t.Errorf("unexpected bucket size: %#v", watchers.watchersBuckets)
	}
	watchers0 := watchers.popExpiredWatchersThreadUnsafe()
	if len(watchers0) != 0 {
		t.Errorf("unexpected bucket size: %#v", watchers0)
	}

	clock.Step(10 * time.Second)
	watchers1 := watchers.popExpiredWatchersThreadUnsafe()
	if len(watchers1) != 1 || len(watchers1[0]) != 1 {
		t.Errorf("unexpected bucket size: %v", watchers1)
	}