blob: 64bc6c5bbff79cb65931c3a09b8e858d7727f4df [file] [log] [blame]
// 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 stacktest
import (
"testing"
"time"
"golang.org/x/exp/internal/stack"
)
//this is only needed to support pre 1.14 when testing.TB did not have Cleanup
type withCleanup interface {
Cleanup(func())
}
// the maximum amount of time to wait for goroutines to clean themselves up.
const maxWait = time.Second
// NoLeak checks that a test (or benchmark) does not leak any goroutines.
func NoLeak(t testing.TB) {
c, ok := t.(withCleanup)
if !ok {
return
}
before := stack.Capture()
c.Cleanup(func() {
var delta stack.Delta
start := time.Now()
delay := time.Millisecond
for {
after := stack.Capture()
delta = stack.Diff(before, after)
if len(delta.After) == 0 {
// no leaks
return
}
if time.Since(start) > maxWait {
break
}
time.Sleep(delay)
delay *= 2
}
// it's been long enough, and leaks are still present
summary := stack.Summarize(delta.After)
t.Errorf("goroutine leak detected:\n%+v", summary)
})
}