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16 commits

Author SHA1 Message Date
beorn7 5b53aa1108 style: Replace else if cascades with switch
Wiser coders than myself have come to the conclusion that a `switch`
statement is almost always superior to a statement that includes any
`else if`.

The exceptions that I have found in our codebase are just these two:

* The `if else` is followed by an additional statement before the next
  condition (separated by a `;`).
* The whole thing is within a `for` loop and `break` statements are
  used. In this case, using `switch` would require tagging the `for`
  loop, which probably tips the balance.

Why are `switch` statements more readable?

For one, fewer curly braces. But more importantly, the conditions all
have the same alignment, so the whole thing follows the natural flow
of going down a list of conditions. With `else if`, in contrast, all
conditions but the first are "hidden" behind `} else if `, harder to
spot and (for no good reason) presented differently from the first
condition.

I'm sure the aforemention wise coders can list even more reasons.

In any case, I like it so much that I have found myself recommending
it in code reviews. I would like to make it a habit in our code base,
without making it a hard requirement that we would test on the CI. But
for that, there has to be a role model, so this commit eliminates all
`if else` occurrences, unless it is autogenerated code or fits one of
the exceptions above.

Signed-off-by: beorn7 <beorn@grafana.com>
2023-04-19 17:22:31 +02:00
beorn7 c3c7d44d84 lint: Adjust to the lint warnings raised by current versions of golint-ci
We haven't updated golint-ci in our CI yet, but this commit prepares
for that.

There are a lot of new warnings, and it is mostly because the "revive"
linter got updated. I agree with most of the new warnings, mostly
around not naming unused function parameters (although it is justified
in some cases for documentation purposes – while things like mocks are
a good example where not naming the parameter is clearer).

I'm pretty upset about the "empty block" warning to include `for`
loops. It's such a common pattern to do something in the head of the
`for` loop and then have an empty block. There is still an open issue
about this: https://github.com/mgechev/revive/issues/810 I have
disabled "revive" altogether in files where empty blocks are used
excessively, and I have made the effort to add individual
`// nolint:revive` where empty blocks are used just once or twice.
It's borderline noisy, though, but let's go with it for now.

I should mention that none of the "empty block" warnings for `for`
loop bodies were legitimate.

Signed-off-by: beorn7 <beorn@grafana.com>
2023-04-19 17:10:10 +02:00
Harkishen Singh 44fcf876ca
Adds support for prettifying PromQL expression (#10544)
* Implement Pretty() function for AST nodes.

Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>

This commit adds .Pretty() for all nodes of PromQL AST.
Each .Pretty() prettifies the node it belongs to, and under
no circustance, the parent or child node is touch/prettified.

Read more in the "Approach" part in `prettier.go`

* Refactor functions between printer.go & prettier.go

Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>

This commit removes redundancy between printer.go and prettier.go
by taking out the common code into separate private functions.

* Add more unit tests for Prettier.

Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>

* Add support for spliting function calls with 1 arg & unary expressions.

Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>

This commit does 2 things:
1. It adds support to split function calls that have 1 arg and exceeds the max_characters_per_line
to multiple lines.
2. Splits Unary expressions that exceed the max_characters_per_line. This is done by formatting the child node
and then removing the prefix indent, which is already applied before the unary operator.
2022-07-07 18:13:36 +05:30
Levi Harrison 8547a2bd86 Add atan2 binary operator
Signed-off-by: Levi Harrison <git@leviharrison.dev>
2021-09-23 10:30:46 -04:00
Danny Kopping 42a0e0acad
Prevent lexer from seeking to next rune after lexing escape sequence. (#8517)
* Prevent lexer from seeking to next rune after lexing escape sequence.

Signed-off-by: Danny Kopping <danny.kopping@grafana.com>
2021-02-19 07:38:05 +01:00
Ganesh Vernekar 86c71856e8
Add start() and end() pre-processors for @ modifier (#8425)
* Add start() and end() pre-processors for @ modifier

Signed-off-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>

* Fix reviews

Signed-off-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>

* Fix review comments

Signed-off-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>

* Fix review comments

Signed-off-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>
2021-02-09 21:33:16 +05:30
Ganesh Vernekar 9199fcb8d1
'@ <timestamp>' modifier (#8121)
This commit adds `@ <timestamp>` modifier as per this design doc: https://docs.google.com/document/d/1uSbD3T2beM-iX4-Hp7V074bzBRiRNlqUdcWP6JTDQSs/edit.

An example query:

```
rate(process_cpu_seconds_total[1m]) 
  and
topk(7, rate(process_cpu_seconds_total[1h] @ 1234))
```

which ranks based on last 1h rate and w.r.t. unix timestamp 1234 but actually plots the 1m rate.

Signed-off-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>
2021-01-20 16:27:39 +05:30
Harkishen Singh fc8e769d71
Use ASSIGN when using = inside braces (#7911)
* Fix EQL when using = inside braces.

Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>

* EQL => EQLC and ASSIGN => EQL

Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>

* Aligned yacc code.

Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>
2020-09-09 15:40:02 +05:30
Julien Pivotto d867491364
Human-friendly durations in PromQL (#7713)
* Add support for user-friendly durations

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-08-04 21:12:41 +02:00
Julien Pivotto 72425d4e3d
Add group() aggregator (#7480)
* Add group() aggregator

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-06-30 16:51:18 +02:00
Guangwen Feng 9ab072b470
Fix golint issue caused by typo (#7475)
Signed-off-by: Guangwen Feng <fenggw-fnst@cn.fujitsu.com>
2020-06-28 11:03:09 +01:00
Ben Kochie 269e7c8091
Fix golint issues.
Signed-off-by: Ben Kochie <superq@gmail.com>
2020-03-23 20:38:43 +01:00
johncming bdc45c2b9e
remove unused code. (#7019)
Signed-off-by: johncming <johncming@yahoo.com>
2020-03-21 07:15:51 +00:00
Tobias Guggenmos 1360f9ff12 Fix all build errors in promql package
Signed-off-by: Tobias Guggenmos <tguggenm@redhat.com>
2020-02-17 16:09:23 +01:00
Tobias Guggenmos 65f5b9827d Rename package
Signed-off-by: Tobias Guggenmos <tguggenm@redhat.com>
2020-02-17 16:05:21 +01:00
Tobias Guggenmos e7c2716f55 Move files
Signed-off-by: Tobias Guggenmos <tguggenm@redhat.com>
2020-02-17 16:05:21 +01:00
Renamed from promql/lex.go (Browse further)