checkResult(zeroForNull, ITERABLE_1, "1");
    checkResult(zeroForNull, ITERABLE_12, "1-2");
    checkResult(zeroForNull, ITERABLE_123, "1-2-3");
    checkResult(zeroForNull, ITERABLE_NULL, "0");
    checkResult(zeroForNull, ITERABLE_NULL_NULL, "0-0");
    checkResult(zeroForNull, ITERABLE_NULL_1, "0-1");
    checkResult(zeroForNull, ITERABLE_1_NULL, "1-0");
    checkResult(zeroForNull, ITERABLE_1_NULL_2, "1-0-2");

      TestExecutor testExecutor = new TestExecutor(mock);
      List<Future<String>> futures = testExecutor.invokeAll(tasks);
      mock.assertLastMethodCalled("invokeAll");
      checkResults(futures);
    }
    {
      MockExecutor mock = new MockExecutor();
      TimeUnit unit = SECONDS;
      long timeout = 5;
      TestExecutor testExecutor = new TestExecutor(mock);

      TestExecutor testExecutor = new TestExecutor(mock);
      List<Future<String>> futures = testExecutor.invokeAll(tasks);
      mock.assertLastMethodCalled("invokeAll");
      checkResults(futures);
    }
    {
      MockExecutor mock = new MockExecutor();
      TimeUnit unit = SECONDS;
      long timeout = 5;
      TestExecutor testExecutor = new TestExecutor(mock);