized via Program.canon + obj types.Object + index string + indirect bool +} diff --git a/vendor/honnef.co/go/tools/ssa/write.go b/vendor/honnef.co/go/tools/ssa/write.go new file mode 100644 index 0000000000..89761a18a5 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssa/write.go @@ -0,0 +1,5 @@ +package ssa + +func NewJump(parent *BasicBlock) *Jump { + return &Jump{anInstruction{parent}} +} diff --git a/vendor/honnef.co/go/tools/ssautil/ssautil.go b/vendor/honnef.co/go/tools/ssautil/ssautil.go new file mode 100644 index 0000000000..a18f849ec2 --- /dev/null +++ b/vendor/honnef.co/go/tools/ssautil/ssautil.go @@ -0,0 +1,41 @@ +package ssautil + +import ( + "honnef.co/go/tools/ssa" +) + +func Reachable(from, to *ssa.BasicBlock) bool { + if from == to { + return true + } + if from.Dominates(to) { + return true + } + + found := false + Walk(from, func(b *ssa.BasicBlock) bool { + if b == to { + found = true + return false + } + return true + }) + return found +} + +func Walk(b *ssa.BasicBlock, fn func(*ssa.BasicBlock) bool) { + seen := map[*ssa.BasicBlock]bool{} + wl := []*ssa.BasicBlock{b} + for len(wl) > 0 { + b := wl[len(wl)-1] + wl = wl[:len(wl)-1] + if seen[b] { + continue + } + seen[b] = true + if !fn(b) { + continue + } + wl = append(wl, b.Succs...) + } +} diff --git a/vendor/honnef.co/go/tools/staticcheck/CONTRIBUTING.md b/vendor/honnef.co/go/tools/staticcheck/CONTRIBUTING.md new file mode 100644 index 0000000000..b12c7afc74 --- /dev/null +++ b/vendor/honnef.co/go/tools/staticcheck/CONTRIBUTING.md @@ -0,0 +1,15 @@ +# Contributing to staticcheck + +## Before filing an issue: + +### Are you having trouble building staticcheck? + +Check you have the latest version of its dependencies. Run +``` +go get -u honnef.co/go/tools/staticcheck +``` +If you still have problems, consider searching for existing issues before filing a new issue. + +## Before sending a pull request: + +Have you understood the purpose of staticcheck? Make sure to carefully read `README`. diff --git a/vendor/honnef.co/go/tools/staticcheck/buildtag.go b/vendor/honnef.co/go/tools/staticcheck/buildtag.go new file mode 100644 index 0000000000..888d3e9dc0 --- /dev/null +++ b/vendor/honnef.co/go/tools/staticcheck/buildtag.go @@ -0,0 +1,21 @@ +package staticcheck + +import ( + "go/ast" + "strings" + + . "honnef.co/go/tools/lint/lintdsl" +) + +func buildTags(f *ast.File) [][]string { + var out [][]string + for _, line := range strings.Split(Preamble(f), "\n") { + if !strings.HasPrefix(line, "+build ") { + continue + } + line = strings.TrimSpace(strings.TrimPrefix(line, "+build ")) + fields := strings.Fields(line) + out = append(out, fields) + } + return out +} diff --git a/vendor/honnef.co/go/tools/staticcheck/lint.go b/vendor/honnef.co/go/tools/staticcheck/lint.go new file mode 100644 index 0000000000..3a890b7bbd --- /dev/null +++ b/vendor/honnef.co/go/tools/staticcheck/lint.go @@ -0,0 +1,2817 @@ +// Package staticcheck contains a linter for Go source code. +package staticcheck // import "honnef.co/go/tools/staticcheck" + +import ( + "fmt" + "go/ast" + "go/constant" + "go/token" + "go/types" + htmltemplate "html/template" + "net/http" + "regexp" + "regexp/syntax" + "sort" + "strconv" + "strings" + "sync" + texttemplate "text/template" + + . "honnef.co/go/tools/arg" + "honnef.co/go/tools/deprecated" + "honnef.co/go/tools/functions" + "honnef.co/go/tools/internal/sharedcheck" + "honnef.co/go/tools/lint" + . "honnef.co/go/tools/lint/lintdsl" + "honnef.co/go/tools/ssa" + "honnef.co/go/tools/ssautil" + "honnef.co/go/tools/staticcheck/vrp" + + "golang.org/x/tools/go/ast/astutil" + "golang.org/x/tools/go/packages" +) + +func validRegexp(call *Call) { + arg := call.Args[0] + err := ValidateRegexp(arg.Value) + if err != nil { + arg.Invalid(err.Error()) + } +} + +type runeSlice []rune + +func (rs runeSlice) Len() int { return len(rs) } +func (rs runeSlice) Less(i int, j int) bool { return rs[i] < rs[j] } +func (rs runeSlice) Swap(i int, j int) { rs[i], rs[j] = rs[j], rs[i] } + +func utf8Cutset(call *Call) { + arg := call.Args[1] + if InvalidUTF8(arg.Value) { + arg.Invalid(MsgInvalidUTF8) + } +} + +func uniqueCutset(call *Call) { + arg := call.Args[1] + if !UniqueStringCutset(arg.Value) { + arg.Invalid(MsgNonUniqueCutset) + } +} + +func unmarshalPointer(name string, arg int) CallCheck { + return func(call *Call) { + if !Pointer(call.Args[arg].Value) { + call.Args[arg].Invalid(fmt.Sprintf("%s expects to unmarshal into a pointer, but the provided value is not a pointer", name)) + } + } +} + +func pointlessIntMath(call *Call) { + if ConvertedFromInt(call.Args[0].Value) { + call.Invalid(fmt.Sprintf("calling %s on a converted integer is pointless", CallName(call.Instr.Common()))) + } +} + +func checkValidHostPort(arg int) CallCheck { + return func(call *Call) { + if !ValidHostPort(call.Args[arg].Value) { + call.Args[arg].Invalid(MsgInvalidHostPort) + } + } +} + +var ( + checkRegexpRules = map[string]CallCheck{ + "regexp.MustCompile": validRegexp, + "regexp.Compile": validRegexp, + "regexp.Match": validRegexp, + "regexp.MatchReader": validRegexp, + "regexp.MatchString": validRegexp, + } + + checkTimeParseRules = map[string]CallCheck{ + "time.Parse": func(call *Call) { + arg := call.Args[Arg("time.Parse.layout")] + err := ValidateTimeLayout(arg.Value) + if err != nil { + arg.Invalid(err.Error()) + } + }, + } + + checkEncodingBinaryRules = map[string]CallCheck{ + "encoding/binary.Write": func(call *Call) { + arg := call.Args[Arg("encoding/binary.Write.data")] + if !CanBinaryMarshal(call.Job, arg.Value) { + arg.Invalid(fmt.Sprintf("value of type %s cannot be used with binary.Write", arg.Value.Value.Type())) + } + }, + } + + checkURLsRules = map[string]CallCheck{ + "net/url.Parse": func(call *Call) { + arg := call.Args[Arg("net/url.Parse.rawurl")] + err := ValidateURL(arg.Value) + if err != nil { + arg.Invalid(err.Error()) + } + }, + } + + checkSyncPoolValueRules = map[string]CallCheck{ + "(*sync.Pool).Put": func(call *Call) { + arg := call.Args[Arg("(*sync.Pool).Put.x")] + typ := arg.Value.Value.Type() + if !IsPointerLike(typ) { + arg.Invalid("argument should be pointer-like to avoid allocations") + } + }, + } + + checkRegexpFindAllRules = map[string]CallCheck{ + "(*regexp.Regexp).FindAll": RepeatZeroTimes("a FindAll method", 1), + "(*regexp.Regexp).FindAllIndex": RepeatZeroTimes("a FindAll method", 1), + "(*regexp.Regexp).FindAllString": RepeatZeroTimes("a FindAll method", 1), + "(*regexp.Regexp).FindAllStringIndex": RepeatZeroTimes("a FindAll method", 1), + "(*regexp.Regexp).FindAllStringSubmatch": RepeatZeroTimes("a FindAll method", 1), + "(*regexp.Regexp).FindAllStringSubmatchIndex": RepeatZeroTimes("a FindAll method", 1), + "(*regexp.Regexp).FindAllSubmatch": RepeatZeroTimes("a FindAll method", 1), + "(*regexp.Regexp).FindAllSubmatchIndex": RepeatZeroTimes("a FindAll method", 1), + } + + checkUTF8CutsetRules = map[string]CallCheck{ + "strings.IndexAny": utf8Cutset, + "strings.LastIndexAny": utf8Cutset, + "strings.ContainsAny": utf8Cutset, + "strings.Trim": utf8Cutset, + "strings.TrimLeft": utf8Cutset, + "strings.TrimRight": utf8Cutset, + } + + checkUniqueCutsetRules = map[string]CallCheck{ + "strings.Trim": uniqueCutset, + "strings.TrimLeft": uniqueCutset, + "strings.TrimRight": uniqueCutset, + } + + checkUnmarshalPointerRules = map[string]CallCheck{ + "encoding/xml.Unmarshal": unmarshalPointer("xml.Unmarshal", 1), + "(*encoding/xml.Decoder).Decode": unmarshalPointer("Decode", 0), + "(*encoding/xml.Decoder).DecodeElement": unmarshalPointer("DecodeElement", 0), + "encoding/json.Unmarshal": unmarshalPointer("json.Unmarshal", 1), + "(*encoding/json.Decoder).Decode": unmarshalPointer("Decode", 0), + } + + checkUnbufferedSignalChanRules = map[string]CallCheck{ + "os/signal.Notify": func(call *Call) { + arg := call.Args[Arg("os/signal.Notify.c")] + if UnbufferedChannel(arg.Value) { + arg.Invalid("the channel used with signal.Notify should be buffered") + } + }, + } + + checkMathIntRules = map[string]CallCheck{ + "math.Ceil": pointlessIntMath, + "math.Floor": pointlessIntMath, + "math.IsNaN": pointlessIntMath, + "math.Trunc": pointlessIntMath, + "math.IsInf": pointlessIntMath, + } + + checkStringsReplaceZeroRules = map[string]CallCheck{ + "strings.Replace": RepeatZeroTimes("strings.Replace", 3), + "bytes.Replace": RepeatZeroTimes("bytes.Replace", 3), + } + + checkListenAddressRules = map[string]CallCheck{ + "net/http.ListenAndServe": checkValidHostPort(0), + "net/http.ListenAndServeTLS": checkValidHostPort(0), + } + + checkBytesEqualIPRules = map[string]CallCheck{ + "bytes.Equal": func(call *Call) { + if ConvertedFrom(call.Args[Arg("bytes.Equal.a")].Value, "net.IP") && + ConvertedFrom(call.Args[Arg("bytes.Equal.b")].Value, "net.IP") { + call.Invalid("use net.IP.Equal to compare net.IPs, not bytes.Equal") + } + }, + } + + checkRegexpMatchLoopRules = map[string]CallCheck{ + "regexp.Match": loopedRegexp("regexp.Match"), + "regexp.MatchReader": loopedRegexp("regexp.MatchReader"), + "regexp.MatchString": loopedRegexp("regexp.MatchString"), + } +) + +type Checker struct { + CheckGenerated bool + funcDescs *functions.Descriptions + deprecatedObjs map[types.Object]string +} + +func NewChecker() *Checker { + return &Checker{} +} + +func (*Checker) Name() string { return "staticcheck" } +func (*Checker) Prefix() string { return "SA" } + +func (c *Checker) Checks() []lint.Check { + return []lint.Check{ + {ID: "SA1000", FilterGenerated: false, Fn: c.callChecker(checkRegexpRules)}, + {ID: "SA1001", FilterGenerated: false, Fn: c.CheckTemplate}, + {ID: "SA1002", FilterGenerated: false, Fn: c.callChecker(checkTimeParseRules)}, + {ID: "SA1003", FilterGenerated: false, Fn: c.callChecker(checkEncodingBinaryRules)}, + {ID: "SA1004", FilterGenerated: false, Fn: c.CheckTimeSleepConstant}, + {ID: "SA1005", FilterGenerated: false, Fn: c.CheckExec}, + {ID: "SA1006", FilterGenerated: false, Fn: c.CheckUnsafePrintf}, + {ID: "SA1007", FilterGenerated: false, Fn: c.callChecker(checkURLsRules)}, + {ID: "SA1008", FilterGenerated: false, Fn: c.CheckCanonicalHeaderKey}, + {ID: "SA1010", FilterGenerated: false, Fn: c.callChecker(checkRegexpFindAllRules)}, + {ID: "SA1011", FilterGenerated: false, Fn: c.callChecker(checkUTF8CutsetRules)}, + {ID: "SA1012", FilterGenerated: false, Fn: c.CheckNilContext}, + {ID: "SA1013", FilterGenerated: false, Fn: c.CheckSeeker}, + {ID: "SA1014", FilterGenerated: false, Fn: c.callChecker(checkUnmarshalPointerRules)}, + {ID: "SA1015", FilterGenerated: false, Fn: c.CheckLeakyTimeTick}, + {ID: "SA1016", FilterGenerated: false, Fn: c.CheckUntrappableSignal}, + {ID: "SA1017", FilterGenerated: false, Fn: c.callChecker(checkUnbufferedSignalChanRules)}, + {ID: "SA1018", FilterGenerated: false, Fn: c.callChecker(checkStringsReplaceZeroRules)}, + {ID: "SA1019", FilterGenerated: false, Fn: c.CheckDeprecated}, + {ID: "SA1020", FilterGenerated: false, Fn: c.callChecker(checkListenAddressRules)}, + {ID: "SA1021", FilterGenerated: false, Fn: c.callChecker(checkBytesEqualIPRules)}, + {ID: "SA1023", FilterGenerated: false, Fn: c.CheckWriterBufferModified}, + {ID: "SA1024", FilterGenerated: false, Fn: c.callChecker(checkUniqueCutsetRules)}, + {ID: "SA1025", FilterGenerated: false, Fn: c.CheckTimerResetReturnValue}, + + {ID: "SA2000", FilterGenerated: false, Fn: c.CheckWaitgroupAdd}, + {ID: "SA2001", FilterGenerated: false, Fn: c.CheckEmptyCriticalSection}, + {ID: "SA2002", FilterGenerated: false, Fn: c.CheckConcurrentTesting}, + {ID: "SA2003", FilterGenerated: false, Fn: c.CheckDeferLock}, + + {ID: "SA3000", FilterGenerated: false, Fn: c.CheckTestMainExit}, + {ID: "SA3001", FilterGenerated: false, Fn: c.CheckBenchmarkN}, + + {ID: "SA4000", FilterGenerated: false, Fn: c.CheckLhsRhsIdentical}, + {ID: "SA4001", FilterGenerated: false, Fn: c.CheckIneffectiveCopy}, + {ID: "SA4002", FilterGenerated: false, Fn: c.CheckDiffSizeComparison}, + {ID: "SA4003", FilterGenerated: false, Fn: c.CheckUnsignedComparison}, + {ID: "SA4004", FilterGenerated: false, Fn: c.CheckIneffectiveLoop}, + {ID: "SA4006", FilterGenerated: false, Fn: c.CheckUnreadVariableValues}, + {ID: "SA4008", FilterGenerated: false, Fn: c.CheckLoopCondition}, + {ID: "SA4009", FilterGenerated: false, Fn: c.CheckArgOverwritten}, + {ID: "SA4010", FilterGenerated: false, Fn: c.CheckIneffectiveAppend}, + {ID: "SA4011", FilterGenerated: false, Fn: c.CheckScopedBreak}, + {ID: "SA4012", FilterGenerated: false, Fn: c.CheckNaNComparison}, + {ID: "SA4013", FilterGenerated: false, Fn: c.CheckDoubleNegation}, + {ID: "SA4014", FilterGenerated: false, Fn: c.CheckRepeatedIfElse}, + {ID: "SA4015", FilterGenerated: false, Fn: c.callChecker(checkMathIntRules)}, + {ID: "SA4016", FilterGenerated: false, Fn: c.CheckSillyBitwiseOps}, + {ID: "SA4017", FilterGenerated: false, Fn: c.CheckPureFunctions}, + {ID: "SA4018", FilterGenerated: true, Fn: c.CheckSelfAssignment}, + {ID: "SA4019", FilterGenerated: true, Fn: c.CheckDuplicateBuildConstraints}, + + {ID: "SA5000", FilterGenerated: false, Fn: c.CheckNilMaps}, + {ID: "SA5001", FilterGenerated: false, Fn: c.CheckEarlyDefer}, + {ID: "SA5002", FilterGenerated: false, Fn: c.CheckInfiniteEmptyLoop}, + {ID: "SA5003", FilterGenerated: false, Fn: c.CheckDeferInInfiniteLoop}, + {ID: "SA5004", FilterGenerated: false, Fn: c.CheckLoopEmptyDefault}, + {ID: "SA5005", FilterGenerated: false, Fn: c.CheckCyclicFinalizer}, + {ID: "SA5007", FilterGenerated: false, Fn: c.CheckInfiniteRecursion}, + + {ID: "SA6000", FilterGenerated: false, Fn: c.callChecker(checkRegexpMatchLoopRules)}, + {ID: "SA6001", FilterGenerated: false, Fn: c.CheckMapBytesKey}, + {ID: "SA6002", FilterGenerated: false, Fn: c.callChecker(checkSyncPoolValueRules)}, + {ID: "SA6003", FilterGenerated: false, Fn: c.CheckRangeStringRunes}, + // {ID: "SA6004", FilterGenerated: false, Fn: c.CheckSillyRegexp}, + + {ID: "SA9001", FilterGenerated: false, Fn: c.CheckDubiousDeferInChannelRangeLoop}, + {ID: "SA9002", FilterGenerated: false, Fn: c.CheckNonOctalFileMode}, + {ID: "SA9003", FilterGenerated: false, Fn: c.CheckEmptyBranch}, + {ID: "SA9004", FilterGenerated: false, Fn: c.CheckMissingEnumTypesInDeclaration}, + } + + // "SA5006": c.CheckSliceOutOfBounds, + // "SA4007": c.CheckPredeterminedBooleanExprs, +} + +func (c *Checker) findDeprecated(prog *lint.Program) { + var docs []*ast.CommentGroup + var names []*ast.Ident + + doDocs := func(pkg *packages.Package, names []*ast.Ident, docs []*ast.CommentGroup) { + var alt string + for _, doc := range docs { + if doc == nil { + continue + } + parts := strings.Split(doc.Text(), "\n\n") + last := parts[len(parts)-1] + if !strings.HasPrefix(last, "Deprecated: ") { + continue + } + alt = last[len("Deprecated: "):] + alt = strings.Replace(alt, "\n", " ", -1) + break + } + if alt == "" { + return + } + + for _, name := range names { + obj := pkg.TypesInfo.ObjectOf(name) + c.deprecatedObjs[obj] = alt + } + } + + for _, pkg := range prog.AllPackages { + for _, f := range pkg.Syntax { + fn := func(node ast.Node) bool { + if node == nil { + return true + } + var ret bool + switch node := node.(type) { + case *ast.GenDecl: + switch node.Tok { + case token.TYPE, token.CONST, token.VAR: + docs = append(docs, node.Doc) + return true + default: + return false + } + case *ast.FuncDecl: + docs = append(docs, node.Doc) + names = []*ast.Ident{node.Name} + ret = false + case *ast.TypeSpec: + docs = append(docs, node.Doc) + names = []*ast.Ident{node.Name} + ret = true + case *ast.ValueSpec: + docs = append(docs, node.Doc) + names = node.Names + ret = false + case *ast.File: + return true + case *ast.StructType: + for _, field := range node.Fields.List { + doDocs(pkg, field.Names, []*ast.CommentGroup{field.Doc}) + } + return false + case *ast.InterfaceType: + for _, field := range node.Methods.List { + doDocs(pkg, field.Names, []*ast.CommentGroup{field.Doc}) + } + return false + default: + return false + } + if len(names) == 0 || len(docs) == 0 { + return ret + } + doDocs(pkg, names, docs) + + docs = docs[:0] + names = nil + return ret + } + ast.Inspect(f, fn) + } + } +} + +func (c *Checker) Init(prog *lint.Program) { + wg := &sync.WaitGroup{} + wg.Add(2) + go func() { + c.funcDescs = functions.NewDescriptions(prog.SSA) + for _, fn := range prog.AllFunctions { + if fn.Blocks != nil { + applyStdlibKnowledge(fn) + ssa.OptimizeBlocks(fn) + } + } + wg.Done() + }() + + go func() { + c.deprecatedObjs = map[types.Object]string{} + c.findDeprecated(prog) + wg.Done() + }() + + wg.Wait() +} + +func (c *Checker) isInLoop(b *ssa.BasicBlock) bool { + sets := c.funcDescs.Get(b.Parent()).Loops + for _, set := range sets { + if set[b] { + return true + } + } + return false +} + +func applyStdlibKnowledge(fn *ssa.Function) { + if len(fn.Blocks) == 0 { + return + } + + // comma-ok receiving from a time.Tick channel will never return + // ok == false, so any branching on the value of ok can be + // replaced with an unconditional jump. This will primarily match + // `for range time.Tick(x)` loops, but it can also match + // user-written code. + for _, block := range fn.Blocks { + if len(block.Instrs) < 3 { + continue + } + if len(block.Succs) != 2 { + continue + } + var instrs []*ssa.Instruction + for i, ins := range block.Instrs { + if _, ok := ins.(*ssa.DebugRef); ok { + continue + } + instrs = append(instrs, &block.Instrs[i]) + } + + for i, ins := range instrs { + unop, ok := (*ins).(*ssa.UnOp) + if !ok || unop.Op != token.ARROW { + continue + } + call, ok := unop.X.(*ssa.Call) + if !ok { + continue + } + if !IsCallTo(call.Common(), "time.Tick") { + continue + } + ex, ok := (*instrs[i+1]).(*ssa.Extract) + if !ok || ex.Tuple != unop || ex.Index != 1 { + continue + } + + ifstmt, ok := (*instrs[i+2]).(*ssa.If) + if !ok || ifstmt.Cond != ex { + continue + } + + *instrs[i+2] = ssa.NewJump(block) + succ := block.Succs[1] + block.Succs = block.Succs[0:1] + succ.RemovePred(block) + } + } +} + +func hasType(j *lint.Job, expr ast.Expr, name string) bool { + T := TypeOf(j, expr) + return IsType(T, name) +} + +func (c *Checker) CheckUntrappableSignal(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + if !IsCallToAnyAST(j, call, + "os/signal.Ignore", "os/signal.Notify", "os/signal.Reset") { + return true + } + for _, arg := range call.Args { + if conv, ok := arg.(*ast.CallExpr); ok && isName(j, conv.Fun, "os.Signal") { + arg = conv.Args[0] + } + + if isName(j, arg, "os.Kill") || isName(j, arg, "syscall.SIGKILL") { + j.Errorf(arg, "%s cannot be trapped (did you mean syscall.SIGTERM?)", Render(j, arg)) + } + if isName(j, arg, "syscall.SIGSTOP") { + j.Errorf(arg, "%s signal cannot be trapped", Render(j, arg)) + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckTemplate(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + var kind string + if IsCallToAST(j, call, "(*text/template.Template).Parse") { + kind = "text" + } else if IsCallToAST(j, call, "(*html/template.Template).Parse") { + kind = "html" + } else { + return true + } + sel := call.Fun.(*ast.SelectorExpr) + if !IsCallToAST(j, sel.X, "text/template.New") && + !IsCallToAST(j, sel.X, "html/template.New") { + // TODO(dh): this is a cheap workaround for templates with + // different delims. A better solution with less false + // negatives would use data flow analysis to see where the + // template comes from and where it has been + return true + } + s, ok := ExprToString(j, call.Args[Arg("(*text/template.Template).Parse.text")]) + if !ok { + return true + } + var err error + switch kind { + case "text": + _, err = texttemplate.New("").Parse(s) + case "html": + _, err = htmltemplate.New("").Parse(s) + } + if err != nil { + // TODO(dominikh): whitelist other parse errors, if any + if strings.Contains(err.Error(), "unexpected") { + j.Errorf(call.Args[Arg("(*text/template.Template).Parse.text")], "%s", err) + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckTimeSleepConstant(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + if !IsCallToAST(j, call, "time.Sleep") { + return true + } + lit, ok := call.Args[Arg("time.Sleep.d")].(*ast.BasicLit) + if !ok { + return true + } + n, err := strconv.Atoi(lit.Value) + if err != nil { + return true + } + if n == 0 || n > 120 { + // time.Sleep(0) is a seldom used pattern in concurrency + // tests. >120 might be intentional. 120 was chosen + // because the user could've meant 2 minutes. + return true + } + recommendation := "time.Sleep(time.Nanosecond)" + if n != 1 { + recommendation = fmt.Sprintf("time.Sleep(%d * time.Nanosecond)", n) + } + j.Errorf(call.Args[Arg("time.Sleep.d")], + "sleeping for %d nanoseconds is probably a bug. Be explicit if it isn't: %s", n, recommendation) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckWaitgroupAdd(j *lint.Job) { + fn := func(node ast.Node) bool { + g, ok := node.(*ast.GoStmt) + if !ok { + return true + } + fun, ok := g.Call.Fun.(*ast.FuncLit) + if !ok { + return true + } + if len(fun.Body.List) == 0 { + return true + } + stmt, ok := fun.Body.List[0].(*ast.ExprStmt) + if !ok { + return true + } + call, ok := stmt.X.(*ast.CallExpr) + if !ok { + return true + } + sel, ok := call.Fun.(*ast.SelectorExpr) + if !ok { + return true + } + fn, ok := ObjectOf(j, sel.Sel).(*types.Func) + if !ok { + return true + } + if fn.FullName() == "(*sync.WaitGroup).Add" { + j.Errorf(sel, "should call %s before starting the goroutine to avoid a race", + Render(j, stmt)) + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckInfiniteEmptyLoop(j *lint.Job) { + fn := func(node ast.Node) bool { + loop, ok := node.(*ast.ForStmt) + if !ok || len(loop.Body.List) != 0 || loop.Post != nil { + return true + } + + if loop.Init != nil { + // TODO(dh): this isn't strictly necessary, it just makes + // the check easier. + return true + } + // An empty loop is bad news in two cases: 1) The loop has no + // condition. In that case, it's just a loop that spins + // forever and as fast as it can, keeping a core busy. 2) The + // loop condition only consists of variable or field reads and + // operators on those. The only way those could change their + // value is with unsynchronised access, which constitutes a + // data race. + // + // If the condition contains any function calls, its behaviour + // is dynamic and the loop might terminate. Similarly for + // channel receives. + + if loop.Cond != nil && hasSideEffects(loop.Cond) { + return true + } + + j.Errorf(loop, "this loop will spin, using 100%% CPU") + if loop.Cond != nil { + j.Errorf(loop, "loop condition never changes or has a race condition") + } + + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckDeferInInfiniteLoop(j *lint.Job) { + fn := func(node ast.Node) bool { + mightExit := false + var defers []ast.Stmt + loop, ok := node.(*ast.ForStmt) + if !ok || loop.Cond != nil { + return true + } + fn2 := func(node ast.Node) bool { + switch stmt := node.(type) { + case *ast.ReturnStmt: + mightExit = true + case *ast.BranchStmt: + // TODO(dominikh): if this sees a break in a switch or + // select, it doesn't check if it breaks the loop or + // just the select/switch. This causes some false + // negatives. + if stmt.Tok == token.BREAK { + mightExit = true + } + case *ast.DeferStmt: + defers = append(defers, stmt) + case *ast.FuncLit: + // Don't look into function bodies + return false + } + return true + } + ast.Inspect(loop.Body, fn2) + if mightExit { + return true + } + for _, stmt := range defers { + j.Errorf(stmt, "defers in this infinite loop will never run") + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckDubiousDeferInChannelRangeLoop(j *lint.Job) { + fn := func(node ast.Node) bool { + loop, ok := node.(*ast.RangeStmt) + if !ok { + return true + } + typ := TypeOf(j, loop.X) + _, ok = typ.Underlying().(*types.Chan) + if !ok { + return true + } + fn2 := func(node ast.Node) bool { + switch stmt := node.(type) { + case *ast.DeferStmt: + j.Errorf(stmt, "defers in this range loop won't run unless the channel gets closed") + case *ast.FuncLit: + // Don't look into function bodies + return false + } + return true + } + ast.Inspect(loop.Body, fn2) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckTestMainExit(j *lint.Job) { + fn := func(node ast.Node) bool { + if !isTestMain(j, node) { + return true + } + + arg := ObjectOf(j, node.(*ast.FuncDecl).Type.Params.List[0].Names[0]) + callsRun := false + fn2 := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + sel, ok := call.Fun.(*ast.SelectorExpr) + if !ok { + return true + } + ident, ok := sel.X.(*ast.Ident) + if !ok { + return true + } + if arg != ObjectOf(j, ident) { + return true + } + if sel.Sel.Name == "Run" { + callsRun = true + return false + } + return true + } + ast.Inspect(node.(*ast.FuncDecl).Body, fn2) + + callsExit := false + fn3 := func(node ast.Node) bool { + if IsCallToAST(j, node, "os.Exit") { + callsExit = true + return false + } + return true + } + ast.Inspect(node.(*ast.FuncDecl).Body, fn3) + if !callsExit && callsRun { + j.Errorf(node, "TestMain should call os.Exit to set exit code") + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func isTestMain(j *lint.Job, node ast.Node) bool { + decl, ok := node.(*ast.FuncDecl) + if !ok { + return false + } + if decl.Name.Name != "TestMain" { + return false + } + if len(decl.Type.Params.List) != 1 { + return false + } + arg := decl.Type.Params.List[0] + if len(arg.Names) != 1 { + return false + } + return IsOfType(j, arg.Type, "*testing.M") +} + +func (c *Checker) CheckExec(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + if !IsCallToAST(j, call, "os/exec.Command") { + return true + } + val, ok := ExprToString(j, call.Args[Arg("os/exec.Command.name")]) + if !ok { + return true + } + if !strings.Contains(val, " ") || strings.Contains(val, `\`) || strings.Contains(val, "/") { + return true + } + j.Errorf(call.Args[Arg("os/exec.Command.name")], + "first argument to exec.Command looks like a shell command, but a program name or path are expected") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckLoopEmptyDefault(j *lint.Job) { + fn := func(node ast.Node) bool { + loop, ok := node.(*ast.ForStmt) + if !ok || len(loop.Body.List) != 1 || loop.Cond != nil || loop.Init != nil { + return true + } + sel, ok := loop.Body.List[0].(*ast.SelectStmt) + if !ok { + return true + } + for _, c := range sel.Body.List { + if comm, ok := c.(*ast.CommClause); ok && comm.Comm == nil && len(comm.Body) == 0 { + j.Errorf(comm, "should not have an empty default case in a for+select loop. The loop will spin.") + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckLhsRhsIdentical(j *lint.Job) { + fn := func(node ast.Node) bool { + op, ok := node.(*ast.BinaryExpr) + if !ok { + return true + } + switch op.Op { + case token.EQL, token.NEQ: + if basic, ok := TypeOf(j, op.X).(*types.Basic); ok { + if kind := basic.Kind(); kind == types.Float32 || kind == types.Float64 { + // f == f and f != f might be used to check for NaN + return true + } + } + case token.SUB, token.QUO, token.AND, token.REM, token.OR, token.XOR, token.AND_NOT, + token.LAND, token.LOR, token.LSS, token.GTR, token.LEQ, token.GEQ: + default: + // For some ops, such as + and *, it can make sense to + // have identical operands + return true + } + + if Render(j, op.X) != Render(j, op.Y) { + return true + } + j.Errorf(op, "identical expressions on the left and right side of the '%s' operator", op.Op) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckScopedBreak(j *lint.Job) { + fn := func(node ast.Node) bool { + var body *ast.BlockStmt + switch node := node.(type) { + case *ast.ForStmt: + body = node.Body + case *ast.RangeStmt: + body = node.Body + default: + return true + } + for _, stmt := range body.List { + var blocks [][]ast.Stmt + switch stmt := stmt.(type) { + case *ast.SwitchStmt: + for _, c := range stmt.Body.List { + blocks = append(blocks, c.(*ast.CaseClause).Body) + } + case *ast.SelectStmt: + for _, c := range stmt.Body.List { + blocks = append(blocks, c.(*ast.CommClause).Body) + } + default: + continue + } + + for _, body := range blocks { + if len(body) == 0 { + continue + } + lasts := []ast.Stmt{body[len(body)-1]} + // TODO(dh): unfold all levels of nested block + // statements, not just a single level if statement + if ifs, ok := lasts[0].(*ast.IfStmt); ok { + if len(ifs.Body.List) == 0 { + continue + } + lasts[0] = ifs.Body.List[len(ifs.Body.List)-1] + + if block, ok := ifs.Else.(*ast.BlockStmt); ok { + if len(block.List) != 0 { + lasts = append(lasts, block.List[len(block.List)-1]) + } + } + } + for _, last := range lasts { + branch, ok := last.(*ast.BranchStmt) + if !ok || branch.Tok != token.BREAK || branch.Label != nil { + continue + } + j.Errorf(branch, "ineffective break statement. Did you mean to break out of the outer loop?") + } + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckUnsafePrintf(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + if !IsCallToAnyAST(j, call, "fmt.Printf", "fmt.Sprintf", "log.Printf") { + return true + } + if len(call.Args) != 1 { + return true + } + switch call.Args[Arg("fmt.Printf.format")].(type) { + case *ast.CallExpr, *ast.Ident: + default: + return true + } + j.Errorf(call.Args[Arg("fmt.Printf.format")], + "printf-style function with dynamic first argument and no further arguments should use print-style function instead") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckEarlyDefer(j *lint.Job) { + fn := func(node ast.Node) bool { + block, ok := node.(*ast.BlockStmt) + if !ok { + return true + } + if len(block.List) < 2 { + return true + } + for i, stmt := range block.List { + if i == len(block.List)-1 { + break + } + assign, ok := stmt.(*ast.AssignStmt) + if !ok { + continue + } + if len(assign.Rhs) != 1 { + continue + } + if len(assign.Lhs) < 2 { + continue + } + if lhs, ok := assign.Lhs[len(assign.Lhs)-1].(*ast.Ident); ok && lhs.Name == "_" { + continue + } + call, ok := assign.Rhs[0].(*ast.CallExpr) + if !ok { + continue + } + sig, ok := TypeOf(j, call.Fun).(*types.Signature) + if !ok { + continue + } + if sig.Results().Len() < 2 { + continue + } + last := sig.Results().At(sig.Results().Len() - 1) + // FIXME(dh): check that it's error from universe, not + // another type of the same name + if last.Type().String() != "error" { + continue + } + lhs, ok := assign.Lhs[0].(*ast.Ident) + if !ok { + continue + } + def, ok := block.List[i+1].(*ast.DeferStmt) + if !ok { + continue + } + sel, ok := def.Call.Fun.(*ast.SelectorExpr) + if !ok { + continue + } + ident, ok := selectorX(sel).(*ast.Ident) + if !ok { + continue + } + if ident.Obj != lhs.Obj { + continue + } + if sel.Sel.Name != "Close" { + continue + } + j.Errorf(def, "should check returned error before deferring %s", Render(j, def.Call)) + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func selectorX(sel *ast.SelectorExpr) ast.Node { + switch x := sel.X.(type) { + case *ast.SelectorExpr: + return selectorX(x) + default: + return x + } +} + +func (c *Checker) CheckEmptyCriticalSection(j *lint.Job) { + // Initially it might seem like this check would be easier to + // implement in SSA. After all, we're only checking for two + // consecutive method calls. In reality, however, there may be any + // number of other instructions between the lock and unlock, while + // still constituting an empty critical section. For example, + // given `m.x().Lock(); m.x().Unlock()`, there will be a call to + // x(). In the AST-based approach, this has a tiny potential for a + // false positive (the second call to x might be doing work that + // is protected by the mutex). In an SSA-based approach, however, + // it would miss a lot of real bugs. + + mutexParams := func(s ast.Stmt) (x ast.Expr, funcName string, ok bool) { + expr, ok := s.(*ast.ExprStmt) + if !ok { + return nil, "", false + } + call, ok := expr.X.(*ast.CallExpr) + if !ok { + return nil, "", false + } + sel, ok := call.Fun.(*ast.SelectorExpr) + if !ok { + return nil, "", false + } + + fn, ok := ObjectOf(j, sel.Sel).(*types.Func) + if !ok { + return nil, "", false + } + sig := fn.Type().(*types.Signature) + if sig.Params().Len() != 0 || sig.Results().Len() != 0 { + return nil, "", false + } + + return sel.X, fn.Name(), true + } + + fn := func(node ast.Node) bool { + block, ok := node.(*ast.BlockStmt) + if !ok { + return true + } + if len(block.List) < 2 { + return true + } + for i := range block.List[:len(block.List)-1] { + sel1, method1, ok1 := mutexParams(block.List[i]) + sel2, method2, ok2 := mutexParams(block.List[i+1]) + + if !ok1 || !ok2 || Render(j, sel1) != Render(j, sel2) { + continue + } + if (method1 == "Lock" && method2 == "Unlock") || + (method1 == "RLock" && method2 == "RUnlock") { + j.Errorf(block.List[i+1], "empty critical section") + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +// cgo produces code like fn(&*_Cvar_kSomeCallbacks) which we don't +// want to flag. +var cgoIdent = regexp.MustCompile(`^_C(func|var)_.+$`) + +func (c *Checker) CheckIneffectiveCopy(j *lint.Job) { + fn := func(node ast.Node) bool { + if unary, ok := node.(*ast.UnaryExpr); ok { + if star, ok := unary.X.(*ast.StarExpr); ok && unary.Op == token.AND { + ident, ok := star.X.(*ast.Ident) + if !ok || !cgoIdent.MatchString(ident.Name) { + j.Errorf(unary, "&*x will be simplified to x. It will not copy x.") + } + } + } + + if star, ok := node.(*ast.StarExpr); ok { + if unary, ok := star.X.(*ast.UnaryExpr); ok && unary.Op == token.AND { + j.Errorf(star, "*&x will be simplified to x. It will not copy x.") + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckDiffSizeComparison(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + for _, b := range ssafn.Blocks { + for _, ins := range b.Instrs { + binop, ok := ins.(*ssa.BinOp) + if !ok { + continue + } + if binop.Op != token.EQL && binop.Op != token.NEQ { + continue + } + _, ok1 := binop.X.(*ssa.Slice) + _, ok2 := binop.Y.(*ssa.Slice) + if !ok1 && !ok2 { + continue + } + r := c.funcDescs.Get(ssafn).Ranges + r1, ok1 := r.Get(binop.X).(vrp.StringInterval) + r2, ok2 := r.Get(binop.Y).(vrp.StringInterval) + if !ok1 || !ok2 { + continue + } + if r1.Length.Intersection(r2.Length).Empty() { + j.Errorf(binop, "comparing strings of different sizes for equality will always return false") + } + } + } + } +} + +func (c *Checker) CheckCanonicalHeaderKey(j *lint.Job) { + fn := func(node ast.Node) bool { + assign, ok := node.(*ast.AssignStmt) + if ok { + // TODO(dh): This risks missing some Header reads, for + // example in `h1["foo"] = h2["foo"]` – these edge + // cases are probably rare enough to ignore for now. + for _, expr := range assign.Lhs { + op, ok := expr.(*ast.IndexExpr) + if !ok { + continue + } + if hasType(j, op.X, "net/http.Header") { + return false + } + } + return true + } + op, ok := node.(*ast.IndexExpr) + if !ok { + return true + } + if !hasType(j, op.X, "net/http.Header") { + return true + } + s, ok := ExprToString(j, op.Index) + if !ok { + return true + } + if s == http.CanonicalHeaderKey(s) { + return true + } + j.Errorf(op, "keys in http.Header are canonicalized, %q is not canonical; fix the constant or use http.CanonicalHeaderKey", s) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckBenchmarkN(j *lint.Job) { + fn := func(node ast.Node) bool { + assign, ok := node.(*ast.AssignStmt) + if !ok { + return true + } + if len(assign.Lhs) != 1 || len(assign.Rhs) != 1 { + return true + } + sel, ok := assign.Lhs[0].(*ast.SelectorExpr) + if !ok { + return true + } + if sel.Sel.Name != "N" { + return true + } + if !hasType(j, sel.X, "*testing.B") { + return true + } + j.Errorf(assign, "should not assign to %s", Render(j, sel)) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckUnreadVariableValues(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + if IsExample(ssafn) { + continue + } + node := ssafn.Syntax() + if node == nil { + continue + } + + ast.Inspect(node, func(node ast.Node) bool { + assign, ok := node.(*ast.AssignStmt) + if !ok { + return true + } + if len(assign.Lhs) > 1 && len(assign.Rhs) == 1 { + // Either a function call with multiple return values, + // or a comma-ok assignment + + val, _ := ssafn.ValueForExpr(assign.Rhs[0]) + if val == nil { + return true + } + refs := val.Referrers() + if refs == nil { + return true + } + for _, ref := range *refs { + ex, ok := ref.(*ssa.Extract) + if !ok { + continue + } + exrefs := ex.Referrers() + if exrefs == nil { + continue + } + if len(FilterDebug(*exrefs)) == 0 { + lhs := assign.Lhs[ex.Index] + if ident, ok := lhs.(*ast.Ident); !ok || ok && ident.Name == "_" { + continue + } + j.Errorf(lhs, "this value of %s is never used", lhs) + } + } + return true + } + for i, lhs := range assign.Lhs { + rhs := assign.Rhs[i] + if ident, ok := lhs.(*ast.Ident); !ok || ok && ident.Name == "_" { + continue + } + val, _ := ssafn.ValueForExpr(rhs) + if val == nil { + continue + } + + refs := val.Referrers() + if refs == nil { + // TODO investigate why refs can be nil + return true + } + if len(FilterDebug(*refs)) == 0 { + j.Errorf(lhs, "this value of %s is never used", lhs) + } + } + return true + }) + } +} + +func (c *Checker) CheckPredeterminedBooleanExprs(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + for _, block := range ssafn.Blocks { + for _, ins := range block.Instrs { + ssabinop, ok := ins.(*ssa.BinOp) + if !ok { + continue + } + switch ssabinop.Op { + case token.GTR, token.LSS, token.EQL, token.NEQ, token.LEQ, token.GEQ: + default: + continue + } + + xs, ok1 := consts(ssabinop.X, nil, nil) + ys, ok2 := consts(ssabinop.Y, nil, nil) + if !ok1 || !ok2 || len(xs) == 0 || len(ys) == 0 { + continue + } + + trues := 0 + for _, x := range xs { + for _, y := range ys { + if x.Value == nil { + if y.Value == nil { + trues++ + } + continue + } + if constant.Compare(x.Value, ssabinop.Op, y.Value) { + trues++ + } + } + } + b := trues != 0 + if trues == 0 || trues == len(xs)*len(ys) { + j.Errorf(ssabinop, "binary expression is always %t for all possible values (%s %s %s)", + b, xs, ssabinop.Op, ys) + } + } + } + } +} + +func (c *Checker) CheckNilMaps(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + for _, block := range ssafn.Blocks { + for _, ins := range block.Instrs { + mu, ok := ins.(*ssa.MapUpdate) + if !ok { + continue + } + c, ok := mu.Map.(*ssa.Const) + if !ok { + continue + } + if c.Value != nil { + continue + } + j.Errorf(mu, "assignment to nil map") + } + } + } +} + +func (c *Checker) CheckUnsignedComparison(j *lint.Job) { + fn := func(node ast.Node) bool { + expr, ok := node.(*ast.BinaryExpr) + if !ok { + return true + } + tx := TypeOf(j, expr.X) + basic, ok := tx.Underlying().(*types.Basic) + if !ok { + return true + } + if (basic.Info() & types.IsUnsigned) == 0 { + return true + } + lit, ok := expr.Y.(*ast.BasicLit) + if !ok || lit.Value != "0" { + return true + } + switch expr.Op { + case token.GEQ: + j.Errorf(expr, "unsigned values are always >= 0") + case token.LSS: + j.Errorf(expr, "unsigned values are never < 0") + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func consts(val ssa.Value, out []*ssa.Const, visitedPhis map[string]bool) ([]*ssa.Const, bool) { + if visitedPhis == nil { + visitedPhis = map[string]bool{} + } + var ok bool + switch val := val.(type) { + case *ssa.Phi: + if visitedPhis[val.Name()] { + break + } + visitedPhis[val.Name()] = true + vals := val.Operands(nil) + for _, phival := range vals { + out, ok = consts(*phival, out, visitedPhis) + if !ok { + return nil, false + } + } + case *ssa.Const: + out = append(out, val) + case *ssa.Convert: + out, ok = consts(val.X, out, visitedPhis) + if !ok { + return nil, false + } + default: + return nil, false + } + if len(out) < 2 { + return out, true + } + uniq := []*ssa.Const{out[0]} + for _, val := range out[1:] { + if val.Value == uniq[len(uniq)-1].Value { + continue + } + uniq = append(uniq, val) + } + return uniq, true +} + +func (c *Checker) CheckLoopCondition(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + fn := func(node ast.Node) bool { + loop, ok := node.(*ast.ForStmt) + if !ok { + return true + } + if loop.Init == nil || loop.Cond == nil || loop.Post == nil { + return true + } + init, ok := loop.Init.(*ast.AssignStmt) + if !ok || len(init.Lhs) != 1 || len(init.Rhs) != 1 { + return true + } + cond, ok := loop.Cond.(*ast.BinaryExpr) + if !ok { + return true + } + x, ok := cond.X.(*ast.Ident) + if !ok { + return true + } + lhs, ok := init.Lhs[0].(*ast.Ident) + if !ok { + return true + } + if x.Obj != lhs.Obj { + return true + } + if _, ok := loop.Post.(*ast.IncDecStmt); !ok { + return true + } + + v, isAddr := ssafn.ValueForExpr(cond.X) + if v == nil || isAddr { + return true + } + switch v := v.(type) { + case *ssa.Phi: + ops := v.Operands(nil) + if len(ops) != 2 { + return true + } + _, ok := (*ops[0]).(*ssa.Const) + if !ok { + return true + } + sigma, ok := (*ops[1]).(*ssa.Sigma) + if !ok { + return true + } + if sigma.X != v { + return true + } + case *ssa.UnOp: + return true + } + j.Errorf(cond, "variable in loop condition never changes") + + return true + } + Inspect(ssafn.Syntax(), fn) + } +} + +func (c *Checker) CheckArgOverwritten(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + fn := func(node ast.Node) bool { + var typ *ast.FuncType + var body *ast.BlockStmt + switch fn := node.(type) { + case *ast.FuncDecl: + typ = fn.Type + body = fn.Body + case *ast.FuncLit: + typ = fn.Type + body = fn.Body + } + if body == nil { + return true + } + if len(typ.Params.List) == 0 { + return true + } + for _, field := range typ.Params.List { + for _, arg := range field.Names { + obj := ObjectOf(j, arg) + var ssaobj *ssa.Parameter + for _, param := range ssafn.Params { + if param.Object() == obj { + ssaobj = param + break + } + } + if ssaobj == nil { + continue + } + refs := ssaobj.Referrers() + if refs == nil { + continue + } + if len(FilterDebug(*refs)) != 0 { + continue + } + + assigned := false + ast.Inspect(body, func(node ast.Node) bool { + assign, ok := node.(*ast.AssignStmt) + if !ok { + return true + } + for _, lhs := range assign.Lhs { + ident, ok := lhs.(*ast.Ident) + if !ok { + continue + } + if ObjectOf(j, ident) == obj { + assigned = true + return false + } + } + return true + }) + if assigned { + j.Errorf(arg, "argument %s is overwritten before first use", arg) + } + } + } + return true + } + Inspect(ssafn.Syntax(), fn) + } +} + +func (c *Checker) CheckIneffectiveLoop(j *lint.Job) { + // This check detects some, but not all unconditional loop exits. + // We give up in the following cases: + // + // - a goto anywhere in the loop. The goto might skip over our + // return, and we don't check that it doesn't. + // + // - any nested, unlabelled continue, even if it is in another + // loop or closure. + fn := func(node ast.Node) bool { + var body *ast.BlockStmt + switch fn := node.(type) { + case *ast.FuncDecl: + body = fn.Body + case *ast.FuncLit: + body = fn.Body + default: + return true + } + if body == nil { + return true + } + labels := map[*ast.Object]ast.Stmt{} + ast.Inspect(body, func(node ast.Node) bool { + label, ok := node.(*ast.LabeledStmt) + if !ok { + return true + } + labels[label.Label.Obj] = label.Stmt + return true + }) + + ast.Inspect(body, func(node ast.Node) bool { + var loop ast.Node + var body *ast.BlockStmt + switch node := node.(type) { + case *ast.ForStmt: + body = node.Body + loop = node + case *ast.RangeStmt: + typ := TypeOf(j, node.X) + if _, ok := typ.Underlying().(*types.Map); ok { + // looping once over a map is a valid pattern for + // getting an arbitrary element. + return true + } + body = node.Body + loop = node + default: + return true + } + if len(body.List) < 2 { + // avoid flagging the somewhat common pattern of using + // a range loop to get the first element in a slice, + // or the first rune in a string. + return true + } + var unconditionalExit ast.Node + hasBranching := false + for _, stmt := range body.List { + switch stmt := stmt.(type) { + case *ast.BranchStmt: + switch stmt.Tok { + case token.BREAK: + if stmt.Label == nil || labels[stmt.Label.Obj] == loop { + unconditionalExit = stmt + } + case token.CONTINUE: + if stmt.Label == nil || labels[stmt.Label.Obj] == loop { + unconditionalExit = nil + return false + } + } + case *ast.ReturnStmt: + unconditionalExit = stmt + case *ast.IfStmt, *ast.ForStmt, *ast.RangeStmt, *ast.SwitchStmt, *ast.SelectStmt: + hasBranching = true + } + } + if unconditionalExit == nil || !hasBranching { + return false + } + ast.Inspect(body, func(node ast.Node) bool { + if branch, ok := node.(*ast.BranchStmt); ok { + + switch branch.Tok { + case token.GOTO: + unconditionalExit = nil + return false + case token.CONTINUE: + if branch.Label != nil && labels[branch.Label.Obj] != loop { + return true + } + unconditionalExit = nil + return false + } + } + return true + }) + if unconditionalExit != nil { + j.Errorf(unconditionalExit, "the surrounding loop is unconditionally terminated") + } + return true + }) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckNilContext(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + if len(call.Args) == 0 { + return true + } + if typ, ok := TypeOf(j, call.Args[0]).(*types.Basic); !ok || typ.Kind() != types.UntypedNil { + return true + } + sig, ok := TypeOf(j, call.Fun).(*types.Signature) + if !ok { + return true + } + if sig.Params().Len() == 0 { + return true + } + if !IsType(sig.Params().At(0).Type(), "context.Context") { + return true + } + j.Errorf(call.Args[0], + "do not pass a nil Context, even if a function permits it; pass context.TODO if you are unsure about which Context to use") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckSeeker(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + sel, ok := call.Fun.(*ast.SelectorExpr) + if !ok { + return true + } + if sel.Sel.Name != "Seek" { + return true + } + if len(call.Args) != 2 { + return true + } + arg0, ok := call.Args[Arg("(io.Seeker).Seek.offset")].(*ast.SelectorExpr) + if !ok { + return true + } + switch arg0.Sel.Name { + case "SeekStart", "SeekCurrent", "SeekEnd": + default: + return true + } + pkg, ok := arg0.X.(*ast.Ident) + if !ok { + return true + } + if pkg.Name != "io" { + return true + } + j.Errorf(call, "the first argument of io.Seeker is the offset, but an io.Seek* constant is being used instead") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckIneffectiveAppend(j *lint.Job) { + isAppend := func(ins ssa.Value) bool { + call, ok := ins.(*ssa.Call) + if !ok { + return false + } + if call.Call.IsInvoke() { + return false + } + if builtin, ok := call.Call.Value.(*ssa.Builtin); !ok || builtin.Name() != "append" { + return false + } + return true + } + + for _, ssafn := range j.Program.InitialFunctions { + for _, block := range ssafn.Blocks { + for _, ins := range block.Instrs { + val, ok := ins.(ssa.Value) + if !ok || !isAppend(val) { + continue + } + + isUsed := false + visited := map[ssa.Instruction]bool{} + var walkRefs func(refs []ssa.Instruction) + walkRefs = func(refs []ssa.Instruction) { + loop: + for _, ref := range refs { + if visited[ref] { + continue + } + visited[ref] = true + if _, ok := ref.(*ssa.DebugRef); ok { + continue + } + switch ref := ref.(type) { + case *ssa.Phi: + walkRefs(*ref.Referrers()) + case *ssa.Sigma: + walkRefs(*ref.Referrers()) + case ssa.Value: + if !isAppend(ref) { + isUsed = true + } else { + walkRefs(*ref.Referrers()) + } + case ssa.Instruction: + isUsed = true + break loop + } + } + } + refs := val.Referrers() + if refs == nil { + continue + } + walkRefs(*refs) + if !isUsed { + j.Errorf(ins, "this result of append is never used, except maybe in other appends") + } + } + } + } +} + +func (c *Checker) CheckConcurrentTesting(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + for _, block := range ssafn.Blocks { + for _, ins := range block.Instrs { + gostmt, ok := ins.(*ssa.Go) + if !ok { + continue + } + var fn *ssa.Function + switch val := gostmt.Call.Value.(type) { + case *ssa.Function: + fn = val + case *ssa.MakeClosure: + fn = val.Fn.(*ssa.Function) + default: + continue + } + if fn.Blocks == nil { + continue + } + for _, block := range fn.Blocks { + for _, ins := range block.Instrs { + call, ok := ins.(*ssa.Call) + if !ok { + continue + } + if call.Call.IsInvoke() { + continue + } + callee := call.Call.StaticCallee() + if callee == nil { + continue + } + recv := callee.Signature.Recv() + if recv == nil { + continue + } + if !IsType(recv.Type(), "*testing.common") { + continue + } + fn, ok := call.Call.StaticCallee().Object().(*types.Func) + if !ok { + continue + } + name := fn.Name() + switch name { + case "FailNow", "Fatal", "Fatalf", "SkipNow", "Skip", "Skipf": + default: + continue + } + j.Errorf(gostmt, "the goroutine calls T.%s, which must be called in the same goroutine as the test", name) + } + } + } + } + } +} + +func (c *Checker) CheckCyclicFinalizer(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + node := c.funcDescs.CallGraph.CreateNode(ssafn) + for _, edge := range node.Out { + if edge.Callee.Func.RelString(nil) != "runtime.SetFinalizer" { + continue + } + arg0 := edge.Site.Common().Args[Arg("runtime.SetFinalizer.obj")] + if iface, ok := arg0.(*ssa.MakeInterface); ok { + arg0 = iface.X + } + unop, ok := arg0.(*ssa.UnOp) + if !ok { + continue + } + v, ok := unop.X.(*ssa.Alloc) + if !ok { + continue + } + arg1 := edge.Site.Common().Args[Arg("runtime.SetFinalizer.finalizer")] + if iface, ok := arg1.(*ssa.MakeInterface); ok { + arg1 = iface.X + } + mc, ok := arg1.(*ssa.MakeClosure) + if !ok { + continue + } + for _, b := range mc.Bindings { + if b == v { + pos := j.Program.DisplayPosition(mc.Fn.Pos()) + j.Errorf(edge.Site, "the finalizer closes over the object, preventing the finalizer from ever running (at %s)", pos) + } + } + } + } +} + +func (c *Checker) CheckSliceOutOfBounds(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + for _, block := range ssafn.Blocks { + for _, ins := range block.Instrs { + ia, ok := ins.(*ssa.IndexAddr) + if !ok { + continue + } + if _, ok := ia.X.Type().Underlying().(*types.Slice); !ok { + continue + } + sr, ok1 := c.funcDescs.Get(ssafn).Ranges[ia.X].(vrp.SliceInterval) + idxr, ok2 := c.funcDescs.Get(ssafn).Ranges[ia.Index].(vrp.IntInterval) + if !ok1 || !ok2 || !sr.IsKnown() || !idxr.IsKnown() || sr.Length.Empty() || idxr.Empty() { + continue + } + if idxr.Lower.Cmp(sr.Length.Upper) >= 0 { + j.Errorf(ia, "index out of bounds") + } + } + } + } +} + +func (c *Checker) CheckDeferLock(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + for _, block := range ssafn.Blocks { + instrs := FilterDebug(block.Instrs) + if len(instrs) < 2 { + continue + } + for i, ins := range instrs[:len(instrs)-1] { + call, ok := ins.(*ssa.Call) + if !ok { + continue + } + if !IsCallTo(call.Common(), "(*sync.Mutex).Lock") && !IsCallTo(call.Common(), "(*sync.RWMutex).RLock") { + continue + } + nins, ok := instrs[i+1].(*ssa.Defer) + if !ok { + continue + } + if !IsCallTo(&nins.Call, "(*sync.Mutex).Lock") && !IsCallTo(&nins.Call, "(*sync.RWMutex).RLock") { + continue + } + if call.Common().Args[0] != nins.Call.Args[0] { + continue + } + name := shortCallName(call.Common()) + alt := "" + switch name { + case "Lock": + alt = "Unlock" + case "RLock": + alt = "RUnlock" + } + j.Errorf(nins, "deferring %s right after having locked already; did you mean to defer %s?", name, alt) + } + } + } +} + +func (c *Checker) CheckNaNComparison(j *lint.Job) { + isNaN := func(v ssa.Value) bool { + call, ok := v.(*ssa.Call) + if !ok { + return false + } + return IsCallTo(call.Common(), "math.NaN") + } + for _, ssafn := range j.Program.InitialFunctions { + for _, block := range ssafn.Blocks { + for _, ins := range block.Instrs { + ins, ok := ins.(*ssa.BinOp) + if !ok { + continue + } + if isNaN(ins.X) || isNaN(ins.Y) { + j.Errorf(ins, "no value is equal to NaN, not even NaN itself") + } + } + } + } +} + +func (c *Checker) CheckInfiniteRecursion(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + node := c.funcDescs.CallGraph.CreateNode(ssafn) + for _, edge := range node.Out { + if edge.Callee != node { + continue + } + if _, ok := edge.Site.(*ssa.Go); ok { + // Recursively spawning goroutines doesn't consume + // stack space infinitely, so don't flag it. + continue + } + + block := edge.Site.Block() + canReturn := false + for _, b := range ssafn.Blocks { + if block.Dominates(b) { + continue + } + if len(b.Instrs) == 0 { + continue + } + if _, ok := b.Instrs[len(b.Instrs)-1].(*ssa.Return); ok { + canReturn = true + break + } + } + if canReturn { + continue + } + j.Errorf(edge.Site, "infinite recursive call") + } + } +} + +func objectName(obj types.Object) string { + if obj == nil { + return "" + } + var name string + if obj.Pkg() != nil && obj.Pkg().Scope().Lookup(obj.Name()) == obj { + s := obj.Pkg().Path() + if s != "" { + name += s + "." + } + } + name += obj.Name() + return name +} + +func isName(j *lint.Job, expr ast.Expr, name string) bool { + var obj types.Object + switch expr := expr.(type) { + case *ast.Ident: + obj = ObjectOf(j, expr) + case *ast.SelectorExpr: + obj = ObjectOf(j, expr.Sel) + } + return objectName(obj) == name +} + +func (c *Checker) CheckLeakyTimeTick(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + if IsInMain(j, ssafn) || IsInTest(j, ssafn) { + continue + } + for _, block := range ssafn.Blocks { + for _, ins := range block.Instrs { + call, ok := ins.(*ssa.Call) + if !ok || !IsCallTo(call.Common(), "time.Tick") { + continue + } + if c.funcDescs.Get(call.Parent()).Infinite { + continue + } + j.Errorf(call, "using time.Tick leaks the underlying ticker, consider using it only in endless functions, tests and the main package, and use time.NewTicker here") + } + } + } +} + +func (c *Checker) CheckDoubleNegation(j *lint.Job) { + fn := func(node ast.Node) bool { + unary1, ok := node.(*ast.UnaryExpr) + if !ok { + return true + } + unary2, ok := unary1.X.(*ast.UnaryExpr) + if !ok { + return true + } + if unary1.Op != token.NOT || unary2.Op != token.NOT { + return true + } + j.Errorf(unary1, "negating a boolean twice has no effect; is this a typo?") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func hasSideEffects(node ast.Node) bool { + dynamic := false + ast.Inspect(node, func(node ast.Node) bool { + switch node := node.(type) { + case *ast.CallExpr: + dynamic = true + return false + case *ast.UnaryExpr: + if node.Op == token.ARROW { + dynamic = true + return false + } + } + return true + }) + return dynamic +} + +func (c *Checker) CheckRepeatedIfElse(j *lint.Job) { + seen := map[ast.Node]bool{} + + var collectConds func(ifstmt *ast.IfStmt, inits []ast.Stmt, conds []ast.Expr) ([]ast.Stmt, []ast.Expr) + collectConds = func(ifstmt *ast.IfStmt, inits []ast.Stmt, conds []ast.Expr) ([]ast.Stmt, []ast.Expr) { + seen[ifstmt] = true + if ifstmt.Init != nil { + inits = append(inits, ifstmt.Init) + } + conds = append(conds, ifstmt.Cond) + if elsestmt, ok := ifstmt.Else.(*ast.IfStmt); ok { + return collectConds(elsestmt, inits, conds) + } + return inits, conds + } + fn := func(node ast.Node) bool { + ifstmt, ok := node.(*ast.IfStmt) + if !ok { + return true + } + if seen[ifstmt] { + return true + } + inits, conds := collectConds(ifstmt, nil, nil) + if len(inits) > 0 { + return true + } + for _, cond := range conds { + if hasSideEffects(cond) { + return true + } + } + counts := map[string]int{} + for _, cond := range conds { + s := Render(j, cond) + counts[s]++ + if counts[s] == 2 { + j.Errorf(cond, "this condition occurs multiple times in this if/else if chain") + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckSillyBitwiseOps(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + for _, block := range ssafn.Blocks { + for _, ins := range block.Instrs { + ins, ok := ins.(*ssa.BinOp) + if !ok { + continue + } + + if c, ok := ins.Y.(*ssa.Const); !ok || c.Value == nil || c.Value.Kind() != constant.Int || c.Uint64() != 0 { + continue + } + switch ins.Op { + case token.AND, token.OR, token.XOR: + default: + // we do not flag shifts because too often, x<<0 is part + // of a pattern, x<<0, x<<8, x<<16, ... + continue + } + path, _ := astutil.PathEnclosingInterval(j.File(ins), ins.Pos(), ins.Pos()) + if len(path) == 0 { + continue + } + if node, ok := path[0].(*ast.BinaryExpr); !ok || !IsZero(node.Y) { + continue + } + + switch ins.Op { + case token.AND: + j.Errorf(ins, "x & 0 always equals 0") + case token.OR, token.XOR: + j.Errorf(ins, "x %s 0 always equals x", ins.Op) + } + } + } + } +} + +func (c *Checker) CheckNonOctalFileMode(j *lint.Job) { + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + sig, ok := TypeOf(j, call.Fun).(*types.Signature) + if !ok { + return true + } + n := sig.Params().Len() + var args []int + for i := 0; i < n; i++ { + typ := sig.Params().At(i).Type() + if IsType(typ, "os.FileMode") { + args = append(args, i) + } + } + for _, i := range args { + lit, ok := call.Args[i].(*ast.BasicLit) + if !ok { + continue + } + if len(lit.Value) == 3 && + lit.Value[0] != '0' && + lit.Value[0] >= '0' && lit.Value[0] <= '7' && + lit.Value[1] >= '0' && lit.Value[1] <= '7' && + lit.Value[2] >= '0' && lit.Value[2] <= '7' { + + v, err := strconv.ParseInt(lit.Value, 10, 64) + if err != nil { + continue + } + j.Errorf(call.Args[i], "file mode '%s' evaluates to %#o; did you mean '0%s'?", lit.Value, v, lit.Value) + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckPureFunctions(j *lint.Job) { +fnLoop: + for _, ssafn := range j.Program.InitialFunctions { + if IsInTest(j, ssafn) { + params := ssafn.Signature.Params() + for i := 0; i < params.Len(); i++ { + param := params.At(i) + if IsType(param.Type(), "*testing.B") { + // Ignore discarded pure functions in code related + // to benchmarks. Instead of matching BenchmarkFoo + // functions, we match any function accepting a + // *testing.B. Benchmarks sometimes call generic + // functions for doing the actual work, and + // checking for the parameter is a lot easier and + // faster than analyzing call trees. + continue fnLoop + } + } + } + + for _, b := range ssafn.Blocks { + for _, ins := range b.Instrs { + ins, ok := ins.(*ssa.Call) + if !ok { + continue + } + refs := ins.Referrers() + if refs == nil || len(FilterDebug(*refs)) > 0 { + continue + } + callee := ins.Common().StaticCallee() + if callee == nil { + continue + } + if c.funcDescs.Get(callee).Pure && !c.funcDescs.Get(callee).Stub { + j.Errorf(ins, "%s is a pure function but its return value is ignored", callee.Name()) + continue + } + } + } + } +} + +func (c *Checker) isDeprecated(j *lint.Job, ident *ast.Ident) (bool, string) { + obj := ObjectOf(j, ident) + if obj.Pkg() == nil { + return false, "" + } + alt := c.deprecatedObjs[obj] + return alt != "", alt +} + +func (c *Checker) CheckDeprecated(j *lint.Job) { + // Selectors can appear outside of function literals, e.g. when + // declaring package level variables. + + var ssafn *ssa.Function + stack := 0 + fn := func(node ast.Node) bool { + if node == nil { + stack-- + } else { + stack++ + } + if stack == 1 { + ssafn = nil + } + if fn, ok := node.(*ast.FuncDecl); ok { + ssafn = j.Program.SSA.FuncValue(ObjectOf(j, fn.Name).(*types.Func)) + } + sel, ok := node.(*ast.SelectorExpr) + if !ok { + return true + } + + obj := ObjectOf(j, sel.Sel) + if obj.Pkg() == nil { + return true + } + nodePkg := j.NodePackage(node).Types + if nodePkg == obj.Pkg() || obj.Pkg().Path()+"_test" == nodePkg.Path() { + // Don't flag stuff in our own package + return true + } + if ok, alt := c.isDeprecated(j, sel.Sel); ok { + // Look for the first available alternative, not the first + // version something was deprecated in. If a function was + // deprecated in Go 1.6, an alternative has been available + // already in 1.0, and we're targeting 1.2, it still + // makes sense to use the alternative from 1.0, to be + // future-proof. + minVersion := deprecated.Stdlib[SelectorName(j, sel)].AlternativeAvailableSince + if !IsGoVersion(j, minVersion) { + return true + } + + if ssafn != nil { + if _, ok := c.deprecatedObjs[ssafn.Object()]; ok { + // functions that are deprecated may use deprecated + // symbols + return true + } + } + j.Errorf(sel, "%s is deprecated: %s", Render(j, sel), alt) + return true + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) callChecker(rules map[string]CallCheck) func(j *lint.Job) { + return func(j *lint.Job) { + c.checkCalls(j, rules) + } +} + +func (c *Checker) checkCalls(j *lint.Job, rules map[string]CallCheck) { + for _, ssafn := range j.Program.InitialFunctions { + node := c.funcDescs.CallGraph.CreateNode(ssafn) + for _, edge := range node.Out { + callee := edge.Callee.Func + obj, ok := callee.Object().(*types.Func) + if !ok { + continue + } + + r, ok := rules[obj.FullName()] + if !ok { + continue + } + var args []*Argument + ssaargs := edge.Site.Common().Args + if callee.Signature.Recv() != nil { + ssaargs = ssaargs[1:] + } + for _, arg := range ssaargs { + if iarg, ok := arg.(*ssa.MakeInterface); ok { + arg = iarg.X + } + vr := c.funcDescs.Get(edge.Site.Parent()).Ranges[arg] + args = append(args, &Argument{Value: Value{arg, vr}}) + } + call := &Call{ + Job: j, + Instr: edge.Site, + Args: args, + Checker: c, + Parent: edge.Site.Parent(), + } + r(call) + for idx, arg := range call.Args { + _ = idx + for _, e := range arg.invalids { + // path, _ := astutil.PathEnclosingInterval(f.File, edge.Site.Pos(), edge.Site.Pos()) + // if len(path) < 2 { + // continue + // } + // astcall, ok := path[0].(*ast.CallExpr) + // if !ok { + // continue + // } + // j.Errorf(astcall.Args[idx], "%s", e) + + j.Errorf(edge.Site, "%s", e) + } + } + for _, e := range call.invalids { + j.Errorf(call.Instr.Common(), "%s", e) + } + } + } +} + +func shortCallName(call *ssa.CallCommon) string { + if call.IsInvoke() { + return "" + } + switch v := call.Value.(type) { + case *ssa.Function: + fn, ok := v.Object().(*types.Func) + if !ok { + return "" + } + return fn.Name() + case *ssa.Builtin: + return v.Name() + } + return "" +} + +func (c *Checker) CheckWriterBufferModified(j *lint.Job) { + // TODO(dh): this might be a good candidate for taint analysis. + // Taint the argument as MUST_NOT_MODIFY, then propagate that + // through functions like bytes.Split + + for _, ssafn := range j.Program.InitialFunctions { + sig := ssafn.Signature + if ssafn.Name() != "Write" || sig.Recv() == nil || sig.Params().Len() != 1 || sig.Results().Len() != 2 { + continue + } + tArg, ok := sig.Params().At(0).Type().(*types.Slice) + if !ok { + continue + } + if basic, ok := tArg.Elem().(*types.Basic); !ok || basic.Kind() != types.Byte { + continue + } + if basic, ok := sig.Results().At(0).Type().(*types.Basic); !ok || basic.Kind() != types.Int { + continue + } + if named, ok := sig.Results().At(1).Type().(*types.Named); !ok || !IsType(named, "error") { + continue + } + + for _, block := range ssafn.Blocks { + for _, ins := range block.Instrs { + switch ins := ins.(type) { + case *ssa.Store: + addr, ok := ins.Addr.(*ssa.IndexAddr) + if !ok { + continue + } + if addr.X != ssafn.Params[1] { + continue + } + j.Errorf(ins, "io.Writer.Write must not modify the provided buffer, not even temporarily") + case *ssa.Call: + if !IsCallTo(ins.Common(), "append") { + continue + } + if ins.Common().Args[0] != ssafn.Params[1] { + continue + } + j.Errorf(ins, "io.Writer.Write must not modify the provided buffer, not even temporarily") + } + } + } + } +} + +func loopedRegexp(name string) CallCheck { + return func(call *Call) { + if len(extractConsts(call.Args[0].Value.Value)) == 0 { + return + } + if !call.Checker.isInLoop(call.Instr.Block()) { + return + } + call.Invalid(fmt.Sprintf("calling %s in a loop has poor performance, consider using regexp.Compile", name)) + } +} + +func (c *Checker) CheckEmptyBranch(j *lint.Job) { + for _, ssafn := range j.Program.InitialFunctions { + if ssafn.Syntax() == nil { + continue + } + if IsGenerated(j.File(ssafn.Syntax())) { + continue + } + if IsExample(ssafn) { + continue + } + fn := func(node ast.Node) bool { + ifstmt, ok := node.(*ast.IfStmt) + if !ok { + return true + } + if ifstmt.Else != nil { + b, ok := ifstmt.Else.(*ast.BlockStmt) + if !ok || len(b.List) != 0 { + return true + } + j.Errorf(ifstmt.Else, "empty branch") + } + if len(ifstmt.Body.List) != 0 { + return true + } + j.Errorf(ifstmt, "empty branch") + return true + } + Inspect(ssafn.Syntax(), fn) + } +} + +func (c *Checker) CheckMapBytesKey(j *lint.Job) { + for _, fn := range j.Program.InitialFunctions { + for _, b := range fn.Blocks { + insLoop: + for _, ins := range b.Instrs { + // find []byte -> string conversions + conv, ok := ins.(*ssa.Convert) + if !ok || conv.Type() != types.Universe.Lookup("string").Type() { + continue + } + if s, ok := conv.X.Type().(*types.Slice); !ok || s.Elem() != types.Universe.Lookup("byte").Type() { + continue + } + refs := conv.Referrers() + // need at least two (DebugRef) references: the + // conversion and the *ast.Ident + if refs == nil || len(*refs) < 2 { + continue + } + ident := false + // skip first reference, that's the conversion itself + for _, ref := range (*refs)[1:] { + switch ref := ref.(type) { + case *ssa.DebugRef: + if _, ok := ref.Expr.(*ast.Ident); !ok { + // the string seems to be used somewhere + // unexpected; the default branch should + // catch this already, but be safe + continue insLoop + } else { + ident = true + } + case *ssa.Lookup: + default: + // the string is used somewhere else than a + // map lookup + continue insLoop + } + } + + // the result of the conversion wasn't assigned to an + // identifier + if !ident { + continue + } + j.Errorf(conv, "m[string(key)] would be more efficient than k := string(key); m[k]") + } + } + } +} + +func (c *Checker) CheckRangeStringRunes(j *lint.Job) { + sharedcheck.CheckRangeStringRunes(j) +} + +func (c *Checker) CheckSelfAssignment(j *lint.Job) { + fn := func(node ast.Node) bool { + assign, ok := node.(*ast.AssignStmt) + if !ok { + return true + } + if assign.Tok != token.ASSIGN || len(assign.Lhs) != len(assign.Rhs) { + return true + } + for i, stmt := range assign.Lhs { + rlh := Render(j, stmt) + rrh := Render(j, assign.Rhs[i]) + if rlh == rrh { + j.Errorf(assign, "self-assignment of %s to %s", rrh, rlh) + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func buildTagsIdentical(s1, s2 []string) bool { + if len(s1) != len(s2) { + return false + } + s1s := make([]string, len(s1)) + copy(s1s, s1) + sort.Strings(s1s) + s2s := make([]string, len(s2)) + copy(s2s, s2) + sort.Strings(s2s) + for i, s := range s1s { + if s != s2s[i] { + return false + } + } + return true +} + +func (c *Checker) CheckDuplicateBuildConstraints(job *lint.Job) { + for _, f := range job.Program.Files { + constraints := buildTags(f) + for i, constraint1 := range constraints { + for j, constraint2 := range constraints { + if i >= j { + continue + } + if buildTagsIdentical(constraint1, constraint2) { + job.Errorf(f, "identical build constraints %q and %q", + strings.Join(constraint1, " "), + strings.Join(constraint2, " ")) + } + } + } + } +} + +func (c *Checker) CheckSillyRegexp(j *lint.Job) { + // We could use the rule checking engine for this, but the + // arguments aren't really invalid. + for _, fn := range j.Program.InitialFunctions { + for _, b := range fn.Blocks { + for _, ins := range b.Instrs { + call, ok := ins.(*ssa.Call) + if !ok { + continue + } + switch CallName(call.Common()) { + case "regexp.MustCompile", "regexp.Compile", "regexp.Match", "regexp.MatchReader", "regexp.MatchString": + default: + continue + } + c, ok := call.Common().Args[0].(*ssa.Const) + if !ok { + continue + } + s := constant.StringVal(c.Value) + re, err := syntax.Parse(s, 0) + if err != nil { + continue + } + if re.Op != syntax.OpLiteral && re.Op != syntax.OpEmptyMatch { + continue + } + j.Errorf(call, "regular expression does not contain any meta characters") + } + } + } +} + +func (c *Checker) CheckMissingEnumTypesInDeclaration(j *lint.Job) { + fn := func(node ast.Node) bool { + decl, ok := node.(*ast.GenDecl) + if !ok { + return true + } + if !decl.Lparen.IsValid() { + // not a parenthesised gendecl + // + // TODO(dh): do we need this check, considering we require + // decl.Specs to contain 2+ elements? + return true + } + if decl.Tok != token.CONST { + return true + } + if len(decl.Specs) < 2 { + return true + } + if decl.Specs[0].(*ast.ValueSpec).Type == nil { + // first constant doesn't have a type + return true + } + for i, spec := range decl.Specs { + spec := spec.(*ast.ValueSpec) + if len(spec.Names) != 1 || len(spec.Values) != 1 { + return true + } + switch v := spec.Values[0].(type) { + case *ast.BasicLit: + case *ast.UnaryExpr: + if _, ok := v.X.(*ast.BasicLit); !ok { + return true + } + default: + // if it's not a literal it might be typed, such as + // time.Microsecond = 1000 * Nanosecond + return true + } + if i == 0 { + continue + } + if spec.Type != nil { + return true + } + } + j.Errorf(decl, "only the first constant has an explicit type") + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckTimerResetReturnValue(j *lint.Job) { + for _, fn := range j.Program.InitialFunctions { + for _, block := range fn.Blocks { + for _, ins := range block.Instrs { + call, ok := ins.(*ssa.Call) + if !ok { + continue + } + if !IsCallTo(call.Common(), "(*time.Timer).Reset") { + continue + } + refs := call.Referrers() + if refs == nil { + continue + } + for _, ref := range FilterDebug(*refs) { + ifstmt, ok := ref.(*ssa.If) + if !ok { + continue + } + + found := false + for _, succ := range ifstmt.Block().Succs { + if len(succ.Preds) != 1 { + // Merge point, not a branch in the + // syntactical sense. + + // FIXME(dh): this is broken for if + // statements a la "if x || y" + continue + } + ssautil.Walk(succ, func(b *ssa.BasicBlock) bool { + if !succ.Dominates(b) { + // We've reached the end of the branch + return false + } + for _, ins := range b.Instrs { + // TODO(dh): we should check that + // we're receiving from the channel of + // a time.Timer to further reduce + // false positives. Not a key + // priority, considering the rarity of + // Reset and the tiny likeliness of a + // false positive + if ins, ok := ins.(*ssa.UnOp); ok && ins.Op == token.ARROW && IsType(ins.X.Type(), "<-chan time.Time") { + found = true + return false + } + } + return true + }) + } + + if found { + j.Errorf(call, "it is not possible to use Reset's return value correctly, as there is a race condition between draining the channel and the new timer expiring") + } + } + } + } + } +} diff --git a/vendor/honnef.co/go/tools/staticcheck/rules.go b/vendor/honnef.co/go/tools/staticcheck/rules.go new file mode 100644 index 0000000000..d6af573c21 --- /dev/null +++ b/vendor/honnef.co/go/tools/staticcheck/rules.go @@ -0,0 +1,322 @@ +package staticcheck + +import ( + "fmt" + "go/constant" + "go/types" + "net" + "net/url" + "regexp" + "sort" + "strconv" + "strings" + "time" + "unicode/utf8" + + "honnef.co/go/tools/lint" + . "honnef.co/go/tools/lint/lintdsl" + "honnef.co/go/tools/ssa" + "honnef.co/go/tools/staticcheck/vrp" +) + +const ( + MsgInvalidHostPort = "invalid port or service name in host:port pair" + MsgInvalidUTF8 = "argument is not a valid UTF-8 encoded string" + MsgNonUniqueCutset = "cutset contains duplicate characters" +) + +type Call struct { + Job *lint.Job + Instr ssa.CallInstruction + Args []*Argument + + Checker *Checker + Parent *ssa.Function + + invalids []string +} + +func (c *Call) Invalid(msg string) { + c.invalids = append(c.invalids, msg) +} + +type Argument struct { + Value Value + invalids []string +} + +func (arg *Argument) Invalid(msg string) { + arg.invalids = append(arg.invalids, msg) +} + +type Value struct { + Value ssa.Value + Range vrp.Range +} + +type CallCheck func(call *Call) + +func extractConsts(v ssa.Value) []*ssa.Const { + switch v := v.(type) { + case *ssa.Const: + return []*ssa.Const{v} + case *ssa.MakeInterface: + return extractConsts(v.X) + default: + return nil + } +} + +func ValidateRegexp(v Value) error { + for _, c := range extractConsts(v.Value) { + if c.Value == nil { + continue + } + if c.Value.Kind() != constant.String { + continue + } + s := constant.StringVal(c.Value) + if _, err := regexp.Compile(s); err != nil { + return err + } + } + return nil +} + +func ValidateTimeLayout(v Value) error { + for _, c := range extractConsts(v.Value) { + if c.Value == nil { + continue + } + if c.Value.Kind() != constant.String { + continue + } + s := constant.StringVal(c.Value) + s = strings.Replace(s, "_", " ", -1) + s = strings.Replace(s, "Z", "-", -1) + _, err := time.Parse(s, s) + if err != nil { + return err + } + } + return nil +} + +func ValidateURL(v Value) error { + for _, c := range extractConsts(v.Value) { + if c.Value == nil { + continue + } + if c.Value.Kind() != constant.String { + continue + } + s := constant.StringVal(c.Value) + _, err := url.Parse(s) + if err != nil { + return fmt.Errorf("%q is not a valid URL: %s", s, err) + } + } + return nil +} + +func IntValue(v Value, z vrp.Z) bool { + r, ok := v.Range.(vrp.IntInterval) + if !ok || !r.IsKnown() { + return false + } + if r.Lower != r.Upper { + return false + } + if r.Lower.Cmp(z) == 0 { + return true + } + return false +} + +func InvalidUTF8(v Value) bool { + for _, c := range extractConsts(v.Value) { + if c.Value == nil { + continue + } + if c.Value.Kind() != constant.String { + continue + } + s := constant.StringVal(c.Value) + if !utf8.ValidString(s) { + return true + } + } + return false +} + +func UnbufferedChannel(v Value) bool { + r, ok := v.Range.(vrp.ChannelInterval) + if !ok || !r.IsKnown() { + return false + } + if r.Size.Lower.Cmp(vrp.NewZ(0)) == 0 && + r.Size.Upper.Cmp(vrp.NewZ(0)) == 0 { + return true + } + return false +} + +func Pointer(v Value) bool { + switch v.Value.Type().Underlying().(type) { + case *types.Pointer, *types.Interface: + return true + } + return false +} + +func ConvertedFromInt(v Value) bool { + conv, ok := v.Value.(*ssa.Convert) + if !ok { + return false + } + b, ok := conv.X.Type().Underlying().(*types.Basic) + if !ok { + return false + } + if (b.Info() & types.IsInteger) == 0 { + return false + } + return true +} + +func validEncodingBinaryType(j *lint.Job, typ types.Type) bool { + typ = typ.Underlying() + switch typ := typ.(type) { + case *types.Basic: + switch typ.Kind() { + case types.Uint8, types.Uint16, types.Uint32, types.Uint64, + types.Int8, types.Int16, types.Int32, types.Int64, + types.Float32, types.Float64, types.Complex64, types.Complex128, types.Invalid: + return true + case types.Bool: + return IsGoVersion(j, 8) + } + return false + case *types.Struct: + n := typ.NumFields() + for i := 0; i < n; i++ { + if !validEncodingBinaryType(j, typ.Field(i).Type()) { + return false + } + } + return true + case *types.Array: + return validEncodingBinaryType(j, typ.Elem()) + case *types.Interface: + // we can't determine if it's a valid type or not + return true + } + return false +} + +func CanBinaryMarshal(j *lint.Job, v Value) bool { + typ := v.Value.Type().Underlying() + if ttyp, ok := typ.(*types.Pointer); ok { + typ = ttyp.Elem().Underlying() + } + if ttyp, ok := typ.(interface { + Elem() types.Type + }); ok { + if _, ok := ttyp.(*types.Pointer); !ok { + typ = ttyp.Elem() + } + } + + return validEncodingBinaryType(j, typ) +} + +func RepeatZeroTimes(name string, arg int) CallCheck { + return func(call *Call) { + arg := call.Args[arg] + if IntValue(arg.Value, vrp.NewZ(0)) { + arg.Invalid(fmt.Sprintf("calling %s with n == 0 will return no results, did you mean -1?", name)) + } + } +} + +func validateServiceName(s string) bool { + if len(s) < 1 || len(s) > 15 { + return false + } + if s[0] == '-' || s[len(s)-1] == '-' { + return false + } + if strings.Contains(s, "--") { + return false + } + hasLetter := false + for _, r := range s { + if (r >= 'A' && r <= 'Z') || (r >= 'a' && r <= 'z') { + hasLetter = true + continue + } + if r >= '0' && r <= '9' { + continue + } + return false + } + return hasLetter +} + +func validatePort(s string) bool { + n, err := strconv.ParseInt(s, 10, 64) + if err != nil { + return validateServiceName(s) + } + return n >= 0 && n <= 65535 +} + +func ValidHostPort(v Value) bool { + for _, k := range extractConsts(v.Value) { + if k.Value == nil { + continue + } + if k.Value.Kind() != constant.String { + continue + } + s := constant.StringVal(k.Value) + _, port, err := net.SplitHostPort(s) + if err != nil { + return false + } + // TODO(dh): check hostname + if !validatePort(port) { + return false + } + } + return true +} + +// ConvertedFrom reports whether value v was converted from type typ. +func ConvertedFrom(v Value, typ string) bool { + change, ok := v.Value.(*ssa.ChangeType) + return ok && IsType(change.X.Type(), typ) +} + +func UniqueStringCutset(v Value) bool { + for _, c := range extractConsts(v.Value) { + if c.Value == nil { + continue + } + if c.Value.Kind() != constant.String { + continue + } + s := constant.StringVal(c.Value) + rs := runeSlice(s) + if len(rs) < 2 { + continue + } + sort.Sort(rs) + for i, r := range rs[1:] { + if rs[i] == r { + return false + } + } + } + return true +} diff --git a/vendor/honnef.co/go/tools/staticcheck/vrp/channel.go b/vendor/honnef.co/go/tools/staticcheck/vrp/channel.go new file mode 100644 index 0000000000..0ef73787ba --- /dev/null +++ b/vendor/honnef.co/go/tools/staticcheck/vrp/channel.go @@ -0,0 +1,73 @@ +package vrp + +import ( + "fmt" + + "honnef.co/go/tools/ssa" +) + +type ChannelInterval struct { + Size IntInterval +} + +func (c ChannelInterval) Union(other Range) Range { + i, ok := other.(ChannelInterval) + if !ok { + i = ChannelInterval{EmptyIntInterval} + } + if c.Size.Empty() || !c.Size.IsKnown() { + return i + } + if i.Size.Empty() || !i.Size.IsKnown() { + return c + } + return ChannelInterval{ + Size: c.Size.Union(i.Size).(IntInterval), + } +} + +func (c ChannelInterval) String() string { + return c.Size.String() +} + +func (c ChannelInterval) IsKnown() bool { + return c.Size.IsKnown() +} + +type MakeChannelConstraint struct { + aConstraint + Buffer ssa.Value +} +type ChannelChangeTypeConstraint struct { + aConstraint + X ssa.Value +} + +func NewMakeChannelConstraint(buffer, y ssa.Value) Constraint { + return &MakeChannelConstraint{NewConstraint(y), buffer} +} +func NewChannelChangeTypeConstraint(x, y ssa.Value) Constraint { + return &ChannelChangeTypeConstraint{NewConstraint(y), x} +} + +func (c *MakeChannelConstraint) Operands() []ssa.Value { return []ssa.Value{c.Buffer} } +func (c *ChannelChangeTypeConstraint) Operands() []ssa.Value { return []ssa.Value{c.X} } + +func (c *MakeChannelConstraint) String() string { + return fmt.Sprintf("%s = make(chan, %s)", c.Y().Name(), c.Buffer.Name()) +} +func (c *ChannelChangeTypeConstraint) String() string { + return fmt.Sprintf("%s = changetype(%s)", c.Y().Name(), c.X.Name()) +} + +func (c *MakeChannelConstraint) Eval(g *Graph) Range { + i, ok := g.Range(c.Buffer).(IntInterval) + if !ok { + return ChannelInterval{NewIntInterval(NewZ(0), PInfinity)} + } + if i.Lower.Sign() == -1 { + i.Lower = NewZ(0) + } + return ChannelInterval{i} +} +func (c *ChannelChangeTypeConstraint) Eval(g *Graph) Range { return g.Range(c.X) } diff --git a/vendor/honnef.co/go/tools/staticcheck/vrp/int.go b/vendor/honnef.co/go/tools/staticcheck/vrp/int.go new file mode 100644 index 0000000000..926bb7af3d --- /dev/null +++ b/vendor/honnef.co/go/tools/staticcheck/vrp/int.go @@ -0,0 +1,476 @@ +package vrp + +import ( + "fmt" + "go/token" + "go/types" + "math/big" + + "honnef.co/go/tools/ssa" +) + +type Zs []Z + +func (zs Zs) Len() int { + return len(zs) +} + +func (zs Zs) Less(i int, j int) bool { + return zs[i].Cmp(zs[j]) == -1 +} + +func (zs Zs) Swap(i int, j int) { + zs[i], zs[j] = zs[j], zs[i] +} + +type Z struct { + infinity int8 + integer *big.Int +} + +func NewZ(n int64) Z { + return NewBigZ(big.NewInt(n)) +} + +func NewBigZ(n *big.Int) Z { + return Z{integer: n} +} + +func (z1 Z) Infinite() bool { + return z1.infinity != 0 +} + +func (z1 Z) Add(z2 Z) Z { + if z2.Sign() == -1 { + return z1.Sub(z2.Negate()) + } + if z1 == NInfinity { + return NInfinity + } + if z1 == PInfinity { + return PInfinity + } + if z2 == PInfinity { + return PInfinity + } + + if !z1.Infinite() && !z2.Infinite() { + n := &big.Int{} + n.Add(z1.integer, z2.integer) + return NewBigZ(n) + } + + panic(fmt.Sprintf("%s + %s is not defined", z1, z2)) +} + +func (z1 Z) Sub(z2 Z) Z { + if z2.Sign() == -1 { + return z1.Add(z2.Negate()) + } + if !z1.Infinite() && !z2.Infinite() { + n := &big.Int{} + n.Sub(z1.integer, z2.integer) + return NewBigZ(n) + } + + if z1 != PInfinity && z2 == PInfinity { + return NInfinity + } + if z1.Infinite() && !z2.Infinite() { + return Z{infinity: z1.infinity} + } + if z1 == PInfinity && z2 == PInfinity { + return PInfinity + } + panic(fmt.Sprintf("%s - %s is not defined", z1, z2)) +} + +func (z1 Z) Mul(z2 Z) Z { + if (z1.integer != nil && z1.integer.Sign() == 0) || + (z2.integer != nil && z2.integer.Sign() == 0) { + return NewBigZ(&big.Int{}) + } + + if z1.infinity != 0 || z2.infinity != 0 { + return Z{infinity: int8(z1.Sign() * z2.Sign())} + } + + n := &big.Int{} + n.Mul(z1.integer, z2.integer) + return NewBigZ(n) +} + +func (z1 Z) Negate() Z { + if z1.infinity == 1 { + return NInfinity + } + if z1.infinity == -1 { + return PInfinity + } + n := &big.Int{} + n.Neg(z1.integer) + return NewBigZ(n) +} + +func (z1 Z) Sign() int { + if z1.infinity != 0 { + return int(z1.infinity) + } + return z1.integer.Sign() +} + +func (z1 Z) String() string { + if z1 == NInfinity { + return "-∞" + } + if z1 == PInfinity { + return "∞" + } + return fmt.Sprintf("%d", z1.integer) +} + +func (z1 Z) Cmp(z2 Z) int { + if z1.infinity == z2.infinity && z1.infinity != 0 { + return 0 + } + if z1 == PInfinity { + return 1 + } + if z1 == NInfinity { + return -1 + } + if z2 == NInfinity { + return 1 + } + if z2 == PInfinity { + return -1 + } + return z1.integer.Cmp(z2.integer) +} + +func MaxZ(zs ...Z) Z { + if len(zs) == 0 { + panic("Max called with no arguments") + } + if len(zs) == 1 { + return zs[0] + } + ret := zs[0] + for _, z := range zs[1:] { + if z.Cmp(ret) == 1 { + ret = z + } + } + return ret +} + +func MinZ(zs ...Z) Z { + if len(zs) == 0 { + panic("Min called with no arguments") + } + if len(zs) == 1 { + return zs[0] + } + ret := zs[0] + for _, z := range zs[1:] { + if z.Cmp(ret) == -1 { + ret = z + } + } + return ret +} + +var NInfinity = Z{infinity: -1} +var PInfinity = Z{infinity: 1} +var EmptyIntInterval = IntInterval{true, PInfinity, NInfinity} + +func InfinityFor(v ssa.Value) IntInterval { + if b, ok := v.Type().Underlying().(*types.Basic); ok { + if (b.Info() & types.IsUnsigned) != 0 { + return NewIntInterval(NewZ(0), PInfinity) + } + } + return NewIntInterval(NInfinity, PInfinity) +} + +type IntInterval struct { + known bool + Lower Z + Upper Z +} + +func NewIntInterval(l, u Z) IntInterval { + if u.Cmp(l) == -1 { + return EmptyIntInterval + } + return IntInterval{known: true, Lower: l, Upper: u} +} + +func (i IntInterval) IsKnown() bool { + return i.known +} + +func (i IntInterval) Empty() bool { + return i.Lower == PInfinity && i.Upper == NInfinity +} + +func (i IntInterval) IsMaxRange() bool { + return i.Lower == NInfinity && i.Upper == PInfinity +} + +func (i1 IntInterval) Intersection(i2 IntInterval) IntInterval { + if !i1.IsKnown() { + return i2 + } + if !i2.IsKnown() { + return i1 + } + if i1.Empty() || i2.Empty() { + return EmptyIntInterval + } + i3 := NewIntInterval(MaxZ(i1.Lower, i2.Lower), MinZ(i1.Upper, i2.Upper)) + if i3.Lower.Cmp(i3.Upper) == 1 { + return EmptyIntInterval + } + return i3 +} + +func (i1 IntInterval) Union(other Range) Range { + i2, ok := other.(IntInterval) + if !ok { + i2 = EmptyIntInterval + } + if i1.Empty() || !i1.IsKnown() { + return i2 + } + if i2.Empty() || !i2.IsKnown() { + return i1 + } + return NewIntInterval(MinZ(i1.Lower, i2.Lower), MaxZ(i1.Upper, i2.Upper)) +} + +func (i1 IntInterval) Add(i2 IntInterval) IntInterval { + if i1.Empty() || i2.Empty() { + return EmptyIntInterval + } + l1, u1, l2, u2 := i1.Lower, i1.Upper, i2.Lower, i2.Upper + return NewIntInterval(l1.Add(l2), u1.Add(u2)) +} + +func (i1 IntInterval) Sub(i2 IntInterval) IntInterval { + if i1.Empty() || i2.Empty() { + return EmptyIntInterval + } + l1, u1, l2, u2 := i1.Lower, i1.Upper, i2.Lower, i2.Upper + return NewIntInterval(l1.Sub(u2), u1.Sub(l2)) +} + +func (i1 IntInterval) Mul(i2 IntInterval) IntInterval { + if i1.Empty() || i2.Empty() { + return EmptyIntInterval + } + x1, x2 := i1.Lower, i1.Upper + y1, y2 := i2.Lower, i2.Upper + return NewIntInterval( + MinZ(x1.Mul(y1), x1.Mul(y2), x2.Mul(y1), x2.Mul(y2)), + MaxZ(x1.Mul(y1), x1.Mul(y2), x2.Mul(y1), x2.Mul(y2)), + ) +} + +func (i1 IntInterval) String() string { + if !i1.IsKnown() { + return "[⊥, ⊥]" + } + if i1.Empty() { + return "{}" + } + return fmt.Sprintf("[%s, %s]", i1.Lower, i1.Upper) +} + +type IntArithmeticConstraint struct { + aConstraint + A ssa.Value + B ssa.Value + Op token.Token + Fn func(IntInterval, IntInterval) IntInterval +} + +type IntAddConstraint struct{ *IntArithmeticConstraint } +type IntSubConstraint struct{ *IntArithmeticConstraint } +type IntMulConstraint struct{ *IntArithmeticConstraint } + +type IntConversionConstraint struct { + aConstraint + X ssa.Value +} + +type IntIntersectionConstraint struct { + aConstraint + ranges Ranges + A ssa.Value + B ssa.Value + Op token.Token + I IntInterval + resolved bool +} + +type IntIntervalConstraint struct { + aConstraint + I IntInterval +} + +func NewIntArithmeticConstraint(a, b, y ssa.Value, op token.Token, fn func(IntInterval, IntInterval) IntInterval) *IntArithmeticConstraint { + return &IntArithmeticConstraint{NewConstraint(y), a, b, op, fn} +} +func NewIntAddConstraint(a, b, y ssa.Value) Constraint { + return &IntAddConstraint{NewIntArithmeticConstraint(a, b, y, token.ADD, IntInterval.Add)} +} +func NewIntSubConstraint(a, b, y ssa.Value) Constraint { + return &IntSubConstraint{NewIntArithmeticConstraint(a, b, y, token.SUB, IntInterval.Sub)} +} +func NewIntMulConstraint(a, b, y ssa.Value) Constraint { + return &IntMulConstraint{NewIntArithmeticConstraint(a, b, y, token.MUL, IntInterval.Mul)} +} +func NewIntConversionConstraint(x, y ssa.Value) Constraint { + return &IntConversionConstraint{NewConstraint(y), x} +} +func NewIntIntersectionConstraint(a, b ssa.Value, op token.Token, ranges Ranges, y ssa.Value) Constraint { + return &IntIntersectionConstraint{ + aConstraint: NewConstraint(y), + ranges: ranges, + A: a, + B: b, + Op: op, + } +} +func NewIntIntervalConstraint(i IntInterval, y ssa.Value) Constraint { + return &IntIntervalConstraint{NewConstraint(y), i} +} + +func (c *IntArithmeticConstraint) Operands() []ssa.Value { return []ssa.Value{c.A, c.B} } +func (c *IntConversionConstraint) Operands() []ssa.Value { return []ssa.Value{c.X} } +func (c *IntIntersectionConstraint) Operands() []ssa.Value { return []ssa.Value{c.A} } +func (s *IntIntervalConstraint) Operands() []ssa.Value { return nil } + +func (c *IntArithmeticConstraint) String() string { + return fmt.Sprintf("%s = %s %s %s", c.Y().Name(), c.A.Name(), c.Op, c.B.Name()) +} +func (c *IntConversionConstraint) String() string { + return fmt.Sprintf("%s = %s(%s)", c.Y().Name(), c.Y().Type(), c.X.Name()) +} +func (c *IntIntersectionConstraint) String() string { + return fmt.Sprintf("%s = %s %s %s (%t branch)", c.Y().Name(), c.A.Name(), c.Op, c.B.Name(), c.Y().(*ssa.Sigma).Branch) +} +func (c *IntIntervalConstraint) String() string { return fmt.Sprintf("%s = %s", c.Y().Name(), c.I) } + +func (c *IntArithmeticConstraint) Eval(g *Graph) Range { + i1, i2 := g.Range(c.A).(IntInterval), g.Range(c.B).(IntInterval) + if !i1.IsKnown() || !i2.IsKnown() { + return IntInterval{} + } + return c.Fn(i1, i2) +} +func (c *IntConversionConstraint) Eval(g *Graph) Range { + s := &types.StdSizes{ + // XXX is it okay to assume the largest word size, or do we + // need to be platform specific? + WordSize: 8, + MaxAlign: 1, + } + fromI := g.Range(c.X).(IntInterval) + toI := g.Range(c.Y()).(IntInterval) + fromT := c.X.Type().Underlying().(*types.Basic) + toT := c.Y().Type().Underlying().(*types.Basic) + fromB := s.Sizeof(c.X.Type()) + toB := s.Sizeof(c.Y().Type()) + + if !fromI.IsKnown() { + return toI + } + if !toI.IsKnown() { + return fromI + } + + // uint -> sint/uint, M > N: [max(0, l1), min(2**N-1, u2)] + if (fromT.Info()&types.IsUnsigned != 0) && + toB > fromB { + + n := big.NewInt(1) + n.Lsh(n, uint(fromB*8)) + n.Sub(n, big.NewInt(1)) + return NewIntInterval( + MaxZ(NewZ(0), fromI.Lower), + MinZ(NewBigZ(n), toI.Upper), + ) + } + + // sint -> sint, M > N; [max(-∞, l1), min(2**N-1, u2)] + if (fromT.Info()&types.IsUnsigned == 0) && + (toT.Info()&types.IsUnsigned == 0) && + toB > fromB { + + n := big.NewInt(1) + n.Lsh(n, uint(fromB*8)) + n.Sub(n, big.NewInt(1)) + return NewIntInterval( + MaxZ(NInfinity, fromI.Lower), + MinZ(NewBigZ(n), toI.Upper), + ) + } + + return fromI +} +func (c *IntIntersectionConstraint) Eval(g *Graph) Range { + xi := g.Range(c.A).(IntInterval) + if !xi.IsKnown() { + return c.I + } + return xi.Intersection(c.I) +} +func (c *IntIntervalConstraint) Eval(*Graph) Range { return c.I } + +func (c *IntIntersectionConstraint) Futures() []ssa.Value { + return []ssa.Value{c.B} +} + +func (c *IntIntersectionConstraint) Resolve() { + r, ok := c.ranges[c.B].(IntInterval) + if !ok { + c.I = InfinityFor(c.Y()) + return + } + + switch c.Op { + case token.EQL: + c.I = r + case token.GTR: + c.I = NewIntInterval(r.Lower.Add(NewZ(1)), PInfinity) + case token.GEQ: + c.I = NewIntInterval(r.Lower, PInfinity) + case token.LSS: + // TODO(dh): do we need 0 instead of NInfinity for uints? + c.I = NewIntInterval(NInfinity, r.Upper.Sub(NewZ(1))) + case token.LEQ: + c.I = NewIntInterval(NInfinity, r.Upper) + case token.NEQ: + c.I = InfinityFor(c.Y()) + default: + panic("unsupported op " + c.Op.String()) + } +} + +func (c *IntIntersectionConstraint) IsKnown() bool { + return c.I.IsKnown() +} + +func (c *IntIntersectionConstraint) MarkUnresolved() { + c.resolved = false +} + +func (c *IntIntersectionConstraint) MarkResolved() { + c.resolved = true +} + +func (c *IntIntersectionConstraint) IsResolved() bool { + return c.resolved +} diff --git a/vendor/honnef.co/go/tools/staticcheck/vrp/slice.go b/vendor/honnef.co/go/tools/staticcheck/vrp/slice.go new file mode 100644 index 0000000000..40658dd8d8 --- /dev/null +++ b/vendor/honnef.co/go/tools/staticcheck/vrp/slice.go @@ -0,0 +1,273 @@ +package vrp + +// TODO(dh): most of the constraints have implementations identical to +// that of strings. Consider reusing them. + +import ( + "fmt" + "go/types" + + "honnef.co/go/tools/ssa" +) + +type SliceInterval struct { + Length IntInterval +} + +func (s SliceInterval) Union(other Range) Range { + i, ok := other.(SliceInterval) + if !ok { + i = SliceInterval{EmptyIntInterval} + } + if s.Length.Empty() || !s.Length.IsKnown() { + return i + } + if i.Length.Empty() || !i.Length.IsKnown() { + return s + } + return SliceInterval{ + Length: s.Length.Union(i.Length).(IntInterval), + } +} +func (s SliceInterval) String() string { return s.Length.String() } +func (s SliceInterval) IsKnown() bool { return s.Length.IsKnown() } + +type SliceAppendConstraint struct { + aConstraint + A ssa.Value + B ssa.Value +} + +type SliceSliceConstraint struct { + aConstraint + X ssa.Value + Lower ssa.Value + Upper ssa.Value +} + +type ArraySliceConstraint struct { + aConstraint + X ssa.Value + Lower ssa.Value + Upper ssa.Value +} + +type SliceIntersectionConstraint struct { + aConstraint + X ssa.Value + I IntInterval +} + +type SliceLengthConstraint struct { + aConstraint + X ssa.Value +} + +type MakeSliceConstraint struct { + aConstraint + Size ssa.Value +} + +type SliceIntervalConstraint struct { + aConstraint + I IntInterval +} + +func NewSliceAppendConstraint(a, b, y ssa.Value) Constraint { + return &SliceAppendConstraint{NewConstraint(y), a, b} +} +func NewSliceSliceConstraint(x, lower, upper, y ssa.Value) Constraint { + return &SliceSliceConstraint{NewConstraint(y), x, lower, upper} +} +func NewArraySliceConstraint(x, lower, upper, y ssa.Value) Constraint { + return &ArraySliceConstraint{NewConstraint(y), x, lower, upper} +} +func NewSliceIntersectionConstraint(x ssa.Value, i IntInterval, y ssa.Value) Constraint { + return &SliceIntersectionConstraint{NewConstraint(y), x, i} +} +func NewSliceLengthConstraint(x, y ssa.Value) Constraint { + return &SliceLengthConstraint{NewConstraint(y), x} +} +func NewMakeSliceConstraint(size, y ssa.Value) Constraint { + return &MakeSliceConstraint{NewConstraint(y), size} +} +func NewSliceIntervalConstraint(i IntInterval, y ssa.Value) Constraint { + return &SliceIntervalConstraint{NewConstraint(y), i} +} + +func (c *SliceAppendConstraint) Operands() []ssa.Value { return []ssa.Value{c.A, c.B} } +func (c *SliceSliceConstraint) Operands() []ssa.Value { + ops := []ssa.Value{c.X} + if c.Lower != nil { + ops = append(ops, c.Lower) + } + if c.Upper != nil { + ops = append(ops, c.Upper) + } + return ops +} +func (c *ArraySliceConstraint) Operands() []ssa.Value { + ops := []ssa.Value{c.X} + if c.Lower != nil { + ops = append(ops, c.Lower) + } + if c.Upper != nil { + ops = append(ops, c.Upper) + } + return ops +} +func (c *SliceIntersectionConstraint) Operands() []ssa.Value { return []ssa.Value{c.X} } +func (c *SliceLengthConstraint) Operands() []ssa.Value { return []ssa.Value{c.X} } +func (c *MakeSliceConstraint) Operands() []ssa.Value { return []ssa.Value{c.Size} } +func (s *SliceIntervalConstraint) Operands() []ssa.Value { return nil } + +func (c *SliceAppendConstraint) String() string { + return fmt.Sprintf("%s = append(%s, %s)", c.Y().Name(), c.A.Name(), c.B.Name()) +} +func (c *SliceSliceConstraint) String() string { + var lname, uname string + if c.Lower != nil { + lname = c.Lower.Name() + } + if c.Upper != nil { + uname = c.Upper.Name() + } + return fmt.Sprintf("%s[%s:%s]", c.X.Name(), lname, uname) +} +func (c *ArraySliceConstraint) String() string { + var lname, uname string + if c.Lower != nil { + lname = c.Lower.Name() + } + if c.Upper != nil { + uname = c.Upper.Name() + } + return fmt.Sprintf("%s[%s:%s]", c.X.Name(), lname, uname) +} +func (c *SliceIntersectionConstraint) String() string { + return fmt.Sprintf("%s = %s.%t ⊓ %s", c.Y().Name(), c.X.Name(), c.Y().(*ssa.Sigma).Branch, c.I) +} +func (c *SliceLengthConstraint) String() string { + return fmt.Sprintf("%s = len(%s)", c.Y().Name(), c.X.Name()) +} +func (c *MakeSliceConstraint) String() string { + return fmt.Sprintf("%s = make(slice, %s)", c.Y().Name(), c.Size.Name()) +} +func (c *SliceIntervalConstraint) String() string { return fmt.Sprintf("%s = %s", c.Y().Name(), c.I) } + +func (c *SliceAppendConstraint) Eval(g *Graph) Range { + l1 := g.Range(c.A).(SliceInterval).Length + var l2 IntInterval + switch r := g.Range(c.B).(type) { + case SliceInterval: + l2 = r.Length + case StringInterval: + l2 = r.Length + default: + return SliceInterval{} + } + if !l1.IsKnown() || !l2.IsKnown() { + return SliceInterval{} + } + return SliceInterval{ + Length: l1.Add(l2), + } +} +func (c *SliceSliceConstraint) Eval(g *Graph) Range { + lr := NewIntInterval(NewZ(0), NewZ(0)) + if c.Lower != nil { + lr = g.Range(c.Lower).(IntInterval) + } + ur := g.Range(c.X).(SliceInterval).Length + if c.Upper != nil { + ur = g.Range(c.Upper).(IntInterval) + } + if !lr.IsKnown() || !ur.IsKnown() { + return SliceInterval{} + } + + ls := []Z{ + ur.Lower.Sub(lr.Lower), + ur.Upper.Sub(lr.Lower), + ur.Lower.Sub(lr.Upper), + ur.Upper.Sub(lr.Upper), + } + // TODO(dh): if we don't truncate lengths to 0 we might be able to + // easily detect slices with high < low. we'd need to treat -∞ + // specially, though. + for i, l := range ls { + if l.Sign() == -1 { + ls[i] = NewZ(0) + } + } + + return SliceInterval{ + Length: NewIntInterval(MinZ(ls...), MaxZ(ls...)), + } +} +func (c *ArraySliceConstraint) Eval(g *Graph) Range { + lr := NewIntInterval(NewZ(0), NewZ(0)) + if c.Lower != nil { + lr = g.Range(c.Lower).(IntInterval) + } + var l int64 + switch typ := c.X.Type().(type) { + case *types.Array: + l = typ.Len() + case *types.Pointer: + l = typ.Elem().(*types.Array).Len() + } + ur := NewIntInterval(NewZ(l), NewZ(l)) + if c.Upper != nil { + ur = g.Range(c.Upper).(IntInterval) + } + if !lr.IsKnown() || !ur.IsKnown() { + return SliceInterval{} + } + + ls := []Z{ + ur.Lower.Sub(lr.Lower), + ur.Upper.Sub(lr.Lower), + ur.Lower.Sub(lr.Upper), + ur.Upper.Sub(lr.Upper), + } + // TODO(dh): if we don't truncate lengths to 0 we might be able to + // easily detect slices with high < low. we'd need to treat -∞ + // specially, though. + for i, l := range ls { + if l.Sign() == -1 { + ls[i] = NewZ(0) + } + } + + return SliceInterval{ + Length: NewIntInterval(MinZ(ls...), MaxZ(ls...)), + } +} +func (c *SliceIntersectionConstraint) Eval(g *Graph) Range { + xi := g.Range(c.X).(SliceInterval) + if !xi.IsKnown() { + return c.I + } + return SliceInterval{ + Length: xi.Length.Intersection(c.I), + } +} +func (c *SliceLengthConstraint) Eval(g *Graph) Range { + i := g.Range(c.X).(SliceInterval).Length + if !i.IsKnown() { + return NewIntInterval(NewZ(0), PInfinity) + } + return i +} +func (c *MakeSliceConstraint) Eval(g *Graph) Range { + i, ok := g.Range(c.Size).(IntInterval) + if !ok { + return SliceInterval{NewIntInterval(NewZ(0), PInfinity)} + } + if i.Lower.Sign() == -1 { + i.Lower = NewZ(0) + } + return SliceInterval{i} +} +func (c *SliceIntervalConstraint) Eval(*Graph) Range { return SliceInterval{c.I} } diff --git a/vendor/honnef.co/go/tools/staticcheck/vrp/string.go b/vendor/honnef.co/go/tools/staticcheck/vrp/string.go new file mode 100644 index 0000000000..e05877f9f7 --- /dev/null +++ b/vendor/honnef.co/go/tools/staticcheck/vrp/string.go @@ -0,0 +1,258 @@ +package vrp + +import ( + "fmt" + "go/token" + "go/types" + + "honnef.co/go/tools/ssa" +) + +type StringInterval struct { + Length IntInterval +} + +func (s StringInterval) Union(other Range) Range { + i, ok := other.(StringInterval) + if !ok { + i = StringInterval{EmptyIntInterval} + } + if s.Length.Empty() || !s.Length.IsKnown() { + return i + } + if i.Length.Empty() || !i.Length.IsKnown() { + return s + } + return StringInterval{ + Length: s.Length.Union(i.Length).(IntInterval), + } +} + +func (s StringInterval) String() string { + return s.Length.String() +} + +func (s StringInterval) IsKnown() bool { + return s.Length.IsKnown() +} + +type StringSliceConstraint struct { + aConstraint + X ssa.Value + Lower ssa.Value + Upper ssa.Value +} + +type StringIntersectionConstraint struct { + aConstraint + ranges Ranges + A ssa.Value + B ssa.Value + Op token.Token + I IntInterval + resolved bool +} + +type StringConcatConstraint struct { + aConstraint + A ssa.Value + B ssa.Value +} + +type StringLengthConstraint struct { + aConstraint + X ssa.Value +} + +type StringIntervalConstraint struct { + aConstraint + I IntInterval +} + +func NewStringSliceConstraint(x, lower, upper, y ssa.Value) Constraint { + return &StringSliceConstraint{NewConstraint(y), x, lower, upper} +} +func NewStringIntersectionConstraint(a, b ssa.Value, op token.Token, ranges Ranges, y ssa.Value) Constraint { + return &StringIntersectionConstraint{ + aConstraint: NewConstraint(y), + ranges: ranges, + A: a, + B: b, + Op: op, + } +} +func NewStringConcatConstraint(a, b, y ssa.Value) Constraint { + return &StringConcatConstraint{NewConstraint(y), a, b} +} +func NewStringLengthConstraint(x ssa.Value, y ssa.Value) Constraint { + return &StringLengthConstraint{NewConstraint(y), x} +} +func NewStringIntervalConstraint(i IntInterval, y ssa.Value) Constraint { + return &StringIntervalConstraint{NewConstraint(y), i} +} + +func (c *StringSliceConstraint) Operands() []ssa.Value { + vs := []ssa.Value{c.X} + if c.Lower != nil { + vs = append(vs, c.Lower) + } + if c.Upper != nil { + vs = append(vs, c.Upper) + } + return vs +} +func (c *StringIntersectionConstraint) Operands() []ssa.Value { return []ssa.Value{c.A} } +func (c StringConcatConstraint) Operands() []ssa.Value { return []ssa.Value{c.A, c.B} } +func (c *StringLengthConstraint) Operands() []ssa.Value { return []ssa.Value{c.X} } +func (s *StringIntervalConstraint) Operands() []ssa.Value { return nil } + +func (c *StringSliceConstraint) String() string { + var lname, uname string + if c.Lower != nil { + lname = c.Lower.Name() + } + if c.Upper != nil { + uname = c.Upper.Name() + } + return fmt.Sprintf("%s[%s:%s]", c.X.Name(), lname, uname) +} +func (c *StringIntersectionConstraint) String() string { + return fmt.Sprintf("%s = %s %s %s (%t branch)", c.Y().Name(), c.A.Name(), c.Op, c.B.Name(), c.Y().(*ssa.Sigma).Branch) +} +func (c StringConcatConstraint) String() string { + return fmt.Sprintf("%s = %s + %s", c.Y().Name(), c.A.Name(), c.B.Name()) +} +func (c *StringLengthConstraint) String() string { + return fmt.Sprintf("%s = len(%s)", c.Y().Name(), c.X.Name()) +} +func (c *StringIntervalConstraint) String() string { return fmt.Sprintf("%s = %s", c.Y().Name(), c.I) } + +func (c *StringSliceConstraint) Eval(g *Graph) Range { + lr := NewIntInterval(NewZ(0), NewZ(0)) + if c.Lower != nil { + lr = g.Range(c.Lower).(IntInterval) + } + ur := g.Range(c.X).(StringInterval).Length + if c.Upper != nil { + ur = g.Range(c.Upper).(IntInterval) + } + if !lr.IsKnown() || !ur.IsKnown() { + return StringInterval{} + } + + ls := []Z{ + ur.Lower.Sub(lr.Lower), + ur.Upper.Sub(lr.Lower), + ur.Lower.Sub(lr.Upper), + ur.Upper.Sub(lr.Upper), + } + // TODO(dh): if we don't truncate lengths to 0 we might be able to + // easily detect slices with high < low. we'd need to treat -∞ + // specially, though. + for i, l := range ls { + if l.Sign() == -1 { + ls[i] = NewZ(0) + } + } + + return StringInterval{ + Length: NewIntInterval(MinZ(ls...), MaxZ(ls...)), + } +} +func (c *StringIntersectionConstraint) Eval(g *Graph) Range { + var l IntInterval + switch r := g.Range(c.A).(type) { + case StringInterval: + l = r.Length + case IntInterval: + l = r + } + + if !l.IsKnown() { + return StringInterval{c.I} + } + return StringInterval{ + Length: l.Intersection(c.I), + } +} +func (c StringConcatConstraint) Eval(g *Graph) Range { + i1, i2 := g.Range(c.A).(StringInterval), g.Range(c.B).(StringInterval) + if !i1.Length.IsKnown() || !i2.Length.IsKnown() { + return StringInterval{} + } + return StringInterval{ + Length: i1.Length.Add(i2.Length), + } +} +func (c *StringLengthConstraint) Eval(g *Graph) Range { + i := g.Range(c.X).(StringInterval).Length + if !i.IsKnown() { + return NewIntInterval(NewZ(0), PInfinity) + } + return i +} +func (c *StringIntervalConstraint) Eval(*Graph) Range { return StringInterval{c.I} } + +func (c *StringIntersectionConstraint) Futures() []ssa.Value { + return []ssa.Value{c.B} +} + +func (c *StringIntersectionConstraint) Resolve() { + if (c.A.Type().Underlying().(*types.Basic).Info() & types.IsString) != 0 { + // comparing two strings + r, ok := c.ranges[c.B].(StringInterval) + if !ok { + c.I = NewIntInterval(NewZ(0), PInfinity) + return + } + switch c.Op { + case token.EQL: + c.I = r.Length + case token.GTR, token.GEQ: + c.I = NewIntInterval(r.Length.Lower, PInfinity) + case token.LSS, token.LEQ: + c.I = NewIntInterval(NewZ(0), r.Length.Upper) + case token.NEQ: + default: + panic("unsupported op " + c.Op.String()) + } + } else { + r, ok := c.ranges[c.B].(IntInterval) + if !ok { + c.I = NewIntInterval(NewZ(0), PInfinity) + return + } + // comparing two lengths + switch c.Op { + case token.EQL: + c.I = r + case token.GTR: + c.I = NewIntInterval(r.Lower.Add(NewZ(1)), PInfinity) + case token.GEQ: + c.I = NewIntInterval(r.Lower, PInfinity) + case token.LSS: + c.I = NewIntInterval(NInfinity, r.Upper.Sub(NewZ(1))) + case token.LEQ: + c.I = NewIntInterval(NInfinity, r.Upper) + case token.NEQ: + default: + panic("unsupported op " + c.Op.String()) + } + } +} + +func (c *StringIntersectionConstraint) IsKnown() bool { + return c.I.IsKnown() +} + +func (c *StringIntersectionConstraint) MarkUnresolved() { + c.resolved = false +} + +func (c *StringIntersectionConstraint) MarkResolved() { + c.resolved = true +} + +func (c *StringIntersectionConstraint) IsResolved() bool { + return c.resolved +} diff --git a/vendor/honnef.co/go/tools/staticcheck/vrp/vrp.go b/vendor/honnef.co/go/tools/staticcheck/vrp/vrp.go new file mode 100644 index 0000000000..cb17f042ac --- /dev/null +++ b/vendor/honnef.co/go/tools/staticcheck/vrp/vrp.go @@ -0,0 +1,1049 @@ +package vrp + +// TODO(dh) widening and narrowing have a lot of code in common. Make +// it reusable. + +import ( + "fmt" + "go/constant" + "go/token" + "go/types" + "math/big" + "sort" + "strings" + + "honnef.co/go/tools/ssa" +) + +type Future interface { + Constraint + Futures() []ssa.Value + Resolve() + IsKnown() bool + MarkUnresolved() + MarkResolved() + IsResolved() bool +} + +type Range interface { + Union(other Range) Range + IsKnown() bool +} + +type Constraint interface { + Y() ssa.Value + isConstraint() + String() string + Eval(*Graph) Range + Operands() []ssa.Value +} + +type aConstraint struct { + y ssa.Value +} + +func NewConstraint(y ssa.Value) aConstraint { + return aConstraint{y} +} + +func (aConstraint) isConstraint() {} +func (c aConstraint) Y() ssa.Value { return c.y } + +type PhiConstraint struct { + aConstraint + Vars []ssa.Value +} + +func NewPhiConstraint(vars []ssa.Value, y ssa.Value) Constraint { + uniqm := map[ssa.Value]struct{}{} + for _, v := range vars { + uniqm[v] = struct{}{} + } + var uniq []ssa.Value + for v := range uniqm { + uniq = append(uniq, v) + } + return &PhiConstraint{ + aConstraint: NewConstraint(y), + Vars: uniq, + } +} + +func (c *PhiConstraint) Operands() []ssa.Value { + return c.Vars +} + +func (c *PhiConstraint) Eval(g *Graph) Range { + i := Range(nil) + for _, v := range c.Vars { + i = g.Range(v).Union(i) + } + return i +} + +func (c *PhiConstraint) String() string { + names := make([]string, len(c.Vars)) + for i, v := range c.Vars { + names[i] = v.Name() + } + return fmt.Sprintf("%s = φ(%s)", c.Y().Name(), strings.Join(names, ", ")) +} + +func isSupportedType(typ types.Type) bool { + switch typ := typ.Underlying().(type) { + case *types.Basic: + switch typ.Kind() { + case types.String, types.UntypedString: + return true + default: + if (typ.Info() & types.IsInteger) == 0 { + return false + } + } + case *types.Chan: + return true + case *types.Slice: + return true + default: + return false + } + return true +} + +func ConstantToZ(c constant.Value) Z { + s := constant.ToInt(c).ExactString() + n := &big.Int{} + n.SetString(s, 10) + return NewBigZ(n) +} + +func sigmaInteger(g *Graph, ins *ssa.Sigma, cond *ssa.BinOp, ops []*ssa.Value) Constraint { + op := cond.Op + if !ins.Branch { + op = (invertToken(op)) + } + + switch op { + case token.EQL, token.GTR, token.GEQ, token.LSS, token.LEQ: + default: + return nil + } + var a, b ssa.Value + if (*ops[0]) == ins.X { + a = *ops[0] + b = *ops[1] + } else { + a = *ops[1] + b = *ops[0] + op = flipToken(op) + } + return NewIntIntersectionConstraint(a, b, op, g.ranges, ins) +} + +func sigmaString(g *Graph, ins *ssa.Sigma, cond *ssa.BinOp, ops []*ssa.Value) Constraint { + op := cond.Op + if !ins.Branch { + op = (invertToken(op)) + } + + switch op { + case token.EQL, token.GTR, token.GEQ, token.LSS, token.LEQ: + default: + return nil + } + + if ((*ops[0]).Type().Underlying().(*types.Basic).Info() & types.IsString) == 0 { + var a, b ssa.Value + call, ok := (*ops[0]).(*ssa.Call) + if ok && call.Common().Args[0] == ins.X { + a = *ops[0] + b = *ops[1] + } else { + a = *ops[1] + b = *ops[0] + op = flipToken(op) + } + return NewStringIntersectionConstraint(a, b, op, g.ranges, ins) + } + var a, b ssa.Value + if (*ops[0]) == ins.X { + a = *ops[0] + b = *ops[1] + } else { + a = *ops[1] + b = *ops[0] + op = flipToken(op) + } + return NewStringIntersectionConstraint(a, b, op, g.ranges, ins) +} + +func sigmaSlice(g *Graph, ins *ssa.Sigma, cond *ssa.BinOp, ops []*ssa.Value) Constraint { + // TODO(dh) sigmaSlice and sigmaString are a lot alike. Can they + // be merged? + // + // XXX support futures + + op := cond.Op + if !ins.Branch { + op = (invertToken(op)) + } + + k, ok := (*ops[1]).(*ssa.Const) + // XXX investigate in what cases this wouldn't be a Const + // + // XXX what if left and right are swapped? + if !ok { + return nil + } + + call, ok := (*ops[0]).(*ssa.Call) + if !ok { + return nil + } + builtin, ok := call.Common().Value.(*ssa.Builtin) + if !ok { + return nil + } + if builtin.Name() != "len" { + return nil + } + callops := call.Operands(nil) + + v := ConstantToZ(k.Value) + c := NewSliceIntersectionConstraint(*callops[1], IntInterval{}, ins).(*SliceIntersectionConstraint) + switch op { + case token.EQL: + c.I = NewIntInterval(v, v) + case token.GTR, token.GEQ: + off := int64(0) + if cond.Op == token.GTR { + off = 1 + } + c.I = NewIntInterval( + v.Add(NewZ(off)), + PInfinity, + ) + case token.LSS, token.LEQ: + off := int64(0) + if cond.Op == token.LSS { + off = -1 + } + c.I = NewIntInterval( + NInfinity, + v.Add(NewZ(off)), + ) + default: + return nil + } + return c +} + +func BuildGraph(f *ssa.Function) *Graph { + g := &Graph{ + Vertices: map[interface{}]*Vertex{}, + ranges: Ranges{}, + } + + var cs []Constraint + + ops := make([]*ssa.Value, 16) + seen := map[ssa.Value]bool{} + for _, block := range f.Blocks { + for _, ins := range block.Instrs { + ops = ins.Operands(ops[:0]) + for _, op := range ops { + if c, ok := (*op).(*ssa.Const); ok { + if seen[c] { + continue + } + seen[c] = true + if c.Value == nil { + switch c.Type().Underlying().(type) { + case *types.Slice: + cs = append(cs, NewSliceIntervalConstraint(NewIntInterval(NewZ(0), NewZ(0)), c)) + } + continue + } + switch c.Value.Kind() { + case constant.Int: + v := ConstantToZ(c.Value) + cs = append(cs, NewIntIntervalConstraint(NewIntInterval(v, v), c)) + case constant.String: + s := constant.StringVal(c.Value) + n := NewZ(int64(len(s))) + cs = append(cs, NewStringIntervalConstraint(NewIntInterval(n, n), c)) + } + } + } + } + } + for _, block := range f.Blocks { + for _, ins := range block.Instrs { + switch ins := ins.(type) { + case *ssa.Convert: + switch v := ins.Type().Underlying().(type) { + case *types.Basic: + if (v.Info() & types.IsInteger) == 0 { + continue + } + cs = append(cs, NewIntConversionConstraint(ins.X, ins)) + } + case *ssa.Call: + if static := ins.Common().StaticCallee(); static != nil { + if fn, ok := static.Object().(*types.Func); ok { + switch fn.FullName() { + case "bytes.Index", "bytes.IndexAny", "bytes.IndexByte", + "bytes.IndexFunc", "bytes.IndexRune", "bytes.LastIndex", + "bytes.LastIndexAny", "bytes.LastIndexByte", "bytes.LastIndexFunc", + "strings.Index", "strings.IndexAny", "strings.IndexByte", + "strings.IndexFunc", "strings.IndexRune", "strings.LastIndex", + "strings.LastIndexAny", "strings.LastIndexByte", "strings.LastIndexFunc": + // TODO(dh): instead of limiting by +∞, + // limit by the upper bound of the passed + // string + cs = append(cs, NewIntIntervalConstraint(NewIntInterval(NewZ(-1), PInfinity), ins)) + case "bytes.Title", "bytes.ToLower", "bytes.ToTitle", "bytes.ToUpper", + "strings.Title", "strings.ToLower", "strings.ToTitle", "strings.ToUpper": + cs = append(cs, NewCopyConstraint(ins.Common().Args[0], ins)) + case "bytes.ToLowerSpecial", "bytes.ToTitleSpecial", "bytes.ToUpperSpecial", + "strings.ToLowerSpecial", "strings.ToTitleSpecial", "strings.ToUpperSpecial": + cs = append(cs, NewCopyConstraint(ins.Common().Args[1], ins)) + case "bytes.Compare", "strings.Compare": + cs = append(cs, NewIntIntervalConstraint(NewIntInterval(NewZ(-1), NewZ(1)), ins)) + case "bytes.Count", "strings.Count": + // TODO(dh): instead of limiting by +∞, + // limit by the upper bound of the passed + // string. + cs = append(cs, NewIntIntervalConstraint(NewIntInterval(NewZ(0), PInfinity), ins)) + case "bytes.Map", "bytes.TrimFunc", "bytes.TrimLeft", "bytes.TrimLeftFunc", + "bytes.TrimRight", "bytes.TrimRightFunc", "bytes.TrimSpace", + "strings.Map", "strings.TrimFunc", "strings.TrimLeft", "strings.TrimLeftFunc", + "strings.TrimRight", "strings.TrimRightFunc", "strings.TrimSpace": + // TODO(dh): lower = 0, upper = upper of passed string + case "bytes.TrimPrefix", "bytes.TrimSuffix", + "strings.TrimPrefix", "strings.TrimSuffix": + // TODO(dh) range between "unmodified" and len(cutset) removed + case "(*bytes.Buffer).Cap", "(*bytes.Buffer).Len", "(*bytes.Reader).Len", "(*bytes.Reader).Size": + cs = append(cs, NewIntIntervalConstraint(NewIntInterval(NewZ(0), PInfinity), ins)) + } + } + } + builtin, ok := ins.Common().Value.(*ssa.Builtin) + ops := ins.Operands(nil) + if !ok { + continue + } + switch builtin.Name() { + case "len": + switch op1 := (*ops[1]).Type().Underlying().(type) { + case *types.Basic: + if op1.Kind() == types.String || op1.Kind() == types.UntypedString { + cs = append(cs, NewStringLengthConstraint(*ops[1], ins)) + } + case *types.Slice: + cs = append(cs, NewSliceLengthConstraint(*ops[1], ins)) + } + + case "append": + cs = append(cs, NewSliceAppendConstraint(ins.Common().Args[0], ins.Common().Args[1], ins)) + } + case *ssa.BinOp: + ops := ins.Operands(nil) + basic, ok := (*ops[0]).Type().Underlying().(*types.Basic) + if !ok { + continue + } + switch basic.Kind() { + case types.Int, types.Int8, types.Int16, types.Int32, types.Int64, + types.Uint, types.Uint8, types.Uint16, types.Uint32, types.Uint64, types.UntypedInt: + fns := map[token.Token]func(ssa.Value, ssa.Value, ssa.Value) Constraint{ + token.ADD: NewIntAddConstraint, + token.SUB: NewIntSubConstraint, + token.MUL: NewIntMulConstraint, + // XXX support QUO, REM, SHL, SHR + } + fn, ok := fns[ins.Op] + if ok { + cs = append(cs, fn(*ops[0], *ops[1], ins)) + } + case types.String, types.UntypedString: + if ins.Op == token.ADD { + cs = append(cs, NewStringConcatConstraint(*ops[0], *ops[1], ins)) + } + } + case *ssa.Slice: + typ := ins.X.Type().Underlying() + switch typ := typ.(type) { + case *types.Basic: + cs = append(cs, NewStringSliceConstraint(ins.X, ins.Low, ins.High, ins)) + case *types.Slice: + cs = append(cs, NewSliceSliceConstraint(ins.X, ins.Low, ins.High, ins)) + case *types.Array: + cs = append(cs, NewArraySliceConstraint(ins.X, ins.Low, ins.High, ins)) + case *types.Pointer: + if _, ok := typ.Elem().(*types.Array); !ok { + continue + } + cs = append(cs, NewArraySliceConstraint(ins.X, ins.Low, ins.High, ins)) + } + case *ssa.Phi: + if !isSupportedType(ins.Type()) { + continue + } + ops := ins.Operands(nil) + dops := make([]ssa.Value, len(ops)) + for i, op := range ops { + dops[i] = *op + } + cs = append(cs, NewPhiConstraint(dops, ins)) + case *ssa.Sigma: + pred := ins.Block().Preds[0] + instrs := pred.Instrs + cond, ok := instrs[len(instrs)-1].(*ssa.If).Cond.(*ssa.BinOp) + ops := cond.Operands(nil) + if !ok { + continue + } + switch typ := ins.Type().Underlying().(type) { + case *types.Basic: + var c Constraint + switch typ.Kind() { + case types.Int, types.Int8, types.Int16, types.Int32, types.Int64, + types.Uint, types.Uint8, types.Uint16, types.Uint32, types.Uint64, types.UntypedInt: + c = sigmaInteger(g, ins, cond, ops) + case types.String, types.UntypedString: + c = sigmaString(g, ins, cond, ops) + } + if c != nil { + cs = append(cs, c) + } + case *types.Slice: + c := sigmaSlice(g, ins, cond, ops) + if c != nil { + cs = append(cs, c) + } + default: + //log.Printf("unsupported sigma type %T", typ) // XXX + } + case *ssa.MakeChan: + cs = append(cs, NewMakeChannelConstraint(ins.Size, ins)) + case *ssa.MakeSlice: + cs = append(cs, NewMakeSliceConstraint(ins.Len, ins)) + case *ssa.ChangeType: + switch ins.X.Type().Underlying().(type) { + case *types.Chan: + cs = append(cs, NewChannelChangeTypeConstraint(ins.X, ins)) + } + } + } + } + + for _, c := range cs { + if c == nil { + panic("nil constraint") + } + // If V is used in constraint C, then we create an edge V->C + for _, op := range c.Operands() { + g.AddEdge(op, c, false) + } + if c, ok := c.(Future); ok { + for _, op := range c.Futures() { + g.AddEdge(op, c, true) + } + } + // If constraint C defines variable V, then we create an edge + // C->V + g.AddEdge(c, c.Y(), false) + } + + g.FindSCCs() + g.sccEdges = make([][]Edge, len(g.SCCs)) + g.futures = make([][]Future, len(g.SCCs)) + for _, e := range g.Edges { + g.sccEdges[e.From.SCC] = append(g.sccEdges[e.From.SCC], e) + if !e.control { + continue + } + if c, ok := e.To.Value.(Future); ok { + g.futures[e.From.SCC] = append(g.futures[e.From.SCC], c) + } + } + return g +} + +func (g *Graph) Solve() Ranges { + var consts []Z + off := NewZ(1) + for _, n := range g.Vertices { + if c, ok := n.Value.(*ssa.Const); ok { + basic, ok := c.Type().Underlying().(*types.Basic) + if !ok { + continue + } + if (basic.Info() & types.IsInteger) != 0 { + z := ConstantToZ(c.Value) + consts = append(consts, z) + consts = append(consts, z.Add(off)) + consts = append(consts, z.Sub(off)) + } + } + + } + sort.Sort(Zs(consts)) + + for scc, vertices := range g.SCCs { + n := 0 + n = len(vertices) + if n == 1 { + g.resolveFutures(scc) + v := vertices[0] + if v, ok := v.Value.(ssa.Value); ok { + switch typ := v.Type().Underlying().(type) { + case *types.Basic: + switch typ.Kind() { + case types.String, types.UntypedString: + if !g.Range(v).(StringInterval).IsKnown() { + g.SetRange(v, StringInterval{NewIntInterval(NewZ(0), PInfinity)}) + } + default: + if !g.Range(v).(IntInterval).IsKnown() { + g.SetRange(v, InfinityFor(v)) + } + } + case *types.Chan: + if !g.Range(v).(ChannelInterval).IsKnown() { + g.SetRange(v, ChannelInterval{NewIntInterval(NewZ(0), PInfinity)}) + } + case *types.Slice: + if !g.Range(v).(SliceInterval).IsKnown() { + g.SetRange(v, SliceInterval{NewIntInterval(NewZ(0), PInfinity)}) + } + } + } + if c, ok := v.Value.(Constraint); ok { + g.SetRange(c.Y(), c.Eval(g)) + } + } else { + uses := g.uses(scc) + entries := g.entries(scc) + for len(entries) > 0 { + v := entries[len(entries)-1] + entries = entries[:len(entries)-1] + for _, use := range uses[v] { + if g.widen(use, consts) { + entries = append(entries, use.Y()) + } + } + } + + g.resolveFutures(scc) + + // XXX this seems to be necessary, but shouldn't be. + // removing it leads to nil pointer derefs; investigate + // where we're not setting values correctly. + for _, n := range vertices { + if v, ok := n.Value.(ssa.Value); ok { + i, ok := g.Range(v).(IntInterval) + if !ok { + continue + } + if !i.IsKnown() { + g.SetRange(v, InfinityFor(v)) + } + } + } + + actives := g.actives(scc) + for len(actives) > 0 { + v := actives[len(actives)-1] + actives = actives[:len(actives)-1] + for _, use := range uses[v] { + if g.narrow(use) { + actives = append(actives, use.Y()) + } + } + } + } + // propagate scc + for _, edge := range g.sccEdges[scc] { + if edge.control { + continue + } + if edge.From.SCC == edge.To.SCC { + continue + } + if c, ok := edge.To.Value.(Constraint); ok { + g.SetRange(c.Y(), c.Eval(g)) + } + if c, ok := edge.To.Value.(Future); ok { + if !c.IsKnown() { + c.MarkUnresolved() + } + } + } + } + + for v, r := range g.ranges { + i, ok := r.(IntInterval) + if !ok { + continue + } + if (v.Type().Underlying().(*types.Basic).Info() & types.IsUnsigned) == 0 { + if i.Upper != PInfinity { + s := &types.StdSizes{ + // XXX is it okay to assume the largest word size, or do we + // need to be platform specific? + WordSize: 8, + MaxAlign: 1, + } + bits := (s.Sizeof(v.Type()) * 8) - 1 + n := big.NewInt(1) + n = n.Lsh(n, uint(bits)) + upper, lower := &big.Int{}, &big.Int{} + upper.Sub(n, big.NewInt(1)) + lower.Neg(n) + + if i.Upper.Cmp(NewBigZ(upper)) == 1 { + i = NewIntInterval(NInfinity, PInfinity) + } else if i.Lower.Cmp(NewBigZ(lower)) == -1 { + i = NewIntInterval(NInfinity, PInfinity) + } + } + } + + g.ranges[v] = i + } + + return g.ranges +} + +func VertexString(v *Vertex) string { + switch v := v.Value.(type) { + case Constraint: + return v.String() + case ssa.Value: + return v.Name() + case nil: + return "BUG: nil vertex value" + default: + panic(fmt.Sprintf("unexpected type %T", v)) + } +} + +type Vertex struct { + Value interface{} // one of Constraint or ssa.Value + SCC int + index int + lowlink int + stack bool + + Succs []Edge +} + +type Ranges map[ssa.Value]Range + +func (r Ranges) Get(x ssa.Value) Range { + if x == nil { + return nil + } + i, ok := r[x] + if !ok { + switch x := x.Type().Underlying().(type) { + case *types.Basic: + switch x.Kind() { + case types.String, types.UntypedString: + return StringInterval{} + default: + return IntInterval{} + } + case *types.Chan: + return ChannelInterval{} + case *types.Slice: + return SliceInterval{} + } + } + return i +} + +type Graph struct { + Vertices map[interface{}]*Vertex + Edges []Edge + SCCs [][]*Vertex + ranges Ranges + + // map SCCs to futures + futures [][]Future + // map SCCs to edges + sccEdges [][]Edge +} + +func (g Graph) Graphviz() string { + var lines []string + lines = append(lines, "digraph{") + ids := map[interface{}]int{} + i := 1 + for _, v := range g.Vertices { + ids[v] = i + shape := "box" + if _, ok := v.Value.(ssa.Value); ok { + shape = "oval" + } + lines = append(lines, fmt.Sprintf(`n%d [shape="%s", label=%q, colorscheme=spectral11, style="filled", fillcolor="%d"]`, + i, shape, VertexString(v), (v.SCC%11)+1)) + i++ + } + for _, e := range g.Edges { + style := "solid" + if e.control { + style = "dashed" + } + lines = append(lines, fmt.Sprintf(`n%d -> n%d [style="%s"]`, ids[e.From], ids[e.To], style)) + } + lines = append(lines, "}") + return strings.Join(lines, "\n") +} + +func (g *Graph) SetRange(x ssa.Value, r Range) { + g.ranges[x] = r +} + +func (g *Graph) Range(x ssa.Value) Range { + return g.ranges.Get(x) +} + +func (g *Graph) widen(c Constraint, consts []Z) bool { + setRange := func(i Range) { + g.SetRange(c.Y(), i) + } + widenIntInterval := func(oi, ni IntInterval) (IntInterval, bool) { + if !ni.IsKnown() { + return oi, false + } + nlc := NInfinity + nuc := PInfinity + for _, co := range consts { + if co.Cmp(ni.Lower) <= 0 { + nlc = co + break + } + } + for _, co := range consts { + if co.Cmp(ni.Upper) >= 0 { + nuc = co + break + } + } + + if !oi.IsKnown() { + return ni, true + } + if ni.Lower.Cmp(oi.Lower) == -1 && ni.Upper.Cmp(oi.Upper) == 1 { + return NewIntInterval(nlc, nuc), true + } + if ni.Lower.Cmp(oi.Lower) == -1 { + return NewIntInterval(nlc, oi.Upper), true + } + if ni.Upper.Cmp(oi.Upper) == 1 { + return NewIntInterval(oi.Lower, nuc), true + } + return oi, false + } + switch oi := g.Range(c.Y()).(type) { + case IntInterval: + ni := c.Eval(g).(IntInterval) + si, changed := widenIntInterval(oi, ni) + if changed { + setRange(si) + return true + } + return false + case StringInterval: + ni := c.Eval(g).(StringInterval) + si, changed := widenIntInterval(oi.Length, ni.Length) + if changed { + setRange(StringInterval{si}) + return true + } + return false + case SliceInterval: + ni := c.Eval(g).(SliceInterval) + si, changed := widenIntInterval(oi.Length, ni.Length) + if changed { + setRange(SliceInterval{si}) + return true + } + return false + default: + return false + } +} + +func (g *Graph) narrow(c Constraint) bool { + narrowIntInterval := func(oi, ni IntInterval) (IntInterval, bool) { + oLower := oi.Lower + oUpper := oi.Upper + nLower := ni.Lower + nUpper := ni.Upper + + if oLower == NInfinity && nLower != NInfinity { + return NewIntInterval(nLower, oUpper), true + } + if oUpper == PInfinity && nUpper != PInfinity { + return NewIntInterval(oLower, nUpper), true + } + if oLower.Cmp(nLower) == 1 { + return NewIntInterval(nLower, oUpper), true + } + if oUpper.Cmp(nUpper) == -1 { + return NewIntInterval(oLower, nUpper), true + } + return oi, false + } + switch oi := g.Range(c.Y()).(type) { + case IntInterval: + ni := c.Eval(g).(IntInterval) + si, changed := narrowIntInterval(oi, ni) + if changed { + g.SetRange(c.Y(), si) + return true + } + return false + case StringInterval: + ni := c.Eval(g).(StringInterval) + si, changed := narrowIntInterval(oi.Length, ni.Length) + if changed { + g.SetRange(c.Y(), StringInterval{si}) + return true + } + return false + case SliceInterval: + ni := c.Eval(g).(SliceInterval) + si, changed := narrowIntInterval(oi.Length, ni.Length) + if changed { + g.SetRange(c.Y(), SliceInterval{si}) + return true + } + return false + default: + return false + } +} + +func (g *Graph) resolveFutures(scc int) { + for _, c := range g.futures[scc] { + c.Resolve() + } +} + +func (g *Graph) entries(scc int) []ssa.Value { + var entries []ssa.Value + for _, n := range g.Vertices { + if n.SCC != scc { + continue + } + if v, ok := n.Value.(ssa.Value); ok { + // XXX avoid quadratic runtime + // + // XXX I cannot think of any code where the future and its + // variables aren't in the same SCC, in which case this + // code isn't very useful (the variables won't be resolved + // yet). Before we have a cross-SCC example, however, we + // can't really verify that this code is working + // correctly, or indeed doing anything useful. + for _, on := range g.Vertices { + if c, ok := on.Value.(Future); ok { + if c.Y() == v { + if !c.IsResolved() { + g.SetRange(c.Y(), c.Eval(g)) + c.MarkResolved() + } + break + } + } + } + if g.Range(v).IsKnown() { + entries = append(entries, v) + } + } + } + return entries +} + +func (g *Graph) uses(scc int) map[ssa.Value][]Constraint { + m := map[ssa.Value][]Constraint{} + for _, e := range g.sccEdges[scc] { + if e.control { + continue + } + if v, ok := e.From.Value.(ssa.Value); ok { + c := e.To.Value.(Constraint) + sink := c.Y() + if g.Vertices[sink].SCC == scc { + m[v] = append(m[v], c) + } + } + } + return m +} + +func (g *Graph) actives(scc int) []ssa.Value { + var actives []ssa.Value + for _, n := range g.Vertices { + if n.SCC != scc { + continue + } + if v, ok := n.Value.(ssa.Value); ok { + if _, ok := v.(*ssa.Const); !ok { + actives = append(actives, v) + } + } + } + return actives +} + +func (g *Graph) AddEdge(from, to interface{}, ctrl bool) { + vf, ok := g.Vertices[from] + if !ok { + vf = &Vertex{Value: from} + g.Vertices[from] = vf + } + vt, ok := g.Vertices[to] + if !ok { + vt = &Vertex{Value: to} + g.Vertices[to] = vt + } + e := Edge{From: vf, To: vt, control: ctrl} + g.Edges = append(g.Edges, e) + vf.Succs = append(vf.Succs, e) +} + +type Edge struct { + From, To *Vertex + control bool +} + +func (e Edge) String() string { + return fmt.Sprintf("%s -> %s", VertexString(e.From), VertexString(e.To)) +} + +func (g *Graph) FindSCCs() { + // use Tarjan to find the SCCs + + index := 1 + var s []*Vertex + + scc := 0 + var strongconnect func(v *Vertex) + strongconnect = func(v *Vertex) { + // set the depth index for v to the smallest unused index + v.index = index + v.lowlink = index + index++ + s = append(s, v) + v.stack = true + + for _, e := range v.Succs { + w := e.To + if w.index == 0 { + // successor w has not yet been visited; recurse on it + strongconnect(w) + if w.lowlink < v.lowlink { + v.lowlink = w.lowlink + } + } else if w.stack { + // successor w is in stack s and hence in the current scc + if w.index < v.lowlink { + v.lowlink = w.index + } + } + } + + if v.lowlink == v.index { + for { + w := s[len(s)-1] + s = s[:len(s)-1] + w.stack = false + w.SCC = scc + if w == v { + break + } + } + scc++ + } + } + for _, v := range g.Vertices { + if v.index == 0 { + strongconnect(v) + } + } + + g.SCCs = make([][]*Vertex, scc) + for _, n := range g.Vertices { + n.SCC = scc - n.SCC - 1 + g.SCCs[n.SCC] = append(g.SCCs[n.SCC], n) + } +} + +func invertToken(tok token.Token) token.Token { + switch tok { + case token.LSS: + return token.GEQ + case token.GTR: + return token.LEQ + case token.EQL: + return token.NEQ + case token.NEQ: + return token.EQL + case token.GEQ: + return token.LSS + case token.LEQ: + return token.GTR + default: + panic(fmt.Sprintf("unsupported token %s", tok)) + } +} + +func flipToken(tok token.Token) token.Token { + switch tok { + case token.LSS: + return token.GTR + case token.GTR: + return token.LSS + case token.EQL: + return token.EQL + case token.NEQ: + return token.NEQ + case token.GEQ: + return token.LEQ + case token.LEQ: + return token.GEQ + default: + panic(fmt.Sprintf("unsupported token %s", tok)) + } +} + +type CopyConstraint struct { + aConstraint + X ssa.Value +} + +func (c *CopyConstraint) String() string { + return fmt.Sprintf("%s = copy(%s)", c.Y().Name(), c.X.Name()) +} + +func (c *CopyConstraint) Eval(g *Graph) Range { + return g.Range(c.X) +} + +func (c *CopyConstraint) Operands() []ssa.Value { + return []ssa.Value{c.X} +} + +func NewCopyConstraint(x, y ssa.Value) Constraint { + return &CopyConstraint{ + aConstraint: aConstraint{ + y: y, + }, + X: x, + } +} diff --git a/vendor/honnef.co/go/tools/stylecheck/lint.go b/vendor/honnef.co/go/tools/stylecheck/lint.go new file mode 100644 index 0000000000..0659d648c5 --- /dev/null +++ b/vendor/honnef.co/go/tools/stylecheck/lint.go @@ -0,0 +1,599 @@ +package stylecheck // import "honnef.co/go/tools/stylecheck" + +import ( + "fmt" + "go/ast" + "go/constant" + "go/token" + "go/types" + "strconv" + "strings" + "unicode" + "unicode/utf8" + + "honnef.co/go/tools/lint" + . "honnef.co/go/tools/lint/lintdsl" + "honnef.co/go/tools/ssa" + + "golang.org/x/tools/go/types/typeutil" +) + +type Checker struct { + CheckGenerated bool +} + +func NewChecker() *Checker { + return &Checker{} +} + +func (*Checker) Name() string { return "stylecheck" } +func (*Checker) Prefix() string { return "ST" } +func (c *Checker) Init(prog *lint.Program) {} + +func (c *Checker) Checks() []lint.Check { + return []lint.Check{ + {ID: "ST1000", FilterGenerated: false, Fn: c.CheckPackageComment}, + {ID: "ST1001", FilterGenerated: true, Fn: c.CheckDotImports}, + // {ID: "ST1002", FilterGenerated: true, Fn: c.CheckBlankImports}, + {ID: "ST1003", FilterGenerated: true, Fn: c.CheckNames}, + // {ID: "ST1004", FilterGenerated: false, Fn: nil, }, + {ID: "ST1005", FilterGenerated: false, Fn: c.CheckErrorStrings}, + {ID: "ST1006", FilterGenerated: false, Fn: c.CheckReceiverNames}, + // {ID: "ST1007", FilterGenerated: true, Fn: c.CheckIncDec}, + {ID: "ST1008", FilterGenerated: false, Fn: c.CheckErrorReturn}, + // {ID: "ST1009", FilterGenerated: false, Fn: c.CheckUnexportedReturn}, + // {ID: "ST1010", FilterGenerated: false, Fn: c.CheckContextFirstArg}, + {ID: "ST1011", FilterGenerated: false, Fn: c.CheckTimeNames}, + {ID: "ST1012", FilterGenerated: false, Fn: c.CheckErrorVarNames}, + {ID: "ST1013", FilterGenerated: true, Fn: c.CheckHTTPStatusCodes}, + {ID: "ST1015", FilterGenerated: true, Fn: c.CheckDefaultCaseOrder}, + } +} + +func (c *Checker) CheckPackageComment(j *lint.Job) { + // - At least one file in a non-main package should have a package comment + // + // - The comment should be of the form + // "Package x ...". This has a slight potential for false + // positives, as multiple files can have package comments, in + // which case they get appended. But that doesn't happen a lot in + // the real world. + + for _, pkg := range j.Program.InitialPackages { + if pkg.Name == "main" { + continue + } + hasDocs := false + for _, f := range pkg.Syntax { + if IsInTest(j, f) { + continue + } + if f.Doc != nil && len(f.Doc.List) > 0 { + hasDocs = true + prefix := "Package " + f.Name.Name + " " + if !strings.HasPrefix(strings.TrimSpace(f.Doc.Text()), prefix) { + j.Errorf(f.Doc, `package comment should be of the form "%s..."`, prefix) + } + f.Doc.Text() + } + } + + if !hasDocs { + for _, f := range pkg.Syntax { + if IsInTest(j, f) { + continue + } + j.Errorf(f, "at least one file in a package should have a package comment") + } + } + } +} + +func (c *Checker) CheckDotImports(j *lint.Job) { + for _, pkg := range j.Program.InitialPackages { + for _, f := range pkg.Syntax { + imports: + for _, imp := range f.Imports { + path := imp.Path.Value + path = path[1 : len(path)-1] + for _, w := range pkg.Config.DotImportWhitelist { + if w == path { + continue imports + } + } + + if imp.Name != nil && imp.Name.Name == "." && !IsInTest(j, f) { + j.Errorf(imp, "should not use dot imports") + } + } + } + } +} + +func (c *Checker) CheckBlankImports(j *lint.Job) { + fset := j.Program.Fset() + for _, f := range j.Program.Files { + if IsInMain(j, f) || IsInTest(j, f) { + continue + } + + // Collect imports of the form `import _ "foo"`, i.e. with no + // parentheses, as their comment will be associated with the + // (paren-free) GenDecl, not the import spec itself. + // + // We don't directly process the GenDecl so that we can + // correctly handle the following: + // + // import _ "foo" + // import _ "bar" + // + // where only the first import should get flagged. + skip := map[ast.Spec]bool{} + ast.Inspect(f, func(node ast.Node) bool { + switch node := node.(type) { + case *ast.File: + return true + case *ast.GenDecl: + if node.Tok != token.IMPORT { + return false + } + if node.Lparen == token.NoPos && node.Doc != nil { + skip[node.Specs[0]] = true + } + return false + } + return false + }) + for i, imp := range f.Imports { + pos := fset.Position(imp.Pos()) + + if !IsBlank(imp.Name) { + continue + } + // Only flag the first blank import in a group of imports, + // or don't flag any of them, if the first one is + // commented + if i > 0 { + prev := f.Imports[i-1] + prevPos := fset.Position(prev.Pos()) + if pos.Line-1 == prevPos.Line && IsBlank(prev.Name) { + continue + } + } + + if imp.Doc == nil && imp.Comment == nil && !skip[imp] { + j.Errorf(imp, "a blank import should be only in a main or test package, or have a comment justifying it") + } + } + } +} + +func (c *Checker) CheckIncDec(j *lint.Job) { + // TODO(dh): this can be noisy for function bodies that look like this: + // x += 3 + // ... + // x += 2 + // ... + // x += 1 + fn := func(node ast.Node) bool { + assign, ok := node.(*ast.AssignStmt) + if !ok || (assign.Tok != token.ADD_ASSIGN && assign.Tok != token.SUB_ASSIGN) { + return true + } + if (len(assign.Lhs) != 1 || len(assign.Rhs) != 1) || + !IsIntLiteral(assign.Rhs[0], "1") { + return true + } + + suffix := "" + switch assign.Tok { + case token.ADD_ASSIGN: + suffix = "++" + case token.SUB_ASSIGN: + suffix = "--" + } + + j.Errorf(assign, "should replace %s with %s%s", Render(j, assign), Render(j, assign.Lhs[0]), suffix) + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} + +func (c *Checker) CheckErrorReturn(j *lint.Job) { +fnLoop: + for _, fn := range j.Program.InitialFunctions { + sig := fn.Type().(*types.Signature) + rets := sig.Results() + if rets == nil || rets.Len() < 2 { + continue + } + + if rets.At(rets.Len()-1).Type() == types.Universe.Lookup("error").Type() { + // Last return type is error. If the function also returns + // errors in other positions, that's fine. + continue + } + for i := rets.Len() - 2; i >= 0; i-- { + if rets.At(i).Type() == types.Universe.Lookup("error").Type() { + j.Errorf(rets.At(i), "error should be returned as the last argument") + continue fnLoop + } + } + } +} + +// CheckUnexportedReturn checks that exported functions on exported +// types do not return unexported types. +func (c *Checker) CheckUnexportedReturn(j *lint.Job) { + for _, fn := range j.Program.InitialFunctions { + if fn.Synthetic != "" || fn.Parent() != nil { + continue + } + if !ast.IsExported(fn.Name()) || IsInMain(j, fn) || IsInTest(j, fn) { + continue + } + sig := fn.Type().(*types.Signature) + if sig.Recv() != nil && !ast.IsExported(Dereference(sig.Recv().Type()).(*types.Named).Obj().Name()) { + continue + } + res := sig.Results() + for i := 0; i < res.Len(); i++ { + if named, ok := DereferenceR(res.At(i).Type()).(*types.Named); ok && + !ast.IsExported(named.Obj().Name()) && + named != types.Universe.Lookup("error").Type() { + j.Errorf(fn, "should not return unexported type") + } + } + } +} + +func (c *Checker) CheckReceiverNames(j *lint.Job) { + for _, pkg := range j.Program.InitialPackages { + for _, m := range pkg.SSA.Members { + names := map[string]int{} + + var firstFn *types.Func + if T, ok := m.Object().(*types.TypeName); ok { + ms := typeutil.IntuitiveMethodSet(T.Type(), nil) + for _, sel := range ms { + fn := sel.Obj().(*types.Func) + recv := fn.Type().(*types.Signature).Recv() + if Dereference(recv.Type()) != T.Type() { + // skip embedded methods + continue + } + if firstFn == nil { + firstFn = fn + } + if recv.Name() != "" && recv.Name() != "_" { + names[recv.Name()]++ + } + if recv.Name() == "self" || recv.Name() == "this" { + j.Errorf(recv, `receiver name should be a reflection of its identity; don't use generic names such as "this" or "self"`) + } + if recv.Name() == "_" { + j.Errorf(recv, "receiver name should not be an underscore, omit the name if it is unused") + } + } + } + + if len(names) > 1 { + var seen []string + for name, count := range names { + seen = append(seen, fmt.Sprintf("%dx %q", count, name)) + } + + j.Errorf(firstFn, "methods on the same type should have the same receiver name (seen %s)", strings.Join(seen, ", ")) + } + } + } +} + +func (c *Checker) CheckContextFirstArg(j *lint.Job) { + // TODO(dh): this check doesn't apply to test helpers. Example from the stdlib: + // func helperCommandContext(t *testing.T, ctx context.Context, s ...string) (cmd *exec.Cmd) { +fnLoop: + for _, fn := range j.Program.InitialFunctions { + if fn.Synthetic != "" || fn.Parent() != nil { + continue + } + params := fn.Signature.Params() + if params.Len() < 2 { + continue + } + if types.TypeString(params.At(0).Type(), nil) == "context.Context" { + continue + } + for i := 1; i < params.Len(); i++ { + param := params.At(i) + if types.TypeString(param.Type(), nil) == "context.Context" { + j.Errorf(param, "context.Context should be the first argument of a function") + continue fnLoop + } + } + } +} + +func (c *Checker) CheckErrorStrings(j *lint.Job) { + fnNames := map[*ssa.Package]map[string]bool{} + for _, fn := range j.Program.InitialFunctions { + m := fnNames[fn.Package()] + if m == nil { + m = map[string]bool{} + fnNames[fn.Package()] = m + } + m[fn.Name()] = true + } + + for _, fn := range j.Program.InitialFunctions { + if IsInTest(j, fn) { + // We don't care about malformed error messages in tests; + // they're usually for direct human consumption, not part + // of an API + continue + } + for _, block := range fn.Blocks { + instrLoop: + for _, ins := range block.Instrs { + call, ok := ins.(*ssa.Call) + if !ok { + continue + } + if !IsCallTo(call.Common(), "errors.New") && !IsCallTo(call.Common(), "fmt.Errorf") { + continue + } + + k, ok := call.Common().Args[0].(*ssa.Const) + if !ok { + continue + } + + s := constant.StringVal(k.Value) + if len(s) == 0 { + continue + } + switch s[len(s)-1] { + case '.', ':', '!', '\n': + j.Errorf(call, "error strings should not end with punctuation or a newline") + } + idx := strings.IndexByte(s, ' ') + if idx == -1 { + // single word error message, probably not a real + // error but something used in tests or during + // debugging + continue + } + word := s[:idx] + first, n := utf8.DecodeRuneInString(word) + if !unicode.IsUpper(first) { + continue + } + for _, c := range word[n:] { + if unicode.IsUpper(c) { + // Word is probably an initialism or + // multi-word function name + continue instrLoop + } + } + + word = strings.TrimRightFunc(word, func(r rune) bool { return unicode.IsPunct(r) }) + if fnNames[fn.Package()][word] { + // Word is probably the name of a function in this package + continue + } + // First word in error starts with a capital + // letter, and the word doesn't contain any other + // capitals, making it unlikely to be an + // initialism or multi-word function name. + // + // It could still be a proper noun, though. + + j.Errorf(call, "error strings should not be capitalized") + } + } + } +} + +func (c *Checker) CheckTimeNames(j *lint.Job) { + suffixes := []string{ + "Sec", "Secs", "Seconds", + "Msec", "Msecs", + "Milli", "Millis", "Milliseconds", + "Usec", "Usecs", "Microseconds", + "MS", "Ms", + } + fn := func(T types.Type, names []*ast.Ident) { + if !IsType(T, "time.Duration") && !IsType(T, "*time.Duration") { + return + } + for _, name := range names { + for _, suffix := range suffixes { + if strings.HasSuffix(name.Name, suffix) { + j.Errorf(name, "var %s is of type %v; don't use unit-specific suffix %q", name.Name, T, suffix) + break + } + } + } + } + for _, f := range j.Program.Files { + ast.Inspect(f, func(node ast.Node) bool { + switch node := node.(type) { + case *ast.ValueSpec: + T := TypeOf(j, node.Type) + fn(T, node.Names) + case *ast.FieldList: + for _, field := range node.List { + T := TypeOf(j, field.Type) + fn(T, field.Names) + } + } + return true + }) + } +} + +func (c *Checker) CheckErrorVarNames(j *lint.Job) { + for _, f := range j.Program.Files { + for _, decl := range f.Decls { + gen, ok := decl.(*ast.GenDecl) + if !ok || gen.Tok != token.VAR { + continue + } + for _, spec := range gen.Specs { + spec := spec.(*ast.ValueSpec) + if len(spec.Names) != len(spec.Values) { + continue + } + + for i, name := range spec.Names { + val := spec.Values[i] + if !IsCallToAST(j, val, "errors.New") && !IsCallToAST(j, val, "fmt.Errorf") { + continue + } + + prefix := "err" + if name.IsExported() { + prefix = "Err" + } + if !strings.HasPrefix(name.Name, prefix) { + j.Errorf(name, "error var %s should have name of the form %sFoo", name.Name, prefix) + } + } + } + } + } +} + +var httpStatusCodes = map[int]string{ + 100: "StatusContinue", + 101: "StatusSwitchingProtocols", + 102: "StatusProcessing", + 200: "StatusOK", + 201: "StatusCreated", + 202: "StatusAccepted", + 203: "StatusNonAuthoritativeInfo", + 204: "StatusNoContent", + 205: "StatusResetContent", + 206: "StatusPartialContent", + 207: "StatusMultiStatus", + 208: "StatusAlreadyReported", + 226: "StatusIMUsed", + 300: "StatusMultipleChoices", + 301: "StatusMovedPermanently", + 302: "StatusFound", + 303: "StatusSeeOther", + 304: "StatusNotModified", + 305: "StatusUseProxy", + 307: "StatusTemporaryRedirect", + 308: "StatusPermanentRedirect", + 400: "StatusBadRequest", + 401: "StatusUnauthorized", + 402: "StatusPaymentRequired", + 403: "StatusForbidden", + 404: "StatusNotFound", + 405: "StatusMethodNotAllowed", + 406: "StatusNotAcceptable", + 407: "StatusProxyAuthRequired", + 408: "StatusRequestTimeout", + 409: "StatusConflict", + 410: "StatusGone", + 411: "StatusLengthRequired", + 412: "StatusPreconditionFailed", + 413: "StatusRequestEntityTooLarge", + 414: "StatusRequestURITooLong", + 415: "StatusUnsupportedMediaType", + 416: "StatusRequestedRangeNotSatisfiable", + 417: "StatusExpectationFailed", + 418: "StatusTeapot", + 422: "StatusUnprocessableEntity", + 423: "StatusLocked", + 424: "StatusFailedDependency", + 426: "StatusUpgradeRequired", + 428: "StatusPreconditionRequired", + 429: "StatusTooManyRequests", + 431: "StatusRequestHeaderFieldsTooLarge", + 451: "StatusUnavailableForLegalReasons", + 500: "StatusInternalServerError", + 501: "StatusNotImplemented", + 502: "StatusBadGateway", + 503: "StatusServiceUnavailable", + 504: "StatusGatewayTimeout", + 505: "StatusHTTPVersionNotSupported", + 506: "StatusVariantAlsoNegotiates", + 507: "StatusInsufficientStorage", + 508: "StatusLoopDetected", + 510: "StatusNotExtended", + 511: "StatusNetworkAuthenticationRequired", +} + +func (c *Checker) CheckHTTPStatusCodes(j *lint.Job) { + for _, pkg := range j.Program.InitialPackages { + whitelist := map[string]bool{} + for _, code := range pkg.Config.HTTPStatusCodeWhitelist { + whitelist[code] = true + } + fn := func(node ast.Node) bool { + call, ok := node.(*ast.CallExpr) + if !ok { + return true + } + + var arg int + switch CallNameAST(j, call) { + case "net/http.Error": + arg = 2 + case "net/http.Redirect": + arg = 3 + case "net/http.StatusText": + arg = 0 + case "net/http.RedirectHandler": + arg = 1 + default: + return true + } + lit, ok := call.Args[arg].(*ast.BasicLit) + if !ok { + return true + } + if whitelist[lit.Value] { + return true + } + + n, err := strconv.Atoi(lit.Value) + if err != nil { + return true + } + s, ok := httpStatusCodes[n] + if !ok { + return true + } + j.Errorf(lit, "should use constant http.%s instead of numeric literal %d", s, n) + return true + } + for _, f := range pkg.Syntax { + ast.Inspect(f, fn) + } + } +} + +func (c *Checker) CheckDefaultCaseOrder(j *lint.Job) { + fn := func(node ast.Node) bool { + stmt, ok := node.(*ast.SwitchStmt) + if !ok { + return true + } + list := stmt.Body.List + for i, c := range list { + if c.(*ast.CaseClause).List == nil && i != 0 && i != len(list)-1 { + j.Errorf(c, "default case should be first or last in switch statement") + break + } + } + return true + } + for _, f := range j.Program.Files { + ast.Inspect(f, fn) + } +} diff --git a/vendor/honnef.co/go/tools/stylecheck/names.go b/vendor/honnef.co/go/tools/stylecheck/names.go new file mode 100644 index 0000000000..e855590f6b --- /dev/null +++ b/vendor/honnef.co/go/tools/stylecheck/names.go @@ -0,0 +1,263 @@ +// Copyright (c) 2013 The Go Authors. All rights reserved. +// Copyright (c) 2018 Dominik Honnef. All rights reserved. + +package stylecheck + +import ( + "go/ast" + "go/token" + "strings" + "unicode" + + "honnef.co/go/tools/lint" + . "honnef.co/go/tools/lint/lintdsl" +) + +// knownNameExceptions is a set of names that are known to be exempt from naming checks. +// This is usually because they are constrained by having to match names in the +// standard library. +var knownNameExceptions = map[string]bool{ + "LastInsertId": true, // must match database/sql + "kWh": true, +} + +func (c *Checker) CheckNames(j *lint.Job) { + // A large part of this function is copied from + // github.com/golang/lint, Copyright (c) 2013 The Go Authors, + // licensed under the BSD 3-clause license. + + allCaps := func(s string) bool { + for _, r := range s { + if !((r >= 'A' && r <= 'Z') || (r >= '0' && r <= '9') || r == '_') { + return false + } + } + return true + } + + check := func(id *ast.Ident, thing string, initialisms map[string]bool) { + if id.Name == "_" { + return + } + if knownNameExceptions[id.Name] { + return + } + + // Handle two common styles from other languages that don't belong in Go. + if len(id.Name) >= 5 && allCaps(id.Name) && strings.Contains(id.Name, "_") { + j.Errorf(id, "should not use ALL_CAPS in Go names; use CamelCase instead") + return + } + + should := lintName(id.Name, initialisms) + if id.Name == should { + return + } + + if len(id.Name) > 2 && strings.Contains(id.Name[1:len(id.Name)-1], "_") { + j.Errorf(id, "should not use underscores in Go names; %s %s should be %s", thing, id.Name, should) + return + } + j.Errorf(id, "%s %s should be %s", thing, id.Name, should) + } + checkList := func(fl *ast.FieldList, thing string, initialisms map[string]bool) { + if fl == nil { + return + } + for _, f := range fl.List { + for _, id := range f.Names { + check(id, thing, initialisms) + } + } + } + + for _, pkg := range j.Program.InitialPackages { + initialisms := make(map[string]bool, len(pkg.Config.Initialisms)) + for _, word := range pkg.Config.Initialisms { + initialisms[word] = true + } + for _, f := range pkg.Syntax { + // Package names need slightly different handling than other names. + if !strings.HasSuffix(f.Name.Name, "_test") && strings.Contains(f.Name.Name, "_") { + j.Errorf(f, "should not use underscores in package names") + } + if strings.IndexFunc(f.Name.Name, unicode.IsUpper) != -1 { + j.Errorf(f, "should not use MixedCaps in package name; %s should be %s", f.Name.Name, strings.ToLower(f.Name.Name)) + } + + ast.Inspect(f, func(node ast.Node) bool { + switch v := node.(type) { + case *ast.AssignStmt: + if v.Tok != token.DEFINE { + return true + } + for _, exp := range v.Lhs { + if id, ok := exp.(*ast.Ident); ok { + check(id, "var", initialisms) + } + } + case *ast.FuncDecl: + // Functions with no body are defined elsewhere (in + // assembly, or via go:linkname). These are likely to + // be something very low level (such as the runtime), + // where our rules don't apply. + if v.Body == nil { + return true + } + + if IsInTest(j, v) && (strings.HasPrefix(v.Name.Name, "Example") || strings.HasPrefix(v.Name.Name, "Test") || strings.HasPrefix(v.Name.Name, "Benchmark")) { + return true + } + + thing := "func" + if v.Recv != nil { + thing = "method" + } + + if !isTechnicallyExported(v) { + check(v.Name, thing, initialisms) + } + + checkList(v.Type.Params, thing+" parameter", initialisms) + checkList(v.Type.Results, thing+" result", initialisms) + case *ast.GenDecl: + if v.Tok == token.IMPORT { + return true + } + var thing string + switch v.Tok { + case token.CONST: + thing = "const" + case token.TYPE: + thing = "type" + case token.VAR: + thing = "var" + } + for _, spec := range v.Specs { + switch s := spec.(type) { + case *ast.TypeSpec: + check(s.Name, thing, initialisms) + case *ast.ValueSpec: + for _, id := range s.Names { + check(id, thing, initialisms) + } + } + } + case *ast.InterfaceType: + // Do not check interface method names. + // They are often constrainted by the method names of concrete types. + for _, x := range v.Methods.List { + ft, ok := x.Type.(*ast.FuncType) + if !ok { // might be an embedded interface name + continue + } + checkList(ft.Params, "interface method parameter", initialisms) + checkList(ft.Results, "interface method result", initialisms) + } + case *ast.RangeStmt: + if v.Tok == token.ASSIGN { + return true + } + if id, ok := v.Key.(*ast.Ident); ok { + check(id, "range var", initialisms) + } + if id, ok := v.Value.(*ast.Ident); ok { + check(id, "range var", initialisms) + } + case *ast.StructType: + for _, f := range v.Fields.List { + for _, id := range f.Names { + check(id, "struct field", initialisms) + } + } + } + return true + }) + } + } +} + +// lintName returns a different name if it should be different. +func lintName(name string, initialisms map[string]bool) (should string) { + // A large part of this function is copied from + // github.com/golang/lint, Copyright (c) 2013 The Go Authors, + // licensed under the BSD 3-clause license. + + // Fast path for simple cases: "_" and all lowercase. + if name == "_" { + return name + } + if strings.IndexFunc(name, func(r rune) bool { return !unicode.IsLower(r) }) == -1 { + return name + } + + // Split camelCase at any lower->upper transition, and split on underscores. + // Check each word for common initialisms. + runes := []rune(name) + w, i := 0, 0 // index of start of word, scan + for i+1 <= len(runes) { + eow := false // whether we hit the end of a word + if i+1 == len(runes) { + eow = true + } else if runes[i+1] == '_' && i+1 != len(runes)-1 { + // underscore; shift the remainder forward over any run of underscores + eow = true + n := 1 + for i+n+1 < len(runes) && runes[i+n+1] == '_' { + n++ + } + + // Leave at most one underscore if the underscore is between two digits + if i+n+1 < len(runes) && unicode.IsDigit(runes[i]) && unicode.IsDigit(runes[i+n+1]) { + n-- + } + + copy(runes[i+1:], runes[i+n+1:]) + runes = runes[:len(runes)-n] + } else if unicode.IsLower(runes[i]) && !unicode.IsLower(runes[i+1]) { + // lower->non-lower + eow = true + } + i++ + if !eow { + continue + } + + // [w,i) is a word. + word := string(runes[w:i]) + if u := strings.ToUpper(word); initialisms[u] { + // Keep consistent case, which is lowercase only at the start. + if w == 0 && unicode.IsLower(runes[w]) { + u = strings.ToLower(u) + } + // All the common initialisms are ASCII, + // so we can replace the bytes exactly. + // TODO(dh): this won't be true once we allow custom initialisms + copy(runes[w:], []rune(u)) + } else if w > 0 && strings.ToLower(word) == word { + // already all lowercase, and not the first word, so uppercase the first character. + runes[w] = unicode.ToUpper(runes[w]) + } + w = i + } + return string(runes) +} + +func isTechnicallyExported(f *ast.FuncDecl) bool { + if f.Recv != nil || f.Doc == nil { + return false + } + + const export = "//export " + const linkname = "//go:linkname " + for _, c := range f.Doc.List { + if strings.HasPrefix(c.Text, export) && len(c.Text) == len(export)+len(f.Name.Name) && c.Text[len(export):] == f.Name.Name { + return true + } + + if strings.HasPrefix(c.Text, linkname) { + return true + } + } + return false +} diff --git a/vendor/honnef.co/go/tools/unused/unused.go b/vendor/honnef.co/go/tools/unused/unused.go new file mode 100644 index 0000000000..c1088c7ad3 --- /dev/null +++ b/vendor/honnef.co/go/tools/unused/unused.go @@ -0,0 +1,1087 @@ +package unused // import "honnef.co/go/tools/unused" + +import ( + "fmt" + "go/ast" + "go/token" + "go/types" + "io" + "path/filepath" + "strings" + + "honnef.co/go/tools/lint" + . "honnef.co/go/tools/lint/lintdsl" + + "golang.org/x/tools/go/packages" + "golang.org/x/tools/go/types/typeutil" +) + +func NewLintChecker(c *Checker) *LintChecker { + l := &LintChecker{ + c: c, + } + return l +} + +type LintChecker struct { + c *Checker +} + +func (*LintChecker) Name() string { return "unused" } +func (*LintChecker) Prefix() string { return "U" } + +func (l *LintChecker) Init(*lint.Program) {} +func (l *LintChecker) Checks() []lint.Check { + return []lint.Check{ + {ID: "U1000", FilterGenerated: true, Fn: l.Lint}, + } +} + +func typString(obj types.Object) string { + switch obj := obj.(type) { + case *types.Func: + return "func" + case *types.Var: + if obj.IsField() { + return "field" + } + return "var" + case *types.Const: + return "const" + case *types.TypeName: + return "type" + default: + // log.Printf("%T", obj) + return "identifier" + } +} + +func (l *LintChecker) Lint(j *lint.Job) { + unused := l.c.Check(j.Program) + for _, u := range unused { + name := u.Obj.Name() + if sig, ok := u.Obj.Type().(*types.Signature); ok && sig.Recv() != nil { + switch sig.Recv().Type().(type) { + case *types.Named, *types.Pointer: + typ := types.TypeString(sig.Recv().Type(), func(*types.Package) string { return "" }) + if len(typ) > 0 && typ[0] == '*' { + name = fmt.Sprintf("(%s).%s", typ, u.Obj.Name()) + } else if len(typ) > 0 { + name = fmt.Sprintf("%s.%s", typ, u.Obj.Name()) + } + } + } + j.Errorf(u.Obj, "%s %s is unused", typString(u.Obj), name) + } +} + +type graph struct { + roots []*graphNode + nodes map[interface{}]*graphNode +} + +func (g *graph) markUsedBy(obj, usedBy interface{}) { + objNode := g.getNode(obj) + usedByNode := g.getNode(usedBy) + if objNode.obj == usedByNode.obj { + return + } + usedByNode.uses[objNode] = struct{}{} +} + +var labelCounter = 1 + +func (g *graph) getNode(obj interface{}) *graphNode { + for { + if pt, ok := obj.(*types.Pointer); ok { + obj = pt.Elem() + } else { + break + } + } + _, ok := g.nodes[obj] + if !ok { + g.addObj(obj) + } + + return g.nodes[obj] +} + +func (g *graph) addObj(obj interface{}) { + if pt, ok := obj.(*types.Pointer); ok { + obj = pt.Elem() + } + node := &graphNode{obj: obj, uses: make(map[*graphNode]struct{}), n: labelCounter} + g.nodes[obj] = node + labelCounter++ + + if obj, ok := obj.(*types.Struct); ok { + n := obj.NumFields() + for i := 0; i < n; i++ { + field := obj.Field(i) + g.markUsedBy(obj, field) + } + } +} + +type graphNode struct { + obj interface{} + uses map[*graphNode]struct{} + used bool + quiet bool + n int +} + +type CheckMode int + +const ( + CheckConstants CheckMode = 1 << iota + CheckFields + CheckFunctions + CheckTypes + CheckVariables + + CheckAll = CheckConstants | CheckFields | CheckFunctions | CheckTypes | CheckVariables +) + +type Unused struct { + Obj types.Object + Position token.Position +} + +type Checker struct { + Mode CheckMode + WholeProgram bool + ConsiderReflection bool + Debug io.Writer + + graph *graph + + msCache typeutil.MethodSetCache + prog *lint.Program + topmostCache map[*types.Scope]*types.Scope + interfaces []*types.Interface +} + +func NewChecker(mode CheckMode) *Checker { + return &Checker{ + Mode: mode, + graph: &graph{ + nodes: make(map[interface{}]*graphNode), + }, + topmostCache: make(map[*types.Scope]*types.Scope), + } +} + +func (c *Checker) checkConstants() bool { return (c.Mode & CheckConstants) > 0 } +func (c *Checker) checkFields() bool { return (c.Mode & CheckFields) > 0 } +func (c *Checker) checkFunctions() bool { return (c.Mode & CheckFunctions) > 0 } +func (c *Checker) checkTypes() bool { return (c.Mode & CheckTypes) > 0 } +func (c *Checker) checkVariables() bool { return (c.Mode & CheckVariables) > 0 } + +func (c *Checker) markFields(typ types.Type) { + structType, ok := typ.Underlying().(*types.Struct) + if !ok { + return + } + n := structType.NumFields() + for i := 0; i < n; i++ { + field := structType.Field(i) + c.graph.markUsedBy(field, typ) + } +} + +type Error struct { + Errors map[string][]error +} + +func (e Error) Error() string { + return fmt.Sprintf("errors in %d packages", len(e.Errors)) +} + +func (c *Checker) Check(prog *lint.Program) []Unused { + var unused []Unused + c.prog = prog + if c.WholeProgram { + c.findExportedInterfaces() + } + for _, pkg := range prog.InitialPackages { + c.processDefs(pkg) + c.processUses(pkg) + c.processTypes(pkg) + c.processSelections(pkg) + c.processAST(pkg) + } + + for _, node := range c.graph.nodes { + obj, ok := node.obj.(types.Object) + if !ok { + continue + } + typNode, ok := c.graph.nodes[obj.Type()] + if !ok { + continue + } + node.uses[typNode] = struct{}{} + } + + roots := map[*graphNode]struct{}{} + for _, root := range c.graph.roots { + roots[root] = struct{}{} + } + markNodesUsed(roots) + c.markNodesQuiet() + c.deduplicate() + + if c.Debug != nil { + c.printDebugGraph(c.Debug) + } + + for _, node := range c.graph.nodes { + if node.used || node.quiet { + continue + } + obj, ok := node.obj.(types.Object) + if !ok { + continue + } + found := false + if !false { + for _, pkg := range prog.InitialPackages { + if pkg.Types == obj.Pkg() { + found = true + break + } + } + } + if !found { + continue + } + + pos := c.prog.Fset().Position(obj.Pos()) + if pos.Filename == "" || filepath.Base(pos.Filename) == "C" { + continue + } + + unused = append(unused, Unused{Obj: obj, Position: pos}) + } + return unused +} + +// isNoCopyType reports whether a type represents the NoCopy sentinel +// type. The NoCopy type is a named struct with no fields and exactly +// one method `func Lock()` that is empty. +// +// FIXME(dh): currently we're not checking that the function body is +// empty. +func isNoCopyType(typ types.Type) bool { + st, ok := typ.Underlying().(*types.Struct) + if !ok { + return false + } + if st.NumFields() != 0 { + return false + } + + named, ok := typ.(*types.Named) + if !ok { + return false + } + if named.NumMethods() != 1 { + return false + } + meth := named.Method(0) + if meth.Name() != "Lock" { + return false + } + sig := meth.Type().(*types.Signature) + if sig.Params().Len() != 0 || sig.Results().Len() != 0 { + return false + } + return true +} + +func (c *Checker) useNoCopyFields(typ types.Type) { + if st, ok := typ.Underlying().(*types.Struct); ok { + n := st.NumFields() + for i := 0; i < n; i++ { + field := st.Field(i) + if isNoCopyType(field.Type()) { + c.graph.markUsedBy(field, typ) + c.graph.markUsedBy(field.Type().(*types.Named).Method(0), field.Type()) + } + } + } +} + +func (c *Checker) useExportedFields(typ types.Type, by types.Type) bool { + any := false + if st, ok := typ.Underlying().(*types.Struct); ok { + n := st.NumFields() + for i := 0; i < n; i++ { + field := st.Field(i) + if field.Anonymous() { + if c.useExportedFields(field.Type(), typ) { + c.graph.markUsedBy(field, typ) + } + } + if field.Exported() { + c.graph.markUsedBy(field, by) + any = true + } + } + } + return any +} + +func (c *Checker) useExportedMethods(typ types.Type) { + named, ok := typ.(*types.Named) + if !ok { + return + } + ms := typeutil.IntuitiveMethodSet(named, &c.msCache) + for i := 0; i < len(ms); i++ { + meth := ms[i].Obj() + if meth.Exported() { + c.graph.markUsedBy(meth, typ) + } + } + + st, ok := named.Underlying().(*types.Struct) + if !ok { + return + } + n := st.NumFields() + for i := 0; i < n; i++ { + field := st.Field(i) + if !field.Anonymous() { + continue + } + ms := typeutil.IntuitiveMethodSet(field.Type(), &c.msCache) + for j := 0; j < len(ms); j++ { + if ms[j].Obj().Exported() { + c.graph.markUsedBy(field, typ) + break + } + } + } +} + +func (c *Checker) processDefs(pkg *lint.Pkg) { + for _, obj := range pkg.TypesInfo.Defs { + if obj == nil { + continue + } + c.graph.getNode(obj) + + if obj, ok := obj.(*types.TypeName); ok { + c.graph.markUsedBy(obj.Type().Underlying(), obj.Type()) + c.graph.markUsedBy(obj.Type(), obj) // TODO is this needed? + c.graph.markUsedBy(obj, obj.Type()) + + // We mark all exported fields as used. For normal + // operation, we have to. The user may use these fields + // without us knowing. + // + // TODO(dh): In whole-program mode, however, we mark them + // as used because of reflection (such as JSON + // marshaling). Strictly speaking, we would only need to + // mark them used if an instance of the type was + // accessible via an interface value. + if !c.WholeProgram || c.ConsiderReflection { + c.useExportedFields(obj.Type(), obj.Type()) + } + + // TODO(dh): Traditionally we have not marked all exported + // methods as exported, even though they're strictly + // speaking accessible through reflection. We've done that + // because using methods just via reflection is rare, and + // not worth the false negatives. With the new -reflect + // flag, however, we should reconsider that choice. + if !c.WholeProgram { + c.useExportedMethods(obj.Type()) + } + } + + switch obj := obj.(type) { + case *types.Var, *types.Const, *types.Func, *types.TypeName: + if obj.Exported() { + // Exported variables and constants use their types, + // even if there's no expression using them in the + // checked program. + // + // Also operates on funcs and type names, but that's + // irrelevant/redundant. + c.graph.markUsedBy(obj.Type(), obj) + } + if obj.Name() == "_" { + node := c.graph.getNode(obj) + node.quiet = true + scope := c.topmostScope(pkg.Types.Scope().Innermost(obj.Pos()), pkg.Types) + if scope == pkg.Types.Scope() { + c.graph.roots = append(c.graph.roots, node) + } else { + c.graph.markUsedBy(obj, scope) + } + } else { + // Variables declared in functions are used. This is + // done so that arguments and return parameters are + // always marked as used. + if _, ok := obj.(*types.Var); ok { + if obj.Parent() != obj.Pkg().Scope() && obj.Parent() != nil { + c.graph.markUsedBy(obj, c.topmostScope(obj.Parent(), obj.Pkg())) + c.graph.markUsedBy(obj.Type(), obj) + } + } + } + } + + if fn, ok := obj.(*types.Func); ok { + // A function uses its signature + c.graph.markUsedBy(fn, fn.Type()) + + // A function uses its return types + sig := fn.Type().(*types.Signature) + res := sig.Results() + n := res.Len() + for i := 0; i < n; i++ { + c.graph.markUsedBy(res.At(i).Type(), fn) + } + } + + if obj, ok := obj.(interface { + Scope() *types.Scope + Pkg() *types.Package + }); ok { + scope := obj.Scope() + c.graph.markUsedBy(c.topmostScope(scope, obj.Pkg()), obj) + } + + if c.isRoot(obj) { + node := c.graph.getNode(obj) + c.graph.roots = append(c.graph.roots, node) + if obj, ok := obj.(*types.PkgName); ok { + scope := obj.Pkg().Scope() + c.graph.markUsedBy(scope, obj) + } + } + } +} + +func (c *Checker) processUses(pkg *lint.Pkg) { + for ident, usedObj := range pkg.TypesInfo.Uses { + if _, ok := usedObj.(*types.PkgName); ok { + continue + } + pos := ident.Pos() + scope := pkg.Types.Scope().Innermost(pos) + scope = c.topmostScope(scope, pkg.Types) + if scope != pkg.Types.Scope() { + c.graph.markUsedBy(usedObj, scope) + } + + switch usedObj.(type) { + case *types.Var, *types.Const: + c.graph.markUsedBy(usedObj.Type(), usedObj) + } + } +} + +func (c *Checker) findExportedInterfaces() { + c.interfaces = []*types.Interface{types.Universe.Lookup("error").Type().(*types.Named).Underlying().(*types.Interface)} + var pkgs []*packages.Package + if c.WholeProgram { + pkgs = append(pkgs, c.prog.AllPackages...) + } else { + for _, pkg := range c.prog.InitialPackages { + pkgs = append(pkgs, pkg.Package) + } + } + + for _, pkg := range pkgs { + for _, tv := range pkg.TypesInfo.Types { + iface, ok := tv.Type.(*types.Interface) + if !ok { + continue + } + if iface.NumMethods() == 0 { + continue + } + c.interfaces = append(c.interfaces, iface) + } + } +} + +func (c *Checker) processTypes(pkg *lint.Pkg) { + named := map[*types.Named]*types.Pointer{} + var interfaces []*types.Interface + for _, tv := range pkg.TypesInfo.Types { + if typ, ok := tv.Type.(interface { + Elem() types.Type + }); ok { + c.graph.markUsedBy(typ.Elem(), typ) + } + + switch obj := tv.Type.(type) { + case *types.Named: + named[obj] = types.NewPointer(obj) + c.graph.markUsedBy(obj, obj.Underlying()) + c.graph.markUsedBy(obj.Underlying(), obj) + case *types.Interface: + if obj.NumMethods() > 0 { + interfaces = append(interfaces, obj) + } + case *types.Struct: + c.useNoCopyFields(obj) + if pkg.Types.Name() != "main" && !c.WholeProgram { + c.useExportedFields(obj, obj) + } + } + } + + // Pretend that all types are meant to implement as many + // interfaces as possible. + // + // TODO(dh): For normal operations, that's the best we can do, as + // we have no idea what external users will do with our types. In + // whole-program mode, we could be more precise, in two ways: + // 1) Only consider interfaces if a type has been assigned to one + // 2) Use SSA and flow analysis and determine the exact set of + // interfaces that is relevant. + fn := func(iface *types.Interface) { + for i := 0; i < iface.NumEmbeddeds(); i++ { + c.graph.markUsedBy(iface.Embedded(i), iface) + } + for obj, objPtr := range named { + if !types.Implements(obj, iface) && !types.Implements(objPtr, iface) { + continue + } + ifaceMethods := make(map[string]struct{}, iface.NumMethods()) + n := iface.NumMethods() + for i := 0; i < n; i++ { + meth := iface.Method(i) + ifaceMethods[meth.Name()] = struct{}{} + } + for _, obj := range []types.Type{obj, objPtr} { + ms := c.msCache.MethodSet(obj) + n := ms.Len() + for i := 0; i < n; i++ { + sel := ms.At(i) + meth := sel.Obj().(*types.Func) + _, found := ifaceMethods[meth.Name()] + if !found { + continue + } + c.graph.markUsedBy(meth.Type().(*types.Signature).Recv().Type(), obj) // embedded receiver + if len(sel.Index()) > 1 { + f := getField(obj, sel.Index()[0]) + c.graph.markUsedBy(f, obj) // embedded receiver + } + c.graph.markUsedBy(meth, obj) + } + } + } + } + + for _, iface := range interfaces { + fn(iface) + } + for _, iface := range c.interfaces { + fn(iface) + } +} + +func (c *Checker) processSelections(pkg *lint.Pkg) { + fn := func(expr *ast.SelectorExpr, sel *types.Selection, offset int) { + scope := pkg.Types.Scope().Innermost(expr.Pos()) + c.graph.markUsedBy(expr.X, c.topmostScope(scope, pkg.Types)) + c.graph.markUsedBy(sel.Obj(), expr.X) + if len(sel.Index()) > 1 { + typ := sel.Recv() + indices := sel.Index() + for _, idx := range indices[:len(indices)-offset] { + obj := getField(typ, idx) + typ = obj.Type() + c.graph.markUsedBy(obj, expr.X) + } + } + } + + for expr, sel := range pkg.TypesInfo.Selections { + switch sel.Kind() { + case types.FieldVal: + fn(expr, sel, 0) + case types.MethodVal: + fn(expr, sel, 1) + } + } +} + +func dereferenceType(typ types.Type) types.Type { + if typ, ok := typ.(*types.Pointer); ok { + return typ.Elem() + } + return typ +} + +// processConversion marks fields as used if they're part of a type conversion. +func (c *Checker) processConversion(pkg *lint.Pkg, node ast.Node) { + if node, ok := node.(*ast.CallExpr); ok { + callTyp := pkg.TypesInfo.TypeOf(node.Fun) + var typDst *types.Struct + var ok bool + switch typ := callTyp.(type) { + case *types.Named: + typDst, ok = typ.Underlying().(*types.Struct) + case *types.Pointer: + typDst, ok = typ.Elem().Underlying().(*types.Struct) + default: + return + } + if !ok { + return + } + + if typ, ok := pkg.TypesInfo.TypeOf(node.Args[0]).(*types.Basic); ok && typ.Kind() == types.UnsafePointer { + // This is an unsafe conversion. Assume that all the + // fields are relevant (they are, because of memory + // layout) + n := typDst.NumFields() + for i := 0; i < n; i++ { + c.graph.markUsedBy(typDst.Field(i), typDst) + } + return + } + + typSrc, ok := dereferenceType(pkg.TypesInfo.TypeOf(node.Args[0])).Underlying().(*types.Struct) + if !ok { + return + } + + // When we convert from type t1 to t2, were t1 and t2 are + // structs, all fields are relevant, as otherwise the + // conversion would fail. + // + // We mark t2's fields as used by t1's fields, and vice + // versa. That way, if no code actually refers to a field + // in either type, it's still correctly marked as unused. + // If a field is used in either struct, it's implicitly + // relevant in the other one, too. + // + // It works in a similar way for conversions between types + // of two packages, only that the extra information in the + // graph is redundant unless we're in whole program mode. + n := typDst.NumFields() + for i := 0; i < n; i++ { + fDst := typDst.Field(i) + fSrc := typSrc.Field(i) + c.graph.markUsedBy(fDst, fSrc) + c.graph.markUsedBy(fSrc, fDst) + } + } +} + +// processCompositeLiteral marks fields as used if the struct is used +// in a composite literal. +func (c *Checker) processCompositeLiteral(pkg *lint.Pkg, node ast.Node) { + // XXX how does this actually work? wouldn't it match t{}? + if node, ok := node.(*ast.CompositeLit); ok { + typ := pkg.TypesInfo.TypeOf(node) + if _, ok := typ.(*types.Named); ok { + typ = typ.Underlying() + } + if _, ok := typ.(*types.Struct); !ok { + return + } + + if isBasicStruct(node.Elts) { + c.markFields(typ) + } + } +} + +// processCgoExported marks functions as used if they're being +// exported to cgo. +func (c *Checker) processCgoExported(pkg *lint.Pkg, node ast.Node) { + if node, ok := node.(*ast.FuncDecl); ok { + if node.Doc == nil { + return + } + for _, cmt := range node.Doc.List { + if !strings.HasPrefix(cmt.Text, "//go:cgo_export_") { + return + } + obj := pkg.TypesInfo.ObjectOf(node.Name) + c.graph.roots = append(c.graph.roots, c.graph.getNode(obj)) + } + } +} + +func (c *Checker) processVariableDeclaration(pkg *lint.Pkg, node ast.Node) { + if decl, ok := node.(*ast.GenDecl); ok { + for _, spec := range decl.Specs { + spec, ok := spec.(*ast.ValueSpec) + if !ok { + continue + } + for i, name := range spec.Names { + if i >= len(spec.Values) { + break + } + value := spec.Values[i] + fn := func(node ast.Node) bool { + if node3, ok := node.(*ast.Ident); ok { + obj := pkg.TypesInfo.ObjectOf(node3) + if _, ok := obj.(*types.PkgName); ok { + return true + } + c.graph.markUsedBy(obj, pkg.TypesInfo.ObjectOf(name)) + } + return true + } + ast.Inspect(value, fn) + } + } + } +} + +func (c *Checker) processArrayConstants(pkg *lint.Pkg, node ast.Node) { + if decl, ok := node.(*ast.ArrayType); ok { + ident, ok := decl.Len.(*ast.Ident) + if !ok { + return + } + c.graph.markUsedBy(pkg.TypesInfo.ObjectOf(ident), pkg.TypesInfo.TypeOf(decl)) + } +} + +func (c *Checker) processKnownReflectMethodCallers(pkg *lint.Pkg, node ast.Node) { + call, ok := node.(*ast.CallExpr) + if !ok { + return + } + sel, ok := call.Fun.(*ast.SelectorExpr) + if !ok { + return + } + if !IsType(pkg.TypesInfo.TypeOf(sel.X), "*net/rpc.Server") { + x, ok := sel.X.(*ast.Ident) + if !ok { + return + } + pkgname, ok := pkg.TypesInfo.ObjectOf(x).(*types.PkgName) + if !ok { + return + } + if pkgname.Imported().Path() != "net/rpc" { + return + } + } + + var arg ast.Expr + switch sel.Sel.Name { + case "Register": + if len(call.Args) != 1 { + return + } + arg = call.Args[0] + case "RegisterName": + if len(call.Args) != 2 { + return + } + arg = call.Args[1] + } + typ := pkg.TypesInfo.TypeOf(arg) + ms := types.NewMethodSet(typ) + for i := 0; i < ms.Len(); i++ { + c.graph.markUsedBy(ms.At(i).Obj(), typ) + } +} + +func (c *Checker) processAST(pkg *lint.Pkg) { + fn := func(node ast.Node) bool { + c.processConversion(pkg, node) + c.processKnownReflectMethodCallers(pkg, node) + c.processCompositeLiteral(pkg, node) + c.processCgoExported(pkg, node) + c.processVariableDeclaration(pkg, node) + c.processArrayConstants(pkg, node) + return true + } + for _, file := range pkg.Syntax { + ast.Inspect(file, fn) + } +} + +func isBasicStruct(elts []ast.Expr) bool { + for _, elt := range elts { + if _, ok := elt.(*ast.KeyValueExpr); !ok { + return true + } + } + return false +} + +func isPkgScope(obj types.Object) bool { + return obj.Parent() == obj.Pkg().Scope() +} + +func isMain(obj types.Object) bool { + if obj.Pkg().Name() != "main" { + return false + } + if obj.Name() != "main" { + return false + } + if !isPkgScope(obj) { + return false + } + if !isFunction(obj) { + return false + } + if isMethod(obj) { + return false + } + return true +} + +func isFunction(obj types.Object) bool { + _, ok := obj.(*types.Func) + return ok +} + +func isMethod(obj types.Object) bool { + if !isFunction(obj) { + return false + } + return obj.(*types.Func).Type().(*types.Signature).Recv() != nil +} + +func isVariable(obj types.Object) bool { + _, ok := obj.(*types.Var) + return ok +} + +func isConstant(obj types.Object) bool { + _, ok := obj.(*types.Const) + return ok +} + +func isType(obj types.Object) bool { + _, ok := obj.(*types.TypeName) + return ok +} + +func isField(obj types.Object) bool { + if obj, ok := obj.(*types.Var); ok && obj.IsField() { + return true + } + return false +} + +func (c *Checker) checkFlags(v interface{}) bool { + obj, ok := v.(types.Object) + if !ok { + return false + } + if isFunction(obj) && !c.checkFunctions() { + return false + } + if isVariable(obj) && !c.checkVariables() { + return false + } + if isConstant(obj) && !c.checkConstants() { + return false + } + if isType(obj) && !c.checkTypes() { + return false + } + if isField(obj) && !c.checkFields() { + return false + } + return true +} + +func (c *Checker) isRoot(obj types.Object) bool { + // - in local mode, main, init, tests, and non-test, non-main exported are roots + // - in global mode (not yet implemented), main, init and tests are roots + + if _, ok := obj.(*types.PkgName); ok { + return true + } + + if isMain(obj) || (isFunction(obj) && !isMethod(obj) && obj.Name() == "init") { + return true + } + if obj.Exported() { + f := c.prog.Fset().Position(obj.Pos()).Filename + if strings.HasSuffix(f, "_test.go") { + return strings.HasPrefix(obj.Name(), "Test") || + strings.HasPrefix(obj.Name(), "Benchmark") || + strings.HasPrefix(obj.Name(), "Example") + } + + // Package-level are used, except in package main + if isPkgScope(obj) && obj.Pkg().Name() != "main" && !c.WholeProgram { + return true + } + } + return false +} + +func markNodesUsed(nodes map[*graphNode]struct{}) { + for node := range nodes { + wasUsed := node.used + node.used = true + if !wasUsed { + markNodesUsed(node.uses) + } + } +} + +// deduplicate merges objects based on their positions. This is done +// to work around packages existing multiple times in go/packages. +func (c *Checker) deduplicate() { + m := map[token.Position]struct{ used, quiet bool }{} + for _, node := range c.graph.nodes { + obj, ok := node.obj.(types.Object) + if !ok { + continue + } + pos := c.prog.Fset().Position(obj.Pos()) + m[pos] = struct{ used, quiet bool }{ + m[pos].used || node.used, + m[pos].quiet || node.quiet, + } + } + + for _, node := range c.graph.nodes { + obj, ok := node.obj.(types.Object) + if !ok { + continue + } + pos := c.prog.Fset().Position(obj.Pos()) + node.used = m[pos].used + node.quiet = m[pos].quiet + } +} + +func (c *Checker) markNodesQuiet() { + for _, node := range c.graph.nodes { + if node.used { + continue + } + if obj, ok := node.obj.(types.Object); ok && !c.checkFlags(obj) { + node.quiet = true + continue + } + c.markObjQuiet(node.obj) + } +} + +func (c *Checker) markObjQuiet(obj interface{}) { + switch obj := obj.(type) { + case *types.Named: + n := obj.NumMethods() + for i := 0; i < n; i++ { + meth := obj.Method(i) + node := c.graph.getNode(meth) + node.quiet = true + c.markObjQuiet(meth.Scope()) + } + case *types.Struct: + n := obj.NumFields() + for i := 0; i < n; i++ { + field := obj.Field(i) + c.graph.nodes[field].quiet = true + } + case *types.Func: + c.markObjQuiet(obj.Scope()) + case *types.Scope: + if obj == nil { + return + } + if obj.Parent() == types.Universe { + return + } + for _, name := range obj.Names() { + v := obj.Lookup(name) + if n, ok := c.graph.nodes[v]; ok { + n.quiet = true + } + } + n := obj.NumChildren() + for i := 0; i < n; i++ { + c.markObjQuiet(obj.Child(i)) + } + } +} + +func getField(typ types.Type, idx int) *types.Var { + switch obj := typ.(type) { + case *types.Pointer: + return getField(obj.Elem(), idx) + case *types.Named: + switch v := obj.Underlying().(type) { + case *types.Struct: + return v.Field(idx) + case *types.Pointer: + return getField(v.Elem(), idx) + default: + panic(fmt.Sprintf("unexpected type %s", typ)) + } + case *types.Struct: + return obj.Field(idx) + } + return nil +} + +func (c *Checker) topmostScope(scope *types.Scope, pkg *types.Package) (ret *types.Scope) { + if top, ok := c.topmostCache[scope]; ok { + return top + } + defer func() { + c.topmostCache[scope] = ret + }() + if scope == pkg.Scope() { + return scope + } + if scope.Parent().Parent() == pkg.Scope() { + return scope + } + return c.topmostScope(scope.Parent(), pkg) +} + +func (c *Checker) printDebugGraph(w io.Writer) { + fmt.Fprintln(w, "digraph {") + fmt.Fprintln(w, "n0 [label = roots]") + for _, node := range c.graph.nodes { + s := fmt.Sprintf("%s (%T)", node.obj, node.obj) + s = strings.Replace(s, "\n", "", -1) + s = strings.Replace(s, `"`, "", -1) + fmt.Fprintf(w, `n%d [label = %q]`, node.n, s) + color := "black" + switch { + case node.used: + color = "green" + case node.quiet: + color = "orange" + case !c.checkFlags(node.obj): + color = "purple" + default: + color = "red" + } + fmt.Fprintf(w, "[color = %s]", color) + fmt.Fprintln(w) + } + + for _, node1 := range c.graph.nodes { + for node2 := range node1.uses { + fmt.Fprintf(w, "n%d -> n%d\n", node1.n, node2.n) + } + } + for _, root := range c.graph.roots { + fmt.Fprintf(w, "n0 -> n%d\n", root.n) + } + fmt.Fprintln(w, "}") +} diff --git a/vendor/honnef.co/go/tools/version/version.go b/vendor/honnef.co/go/tools/version/version.go new file mode 100644 index 0000000000..232cf7e74f --- /dev/null +++ b/vendor/honnef.co/go/tools/version/version.go @@ -0,0 +1,17 @@ +package version + +import ( + "fmt" + "os" + "path/filepath" +) + +const Version = "devel" + +func Print() { + if Version == "devel" { + fmt.Printf("%s (no version)\n", filepath.Base(os.Args[0])) + } else { + fmt.Printf("%s %s\n", filepath.Base(os.Args[0]), Version) + } +} diff --git a/vendor/modules.txt b/vendor/modules.txt index 54007bc467..94a39d495b 100644 --- a/vendor/modules.txt +++ b/vendor/modules.txt @@ -8,6 +8,8 @@ github.com/Azure/go-autorest/autorest/azure github.com/Azure/go-autorest/autorest/date github.com/Azure/go-autorest/autorest/to github.com/Azure/go-autorest/autorest/validation +# github.com/BurntSushi/toml v0.3.1 +github.com/BurntSushi/toml # github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc github.com/alecthomas/template github.com/alecthomas/template/parse @@ -244,6 +246,18 @@ golang.org/x/text/unicode/norm golang.org/x/text/transform # golang.org/x/time v0.0.0-20170424234030-8be79e1e0910 golang.org/x/time/rate +# golang.org/x/tools v0.0.0-20181023010539-40a48ad93fbe +golang.org/x/tools/go/packages +golang.org/x/tools/go/types/typeutil +golang.org/x/tools/go/ast/astutil +golang.org/x/tools/go/gcexportdata +golang.org/x/tools/go/internal/cgo +golang.org/x/tools/internal/gopathwalk +golang.org/x/tools/internal/semver +golang.org/x/tools/go/loader +golang.org/x/tools/go/internal/gcimporter +golang.org/x/tools/internal/fastwalk +golang.org/x/tools/go/buildutil # google.golang.org/api v0.0.0-20180506000402-20530fd5d65a google.golang.org/api/compute/v1 google.golang.org/api/gensupport @@ -289,6 +303,28 @@ gopkg.in/fsnotify/fsnotify.v1 gopkg.in/inf.v0 # gopkg.in/yaml.v2 v2.2.0 gopkg.in/yaml.v2 +# honnef.co/go/tools v0.0.0-20180910201051-f1b53a58b022 +honnef.co/go/tools/cmd/staticcheck +honnef.co/go/tools/lint +honnef.co/go/tools/lint/lintutil +honnef.co/go/tools/simple +honnef.co/go/tools/staticcheck +honnef.co/go/tools/stylecheck +honnef.co/go/tools/unused +honnef.co/go/tools/config +honnef.co/go/tools/ssa +honnef.co/go/tools/ssa/ssautil +honnef.co/go/tools/lint/lintutil/format +honnef.co/go/tools/version +honnef.co/go/tools/arg +honnef.co/go/tools/internal/sharedcheck +honnef.co/go/tools/lint/lintdsl +honnef.co/go/tools/deprecated +honnef.co/go/tools/functions +honnef.co/go/tools/ssautil +honnef.co/go/tools/staticcheck/vrp +honnef.co/go/tools/callgraph +honnef.co/go/tools/callgraph/static # k8s.io/api v0.0.0-20180628040859-072894a440bd k8s.io/api/core/v1 k8s.io/api/extensions/v1beta1