close(stop)
	})

	select {
	case <-time.After(200 * time.Millisecond):
		t.Error("close stop, method exit timeout.")
	case <-signal:
		t.Log("queue return.")
	}
}

func TestClosed(t *testing.T) {
	t.Run("immediate close", func(t *testing.T) {
		stop := make(chan struct{})
		q := NewQueue(0)
		go q.Run(stop)
		close(stop)
		if err := WaitForClose(q, 10*time.Second); err != nil {