prometheus/promql/functions_test.go
Matthew 7ee52bfb86
feat: linreg => slope 0 for const values (#9728)
* feat: linreg => slope 0 for const values

Signed-off-by: mtfoley <mtfoley.mae@gmail.com>
2021-11-16 00:03:22 +01:00

87 lines
2.6 KiB
Go

// Copyright 2015 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package promql
import (
"context"
"math"
"testing"
"time"
"github.com/stretchr/testify/require"
"github.com/prometheus/prometheus/model/labels"
"github.com/prometheus/prometheus/model/timestamp"
"github.com/prometheus/prometheus/promql/parser"
"github.com/prometheus/prometheus/util/teststorage"
)
func TestDeriv(t *testing.T) {
// https://github.com/prometheus/prometheus/issues/2674#issuecomment-315439393
// This requires more precision than the usual test system offers,
// so we test it by hand.
storage := teststorage.New(t)
defer storage.Close()
opts := EngineOpts{
Logger: nil,
Reg: nil,
MaxSamples: 10000,
Timeout: 10 * time.Second,
}
engine := NewEngine(opts)
a := storage.Appender(context.Background())
metric := labels.FromStrings("__name__", "foo")
start := 1493712816939
interval := 30 * 1000
// Introduce some timestamp jitter to test 0 slope case.
// https://github.com/prometheus/prometheus/issues/7180
for i := 0; i < 15; i++ {
jitter := 12 * i % 2
a.Append(0, metric, int64(start+interval*i+jitter), 1)
}
require.NoError(t, a.Commit())
query, err := engine.NewInstantQuery(storage, "deriv(foo[30m])", timestamp.Time(1493712846939))
require.NoError(t, err)
result := query.Exec(context.Background())
require.NoError(t, result.Err)
vec, _ := result.Vector()
require.Equal(t, 1, len(vec), "Expected 1 result, got %d", len(vec))
require.Equal(t, 0.0, vec[0].V, "Expected 0.0 as value, got %f", vec[0].V)
}
func TestFunctionList(t *testing.T) {
// Test that Functions and parser.Functions list the same functions.
for i := range FunctionCalls {
_, ok := parser.Functions[i]
require.True(t, ok, "function %s exists in promql package, but not in parser package", i)
}
for i := range parser.Functions {
_, ok := FunctionCalls[i]
require.True(t, ok, "function %s exists in parser package, but not in promql package", i)
}
}
func TestKahanSum(t *testing.T) {
vals := []float64{1.0, math.Pow(10, 100), 1.0, -1 * math.Pow(10, 100)}
expected := 2.0
require.Equal(t, expected, kahanSum(vals))
}