boolean unused = hasNext();
            throw new AssertionError();
          }
        };
    assertThrows(IllegalStateException.class, iter::hasNext);
  }

  // Technically we should test other reentrant scenarios (9 combinations of
  // hasNext/next/peek), but we'll cop out for now, knowing that peek() and
  // next() both start by invoking hasNext() anyway.

    return new CompactStriped<>(stripes, supplier);
  }

  /**
   * Creates a {@code Striped<Lock>} with eagerly initialized, strongly referenced locks. Every lock
   * is reentrant.
   *
   * @param stripes the minimum number of stripes (locks) required
   * @return a new {@code Striped<Lock>}
   */
  public static Striped<Lock> lock(int stripes) {
    return custom(stripes, PaddedLock::new);

            },
            directExecutor()));
    thingToCancel[0] = serializer.submit(Callables.returning(null), directExecutor());
    results.add(thingToCancel[0]);
    // Enqueue more than enough tasks to force reentrancy.
    for (int i = 0; i < 5; i++) {
      results.add(serializer.submit(Callables.returning(null), directExecutor()));
    }

    manualExecutorTask[0].run();

    for (Future<?> result : results) {