});
    assertFalse(task.isDone());
    Thread thread =
        new Thread(
            new Runnable() {
              @Override
              public void run() {
                try {
                  task.run();
                } finally {
                  exitLatch.countDown();
                }
              }
            });
    thread.start();
    enterLatch.await();

       *
       * 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
       * important for other reasons: run() can still be invoked concurrently in different threads,
       * even with the above null checks.)

    enum ExecutionMode {
        /**
         * Run at the beginning of each build. Kill potentially leaked processes in previous builds.
         * Only kill local Gradle processes (classpath in checkout directory).
         * Not clean up global Gradle processes (i.e. classpath in ~/.gradle/...).
         */
        KILL_LEAKED_PROCESSES_FROM_PREVIOUS_BUILDS,
        /**

   * individually submitted tasks and to collections of tasks submitted via {@code invokeAll} or
   * {@code invokeAny}. In the latter case, tasks will run serially on the calling thread. Tasks are
   * run to completion before a {@code Future} is returned to the caller (unless the executor has
   * been shutdown).
   *

          @Override
          public void run() {}
        };
    final Runnable finishSuccess =
        new Runnable() {
          @Override
          public void run() {
            delayedSuccess.set("b");
          }
        };
    final Runnable finishFailure =
        new Runnable() {
          @Override
          public void run() {

  @Override
  public void setUp() throws Exception {
    if (setUp != null) {
      setUp.run();
    }
  }

  // public so that it can be referenced in generated GWT tests.
  @Override
  public void tearDown() throws Exception {
    if (tearDown != null) {
      tearDown.run();
    }
  }

  // public so that it can be referenced in generated GWT tests.
  public final void init(

            });
    assertFalse(task.isDone());
    Thread thread =
        new Thread(
            new Runnable() {
              @Override
              public void run() {
                try {
                  task.run();
                } finally {
                  exitLatch.countDown();
                }
              }
            });
    thread.start();
    enterLatch.await();

  @SuppressWarnings("unchecked")
  protected B self() {
    return (B) this;
  }

  // Test Data

  private @Nullable G subjectGenerator;
  // Gets run before every test.
  private Runnable setUp;
  // Gets run at the conclusion of every test.
  private Runnable tearDown;

  @CanIgnoreReturnValue
  protected B usingGenerator(G subjectGenerator) {
    this.subjectGenerator = subjectGenerator;

    Runnable setUpRunnable =
        new Runnable() {
          @Override
          public void run() {
            setUp[0] = true;
          }
        };

    boolean[] tearDown = {false};
    Runnable tearDownRunnable =
        new Runnable() {
          @Override
          public void run() {
            tearDown[0] = true;
          }
        };

      // allocation.
      submittedTask =
          new Runnable() {
            @Override
            public void run() {
              task.run();
            }

            @Override
            public String toString() {
              return task.toString();
            }
          };
      queue.add(submittedTask);