@Override
  public void fulfill(T value) {
    super.fulfill(value);
    postFulfillment();
  }
@Test
  void fetchingAnAlreadyFulfilledPromiseReturnsTheFulfilledValueImmediately()
      throws ExecutionException {
    var promise = new Promise<Integer>();
    promise.fulfill(NumberCrunchingTask.CRUNCHED_NUMBER);

    Integer result = promise.get(1000, TimeUnit.SECONDS);
    assertEquals(NumberCrunchingTask.CRUNCHED_NUMBER, result);
  }