| // Copyright 2014 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 testing_test |
| |
| import ( |
| "fmt" |
| "os" |
| "runtime" |
| "testing" |
| "time" |
| ) |
| |
| func TestMain(m *testing.M) { |
| g0 := runtime.NumGoroutine() |
| |
| code := m.Run() |
| if code != 0 { |
| os.Exit(code) |
| } |
| |
| // Check that there are no goroutines left behind. |
| t0 := time.Now() |
| stacks := make([]byte, 1<<20) |
| for { |
| g1 := runtime.NumGoroutine() |
| if g1 == g0 { |
| return |
| } |
| stacks = stacks[:runtime.Stack(stacks, true)] |
| time.Sleep(50 * time.Millisecond) |
| if time.Since(t0) > 2*time.Second { |
| fmt.Fprintf(os.Stderr, "Unexpected leftover goroutines detected: %v -> %v\n%s\n", g0, g1, stacks) |
| os.Exit(1) |
| } |
| } |
| } |
| |
| func TestContextCancel(t *testing.T) { |
| ctx := t.Context() |
| // Tests we don't leak this goroutine: |
| go func() { |
| <-ctx.Done() |
| }() |
| } |