}

          case CANCELLED:
          case INTERRUPTED:
            throw cancellationExceptionWithCause("Task was cancelled.", exception);

          default:
            throw new IllegalStateException("Error, synchronizer in invalid state: " + state);
        }
      }

      /** Checks if the state is {@link #COMPLETED}, {@link #CANCELLED}, or {@link #INTERRUPTED}. */
      boolean isDone() {

            }

          case CANCELLED:
          case INTERRUPTED:
            throw cancellationExceptionWithCause("Task was cancelled.", exception);

          default:
            throw new IllegalStateException("Error, synchronizer in invalid state: " + state);
        }
      }

      /** Checks if the state is {@link #COMPLETED}, {@link #CANCELLED}, or {@link #INTERRUPTED}. */
      boolean isDone() {

      // before the cancelled future completes, it will synchronously complete both the newFuture
      // from the cancelled operation and its own. This can cause one runnable to queue two tasks,
      // breaking the invariant this method relies on to iteratively run the next task after the
      // previous one completes.
      if (get() == RunningState.CANCELLED) {
        delegate = null;
        sequencer = null;

   * <p>If the call {@code setFuture(delegate)} is accepted and this {@code Future} is later
   * cancelled, cancellation will be propagated to {@code delegate}. Additionally, any call to
   * {@code setFuture} after any cancellation will propagate cancellation to the supplied {@code
   * Future}.
   *
   * <p>Note that, even if the supplied future is cancelled and it causes this future to complete,

    // stop it.
    blockingCallable.waitForStart();

    // This time, cancel the future for the first task. The task remains running, only the future
    // is cancelled.
    future1.cancel(false);

    // Give the second task a chance to (incorrectly) start up while the first task is running.
    // (This is the assertion that fails.)
    assertThat(future2.isDone()).isFalse();

  }

  public void testToString_cancelled() throws Exception {
    assertThat(immediateCancelledFuture().toString()).matches("[^\\[]+\\[status=CANCELLED\\]");
  }

  public void testToString_failed() {
    assertThat(immediateFailedFuture(new RuntimeException("foo")).toString())

        this.scheduledDelegate = scheduledDelegate;
      }

      @Override
      public boolean cancel(boolean mayInterruptIfRunning) {
        boolean cancelled = super.cancel(mayInterruptIfRunning);
        if (cancelled) {
          // Unless it is cancelled, the delegate may continue being scheduled
          scheduledDelegate.cancel(mayInterruptIfRunning);

          /*

   *       Futures#getUnchecked}.
   * </ul>
   *
   * @throws ExecutionException if the computation threw an exception
   * @throws CancellationException if the computation was cancelled
   */
  @CanIgnoreReturnValue
  @ParametricNullness
  public static <V extends @Nullable Object> V getUninterruptibly(Future<V> future)
      throws ExecutionException {
    boolean interrupted = false;

  private static final int MAX_BUSY_WAIT_SPINS = 1000;

  @Override
  public final void run() {
    /*
     * Set runner thread before checking isDone(). If we were to check isDone() first, the task
     * might be cancelled before we set the runner thread. That would make it impossible to
     * interrupt, yet it will still run, since interruptTask will leave the runner value null,
     * allowing the CAS below to succeed.
     */

       * - And this future *has* failed: This method is called only from handleException (through
       *   getOrInitSeenExceptions). handleException tried to call setException and failed, so
       *   either this Future was cancelled (which we ruled out with the isCancelled check above),
       *   or it had already failed. (It couldn't have completed *successfully* or even had