public void testPoll_empty() {
    assertNull("emptyQueue.poll() should return null", getQueue().poll());
    expectUnchanged();
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  @CollectionSize.Require(ONE)
  public void testPoll_size1() {
    assertEquals("size1Queue.poll() should return first element", e0(), getQueue().poll());
    expectMissing(e0());
  }

    //                                                                         Poll Loop
    //                                                                         ===========

    /**
     * Periodic poll that sends a heartbeat, processes new events, and cleans up expired documents.
     */
    protected void poll() {
        try {
            sendHeartbeat();
        } catch (final Exception e) {

  @Override
  public boolean offer(@ParametricNullness E o) {
    return delegate().offer(o);
  }

  @CanIgnoreReturnValue // TODO(cpovirk): Consider removing this?
  @Override
  public @Nullable E poll() {
    return delegate().poll();
  }

  @CanIgnoreReturnValue
  @Override
  @ParametricNullness
  public E remove() {
    return delegate().remove();
  }

  @Override
  public @Nullable E peek() {

   * like [poll]. It is only usable within task faker tasks.
   */
  private inner class TaskFakerBlockingQueue<T>(
    val delegate: BlockingQueue<T>,
  ) : AbstractQueue<T>(),
    BlockingQueue<T> {
    override val size: Int = delegate.size

    private var editCount = 0

    override fun poll(): T = delegate.poll()

    override fun poll(
      timeout: Long,

  @Override
  public boolean offer(@ParametricNullness E o) {
    return delegate().offer(o);
  }

  @CanIgnoreReturnValue // TODO(cpovirk): Consider removing this?
  @Override
  public @Nullable E poll() {
    return delegate().poll();
  }

  @CanIgnoreReturnValue
  @Override
  @ParametricNullness
  public E remove() {
    return delegate().remove();
  }

  @Override
  public @Nullable E peek() {

    return delegate().offer(e, timeout, unit);
  }

  @CanIgnoreReturnValue // TODO(kak): consider removing this
  @Override
  public @Nullable E poll(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().poll(timeout, unit);
  }

  @Override
  public void put(E e) throws InterruptedException {
    delegate().put(e);
  }

  @Override
  public int remainingCapacity() {

    @Override
    public boolean offer(E o) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.offer(o);
    }

    @Override
    public @Nullable E poll() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.poll();
    }

    @Override
    public E remove() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.remove();
    }

    @Override

  }

  @Override
  public E take() throws InterruptedException {
    return delegate().take();
  }

  @Override
  public @Nullable E poll(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().poll(timeout, unit);
  }

  @Override
  public int drainTo(Collection<? super E> c) {
    return delegate().drainTo(c);
  }

  @Override

    while (added < numElements) {
      // we could rely solely on #poll, but #drainTo might be more efficient when there are multiple
      // elements already available (e.g. LinkedBlockingQueue#drainTo locks only once)
      added += q.drainTo(buffer, numElements - added);
      if (added < numElements) { // not enough elements immediately available; will have to poll
        E e = q.poll(deadline - System.nanoTime(), NANOSECONDS);
        if (e == null) {

  }

  @Override
  public E take() throws InterruptedException {
    return delegate().take();
  }

  @Override
  public @Nullable E poll(long timeout, TimeUnit unit) throws InterruptedException {
    return delegate().poll(timeout, unit);
  }

  @Override
  public int drainTo(Collection<? super E> c) {
    return delegate().drainTo(c);
  }

  @Override