@Test
public void orderedSlowPathNonEmptyQueue() {

    TestSubscriber<Integer> ts = new TestSubscriber<Integer>(1);
    Disposable d = Disposables.empty();
    QueueDrainSubscriber<Integer, Integer, Integer> qd = createOrdered(ts, d);
    ts.onSubscribe(new BooleanSubscription());
    qd.queue.offer(0);
    qd.requested(2);
    qd.onNext(1);
    ts.assertValuesOnly(0, 1);
}