@Test
public void postCompleteEmpty() {

    TestSubscriber<Integer> ts = new TestSubscriber<Integer>();
    ArrayDeque<Integer> queue = new ArrayDeque<Integer>();
    AtomicLong state = new AtomicLong();
    BooleanSupplier isCancelled = new BooleanSupplier() {
        @Override
        public boolean getAsBoolean() throws Exception {
            return false;
        }
    };
    ts.onSubscribe(new BooleanSubscription());
    QueueDrainHelper.postComplete(ts, queue, state, isCancelled);
    ts.assertResult();
}