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

  // Technically we should test other reentrant scenarios (4 combinations of
  // hasNext/next), but we'll cop out for now, knowing that
  // next() both start by invoking hasNext() anyway.

  /** Throws an undeclared checked exception. */

            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.

  /** Throws an undeclared checked exception. */

            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.

  /** Throws an undeclared checked exception. */

  }

  public void testReentrancy_noDeadlock() {
    lockA.lock();
    lockB.lock();
    lockA.lock(); // Should not assert on lockB -> reentrant(lockA)
  }

  public void testExplicitOrdering_noViolations() {
    lock1.lock();
    lock3.lock();
    lock3.unlock();
    lock2.lock();
    lock3.lock();
  }

  }

  public void testReentrancy_noDeadlock() {
    lockA.lock();
    lockB.lock();
    lockA.lock(); // Should not assert on lockB -> reentrant(lockA)
  }

  public void testExplicitOrdering_noViolations() {
    lock1.lock();
    lock3.lock();
    lock3.unlock();
    lock2.lock();
    lock3.lock();
  }

       * class with a manual reference back to the "containing" class.)
       *
       * This has the nice-ish side effect of limiting reentrancy: run() calls
       * timeoutFuture.setException() calls run(). That reentrancy would already be harmless, since
       * timeoutFuture can be set (and delegate cancelled) only once. (And "set only once" is

            },
            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) {

            },
            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) {