}

    @Override
    public V get(long timeout, TimeUnit unit) {
      throw new AssertionFailedError();
    }

    @Override
    public boolean isCancelled() {
      throw new AssertionFailedError();
    }

    @Override
    public boolean isDone() {
      /*
       * If isDone is true during the call to listenInPoolThread,

      return super.get(timeout, unit);
    }

    @Override
    public final boolean isDone() {
      return super.isDone();
    }

    @Override
    public final boolean isCancelled() {
      return super.isCancelled();
    }

    @Override
    public final void addListener(Runnable listener, Executor executor) {
      super.addListener(listener, executor);
    }

    @CanIgnoreReturnValue

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

    manualExecutorTask[0].run();

    for (Future<?> result : results) {
      if (!result.isCancelled()) {
        result.get(10, SECONDS);
      }
      // TODO(cpovirk): Verify that the cancelled futures are exactly ones that we expect.
    }

    assertThat(logHandler.getStoredLogRecords()).isEmpty();
  }

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

    manualExecutorTask[0].run();

    for (Future<?> result : results) {
      if (!result.isCancelled()) {
        result.get(10, SECONDS);
      }
      // TODO(cpovirk): Verify that the cancelled futures are exactly ones that we expect.
    }

    assertThat(logHandler.getStoredLogRecords()).isEmpty();
  }

    NullService service = new NullService();
    service.startAsync().awaitRunning();
    assertFalse(future.isDone());
    service.stopAsync().awaitTerminated();
    assertTrue(future.isCancelled());
  }

  private class NullService extends AbstractScheduledService {
    @Override
    protected void runOneIteration() throws Exception {}

    @Override
    protected Scheduler scheduler() {

    NullService service = new NullService();
    service.startAsync().awaitRunning();
    assertFalse(future.isDone());
    service.stopAsync().awaitTerminated();
    assertTrue(future.isCancelled());
  }

  private class NullService extends AbstractScheduledService {
    @Override
    protected void runOneIteration() throws Exception {}

    @Override
    protected Scheduler scheduler() {

      @Override
      public boolean cancel(boolean mayInterruptIfRunning) {
        return input.cancel(mayInterruptIfRunning);
      }

      @Override
      public boolean isCancelled() {
        return input.isCancelled();
      }

      @Override
      public boolean isDone() {
        return input.isDone();
      }

      @Override

            // a future that eventually came from immediateFuture(null), this doesn't leak
            // throwables or completion values.
            newFuture.setFuture(oldFuture);
          } else if (outputFuture.isCancelled() && taskExecutor.trySetCancelled()) {
            // If this CAS succeeds, we know that the provided callable will never be invoked,
            // so when oldFuture completes it is safe to allow the next submitted task to

  tensorflow::unwrap(cancellation_manager)->StartCancel();
}

bool TFE_CancellationManagerIsCancelled(
    TFE_CancellationManager* cancellation_manager) {
  return tensorflow::unwrap(cancellation_manager)->IsCancelled();
}

bool TFE_CancellationManagerIsCancelling(
    TFE_CancellationManager* cancellation_manager) {
  return tensorflow::unwrap(cancellation_manager)->IsCancelling();
}