public void testSingleTearDown() throws Exception {
    final TearDownStack stack = buildTearDownStack();

    final SimpleTearDown tearDown = new SimpleTearDown();
    stack.addTearDown(tearDown);

    assertEquals(false, tearDown.ran);

    stack.runTearDown();

    assertEquals("tearDown should have run", true, tearDown.ran);
  }

    @Override
    public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks)
        throws InterruptedException {
      lastMethodCalled = "invokeAll";
      assertTaskWrapped(tasks);
      return inline.invokeAll(tasks);
    }

    @Override
    public <T> List<Future<T>> invokeAll(
        Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit)
        throws InterruptedException {

    Preconditions.checkNotNull(unit, "unit must not be null!");
    return delegate.invokeAll(tasks, timeout, unit);
  }

  @Override
  public <T> T invokeAny(Collection<? extends Callable<T>> tasks)
      throws InterruptedException, ExecutionException {
    Preconditions.checkNotNull(tasks, "tasks must not be null!");
    return delegate.invokeAny(tasks);
  }

  @Override

    Preconditions.checkNotNull(unit, "unit must not be null!");
    return delegate.invokeAll(tasks, timeout, unit);
  }

  @Override
  public <T> T invokeAny(Collection<? extends Callable<T>> tasks)
      throws InterruptedException, ExecutionException {
    Preconditions.checkNotNull(tasks, "tasks must not be null!");
    return delegate.invokeAny(tasks);
  }

  @Override

        }
        return pop(stack);
      }

      <E extends @Nullable Object> void push(List<E> stack, E value) {
        stack.add(value);
      }

      <E extends @Nullable Object> E pop(List<E> stack) {
        return stack.remove(stack.size() - 1);
      }
    };

    abstract <T extends @Nullable Object, A extends @Nullable Object, R extends @Nullable Object>

    }

    return builder.buildOrThrow();
  }

  /**
   * Parses a trie node and returns the number of characters consumed.
   *
   * @param stack The prefixes that precede the characters represented by this node. Each entry of
   *     the stack is in reverse order.
   * @param encoded The serialized trie.
   * @param start An index in the encoded serialized trie to begin reading characters from.

  final LinkedList<TearDown> stack = new LinkedList<>();

  private final boolean suppressThrows;

  public TearDownStack() {
    this.suppressThrows = false;
  }

  public TearDownStack(boolean suppressThrows) {
    this.suppressThrows = suppressThrows;
  }

  @Override
  public final void addTearDown(TearDown tearDown) {
    synchronized (lock) {
      stack.addFirst(checkNotNull(tearDown));
    }
  }

  final LinkedList<TearDown> stack = new LinkedList<>();

  private final boolean suppressThrows;

  public TearDownStack() {
    this.suppressThrows = false;
  }

  public TearDownStack(boolean suppressThrows) {
    this.suppressThrows = suppressThrows;
  }

  @Override
  public final void addTearDown(TearDown tearDown) {
    synchronized (lock) {
      stack.addFirst(checkNotNull(tearDown));
    }
  }

    // TODO: verify contents afterward
    // TODO: something shiny and new instead of Stack
    // TODO: test whether null is supported (create a Feature)
    /**
     * The elements to be returned by future calls to {@code next()}, with the first at the top of
     * the stack.
     */
    final Stack<E> nextElements = new Stack<>();

    /**

  private static class FakeExecutor implements Executor {
    Queue<Runnable> tasks = Queues.newArrayDeque();

    @Override
    public void execute(Runnable command) {
      tasks.add(command);
    }

    boolean hasNext() {
      return !tasks.isEmpty();
    }

    void runNext() {
      assertTrue("expected at least one task to run", hasNext());
      tasks.remove().run();
    }

    void runAll() {