@Test(dataProvider = "createTimer")
  public void testHasMessagesToRemove(TimeScheduler timer) {
    try {
      NakReceiverWindow win = new NakReceiverWindow(sender, cmd, 0, timer);
      assert !win.hasMessagesToRemove();
      win.add(2, new Message());
      assert !win.hasMessagesToRemove();
      win.add(1, oob());
      assert win.hasMessagesToRemove();
      win.remove();

      assert win.hasMessagesToRemove();
      win.remove();
      assert !win.hasMessagesToRemove();
    } finally {
      timer.stop();
    }
  }