package generic_test
// This is package generic_test in order to get around an import cycle: this
// package imports teststat to do its testing, but package teststat imports
// generic to use its Histogram in the Quantiles helper function.
import (
"math"
"math/rand"
"sync"
"testing"
"github.com/go-kit/kit/metrics/generic"
"github.com/go-kit/kit/metrics/teststat"
)
func TestCounter(t *testing.T) {
name := "my_counter"
counter := generic.NewCounter(name).With("label", "counter").(*generic.Counter)
if want, have := name, counter.Name; want != have {
t.Errorf("Name: want %q, have %q", want, have)
}
value := func() float64 { return counter.Value() }
if err := teststat.TestCounter(counter, value); err != nil {
t.Fatal(err)
}
}
func TestValueReset(t *testing.T) {
counter := generic.NewCounter("test_value_reset")
counter.Add(123)
counter.Add(456)
counter.Add(789)
if want, have := float64(123+456+789), counter.ValueReset(); want != have {
t.Errorf("want %f, have %f", want, have)
}
if want, have := float64(0), counter.Value(); want != have {
t.Errorf("want %f, have %f", want, have)
}
}
func TestGauge(t *testing.T) {
name := "my_gauge"
gauge := generic.NewGauge(name).With("label", "gauge").(*generic.Gauge)
if want, have := name, gauge.Name; want != have {
t.Errorf("Name: want %q, have %q", want, have)
}
value := func() float64 { return gauge.Value() }
if err := teststat.TestGauge(gauge, value); err != nil {
t.Fatal(err)
}
}
func TestHistogram(t *testing.T) {
name := "my_histogram"
histogram := generic.NewHistogram(name, 50).With("label", "histogram").(*generic.Histogram)
if want, have := name, histogram.Name; want != have {
t.Errorf("Name: want %q, have %q", want, have)
}
quantiles := func() (float64, float64, float64, float64) {
return histogram.Quantile(0.50), histogram.Quantile(0.90), histogram.Quantile(0.95), histogram.Quantile(0.99)
}
if err := teststat.TestHistogram(histogram, quantiles, 0.01); err != nil {
t.Fatal(err)
}
}
func TestIssue424(t *testing.T) {
var (
histogram = generic.NewHistogram("dont_panic", 50)
concurrency = 100
operations = 1000
wg sync.WaitGroup
)
wg.Add(concurrency)
for i := 0; i < concurrency; i++ {
go func() {
defer wg.Done()
for j := 0; j < operations; j++ {
histogram.Observe(float64(j))
histogram.Observe(histogram.Quantile(0.5))
}
}()
}
wg.Wait()
}
func TestSimpleHistogram(t *testing.T) {
histogram := generic.NewSimpleHistogram().With("label", "simple_histogram").(*generic.SimpleHistogram)
var (
sum int
count = 1234 // not too big
)
for i := 0; i < count; i++ {
value := rand.Intn(1000)
sum += value
histogram.Observe(float64(value))
}
var (
want = float64(sum) / float64(count)
have = histogram.ApproximateMovingAverage()
tolerance = 0.001 // real real slim
)
if math.Abs(want-have)/want > tolerance {
t.Errorf("want %f, have %f", want, have)
}
}