@Override
  public ParSeqBasedCompletionStage<Void> acceptEither(CompletionStage<? extends T> other, Consumer<? super T> action)
  {
    return produceEitherStage("acceptEither", other, (t) -> {
      action.accept(t);
      return null;
    });
  }
@Test
  public void testAcceptEither_Success_Success() throws Exception
  {
    Consumer<Object> consumer = mock(Consumer.class);
    CompletionStage<String> completionStage = createTestStage(TESTVALUE1);
    CompletionStage<String> completionStage2 = createTestStage(TESTVALUE2);
    finish(completionStage.acceptEither(completionStage2, consumer));
    verify(consumer, times(1)).accept(any(String.class));
  }