t.Fatalf("pop %d was not in order", i)
		}
		if peeked != popped {
			t.Fatalf("did not peek at the next item to be popped")
		}
	}
}

func TestDelayQueueOrdering(t *testing.T) {
	dq := NewDelayed(DelayQueueWorkers(2))
	stop := make(chan struct{})
	defer close(stop)
	go dq.Run(stop)

	mu := sync.Mutex{}
	var t0, t1, t2 time.Time

	done := make(chan struct{})
	dq.PushDelayed(func() error {

	//
	// GOMAXPROCS determines how many goroutines can run in parallel,
	// which makes it the best choice as the channel capacity,
	return n
}()

// NewDelayed gives a Delayed queue with maximum concurrency specified by workers.
func NewDelayed(opts ...DelayQueueOption) Delayed {
	q := &delayQueue{
		workers: 1,
		queue:   &pq{},
		execute: make(chan *delayTask, workerChanBuf),