Golang超时测试：验证函数执行时间是否达标

func TestLongRunningFunction_WithTimeout(t *testing.T) {
    ctx, cancel := context.WithTimeout(context.Background(), 150*time.Millisecond)
    defer cancel()
done := make(chan error, 1)
go func() {
    done <- longRunningFunction(ctx) // 函数需支持 context 取消
}()

select {
case err := <-done:
    if err != nil {
        t.Fatalf("function failed: %v", err)
    }
case <-ctx.Done():
    t.Fatal("function timed out")
}
}

func TestCompute_WithFixedTimeout(t *testing.T) {
    resultCh := make(chan int, 1)
    go func() {
        resultCh <- computeHeavyTask() // 不支持 context 的纯函数
    }()
select {
case result := <-resultCh:
    if result != expected {
        t.Errorf("got %d, want %d", result, expected)
    }
case <-time.After(200 * time.Millisecond):
    t.Fatal("computeHeavyTask took too long")
}
}

func MustCompleteWithin(t *testing.T, d time.Duration, f func()) {
    done := make(chan struct{})
    go func() {
        f()
        close(done)
    }()
    select {
    case <-done:
        return
    case <-time.After(d):
        t.Fatalf("function did not complete within %v", d)
    }
}
// 使用
func TestExample(t testing.T) {
MustCompleteWithin(t, 100time.Millisecond, func() {
result = someFunc()
})
if result != expected {
t.Error("wrong result")
}
}