* (unless the executor has been shutdown).
   *
   * <p>The returned executor is backed by the executor returned by {@link
   * MoreExecutors#newDirectExecutorService} and subject to the same constraints.
   *
   * <p>Although all tasks are immediately executed in the thread that submitted the task, this

    ClosingFuture<String> closingFuture =
        ClosingFuture.from(executor.submit(Callables.returning(closeable1)))
            .transform(
                (DeferredCloser closer, TestCloseable v) -> {
                  assertThat(v).isSameInstanceAs(closeable1);
                  return "value";
                },
                executor);
    assertThat(getFinalValue(closingFuture)).isEqualTo("value");

      assertEquals(Service.State.STOPPING, state());
      shutdownCalled++;
    }

    @Override
    protected Executor executor() {
      return executor;
    }

    @Override
    public void tearDown() throws Exception {
      executor.shutdown();
    }
  }

    private final Executor listenerExecutor;

    CombinedFutureInterruptibleTask(Executor listenerExecutor) {
      this.listenerExecutor = checkNotNull(listenerExecutor);
    }

    @Override
    final boolean isDone() {
      return CombinedFuture.this.isDone();
    }

    final void execute() {
      try {
        listenerExecutor.execute(this);

   */
  protected void triggerShutdown() {}

  /**
   * Returns the {@link Executor} that will be used to run this service. Subclasses may override
   * this method to use a custom {@link Executor}, which may configure its worker thread with a
   * specific name, thread group or priority. The returned executor's {@link
   * Executor#execute(Runnable) execute()} method is called when this service is started, and should
   * return promptly.
   *

    List<Future<?>> results = new ArrayList<>();
    Runnable[] manualExecutorTask = new Runnable[1];
    Executor manualExecutor =
        new Executor() {
          @Override
          public void execute(Runnable task) {
            manualExecutorTask[0] = task;
          }
        };

    results.add(serializer.submit(Callables.returning(null), manualExecutor));

            }
          };
      executor.execute(errorTask);
      service.execute(barrierTask); // submit directly to the service
      // the barrier task runs after the error task so we know that the error has been observed by
      // SequentialExecutor by the time the barrier is satisfied
      barrier.await(1, SECONDS);
      executor.execute(barrierTask);
      // timeout means the second task wasn't even tried

  /**
   * Registers a listener to be {@linkplain Executor#execute(Runnable) run} on the given executor.
   * The listener will run when the {@code Future}'s computation is {@linkplain Future#isDone()
   * complete} or, if the computation is already complete, immediately.
   *
   * <p>There is no guaranteed ordering of execution of listeners, but any listener added through

  }

  public void testTimeout() throws Exception {
    // Create a service whose executor will never run its commands
    Service service =
        new TestService() {
          @Override
          protected Executor executor() {
            return new Executor() {
              @Override
              public void execute(Runnable command) {}
            };
          }

          @Override

  public void testFinishToFuture_throwsIfCalledTwice() throws Exception {
    ClosingFuture<Closeable> closingFuture =
        ClosingFuture.submit(closer -> closer.eventuallyClose(mockCloseable, executor), executor);
    FluentFuture<Closeable> unused = closingFuture.finishToFuture();
    assertThrows(
        IllegalStateException.class,
        () -> {
          FluentFuture<Closeable> unused2 = closingFuture.finishToFuture();