@NullUnmarked
public class ExecutionSequencerTest extends TestCase {

  ExecutorService executor;

  private ExecutionSequencer serializer;
  private SettableFuture<@Nullable Void> firstFuture;
  private TestCallable firstCallable;

  @Override
  public void setUp() throws Exception {
    executor = newCachedThreadPool();
    serializer = ExecutionSequencer.create();
    firstFuture = SettableFuture.create();

      ListenableFuture<I> input,
      AsyncFunction<? super I, ? extends O> function,
      Executor executor) {
    AsyncTransformFuture<I, O> output = new AsyncTransformFuture<>(input, function);
    input.addListener(output, rejectionPropagatingExecutor(executor, output));
    return output;
  }

  static <I extends @Nullable Object, O extends @Nullable Object> ListenableFuture<O> create(

import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@link ClosingFuture} that exercise {@link
 * ClosingFuture#finishToValueAndCloser(ValueAndCloserConsumer, Executor)}.
 */
@NullUnmarked

        final int numThreads = 10;
        final ExecutorService executor = Executors.newFixedThreadPool(numThreads);
        final CountDownLatch latch = new CountDownLatch(numThreads);
        final AtomicInteger callbackCount = new AtomicInteger(0);

        // Add listeners concurrently from multiple threads
        for (int i = 0; i < numThreads; i++) {
            executor.submit(() -> {
                try {

  }

  public void testNoOpScheduledExecutorShutdown() {
    ListeningScheduledExecutorService executor = TestingExecutors.noOpScheduledExecutor();
    assertFalse(executor.isShutdown());
    assertFalse(executor.isTerminated());
    executor.shutdown();
    assertTrue(executor.isShutdown());
    assertTrue(executor.isTerminated());
  }

  }

  public void testNoOpScheduledExecutorShutdown() {
    ListeningScheduledExecutorService executor = TestingExecutors.noOpScheduledExecutor();
    assertFalse(executor.isShutdown());
    assertFalse(executor.isTerminated());
    executor.shutdown();
    assertTrue(executor.isShutdown());
    assertTrue(executor.isTerminated());
  }

   *
   * @param listener the listener to run when the computation is complete
   * @param executor the executor to run the listener in
   * @throws RejectedExecutionException if we tried to execute the listener immediately but the
   *     executor rejected it.
   */
  void addListener(Runnable listener, Executor executor);

   *
   * @param listener the listener to run when the computation is complete
   * @param executor the executor to run the listener in
   * @throws RejectedExecutionException if we tried to execute the listener immediately but the
   *     executor rejected it.
   */
  void addListener(Runnable listener, Executor executor);

        }
      }
    }
  }

  /**
   * Checks if the executor has been shut down and increments the running task count.
   *
   * @throws RejectedExecutionException if the executor has been previously shutdown
   */
  private void startTask() {
    synchronized (lock) {
      if (shutdown) {
        throw new RejectedExecutionException("Executor already shutdown");
      }
      runningTasks++;
    }
  }

import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@link ClosingFuture} that exercise {@link
 * ClosingFuture#finishToValueAndCloser(ValueAndCloserConsumer, Executor)}.
 */
@NullUnmarked