@Test
public void Should_executeReceiverImmediately_When_ActorIsNotBusy()
        throws Exception {

    receiverFlag.set(false);
    doAnswer(invocationOnMock -> {
        assertTrue(receiverFlag.get());
        return null;
    }).when(childReceiverMock).receive(any());
    when(receiverQueueMock.isEmpty()).thenReturn(true);
    ActorReceiver actorReceiver = new ActorReceiver(childReceiverMock);
    actorReceiver.receive(processorMock);
    verify(childReceiverMock).receive(same(processorMock));
}