.config/coc/extensions/coc-go-data/tools/pkg/mod/golang.org/x/tools@v0.0.0-20201105173854-bc9fc8d8c4bc/internal/stack/stacktest/stacktest.go

   1 // Copyright 2018 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package stacktest
   6
   7 import (
   8         "testing"
   9         "time"
  10
  11         "golang.org/x/tools/internal/stack"
  12 )
  13
  14 //this is only needed to support pre 1.14 when testing.TB did not have Cleanup
  15 type withCleanup interface {
  16         Cleanup(func())
  17 }
  18
  19 // the maximum amount of time to wait for goroutines to clean themselves up.
  20 const maxWait = time.Second
  21
  22 // NoLeak checks that a test (or benchmark) does not leak any goroutines.
  23 func NoLeak(t testing.TB) {
  24         c, ok := t.(withCleanup)
  25         if !ok {
  26                 return
  27         }
  28         before := stack.Capture()
  29         c.Cleanup(func() {
  30                 var delta stack.Delta
  31                 start := time.Now()
  32                 delay := time.Millisecond
  33                 for {
  34                         after := stack.Capture()
  35                         delta = stack.Diff(before, after)
  36                         if len(delta.After) == 0 {
  37                                 // no leaks
  38                                 return
  39                         }
  40                         if time.Since(start) > maxWait {
  41                                 break
  42                         }
  43                         time.Sleep(delay)
  44                         delay *= 2
  45                 }
  46                 // it's been long enough, and leaks are still present
  47                 summary := stack.Summarize(delta.After)
  48                 t.Errorf("goroutine leak detected:\n%+v", summary)
  49         })
  50 }