}
    }

    this.task = null;
  }

  @Override
  protected @Nullable String pendingToString() {
    InterruptibleTask<?> localTask = task;
    if (localTask != null) {
      return "task=[" + localTask + "]";
    }
    return super.pendingToString();
  }

  @WeakOuter
  private final class TrustedFutureInterruptibleTask extends InterruptibleTask<V> {

  }

  public void testToString_notDone() throws Exception {
    AbstractFuture<Object> testFuture =
        new AbstractFuture<Object>() {
          @Override
          public String pendingToString() {
            return "cause=[Because this test isn't done]";
          }
        };
    assertThat(testFuture.toString())
        .matches(

    this.fallback = null;
  }

  @Override
  protected @Nullable String pendingToString() {
    @RetainedLocalRef ListenableFuture<? extends V> localInputFuture = inputFuture;
    @RetainedLocalRef Class<X> localExceptionType = exceptionType;
    @RetainedLocalRef F localFallback = fallback;
    String superString = super.pendingToString();
    String resultString = "";
    if (localInputFuture != null) {

       * InterruptibleTask itself so that its other subclasses also benefit. (Handling `callable` in
       * InterruptibleTask itself might also eliminate some of the existing boilerplate for, e.g.,
       * pendingToString().)
       */
      CombinedFuture.this.task = null;

      setValue(result);
    }

    @Override
    final void afterRanInterruptiblyFailure(Throwable error) {

      setStackTrace(new StackTraceElement[0]);
      return this; // no stack trace, wouldn't be useful anyway
    }
  }

  @Override
  protected @Nullable String pendingToString() {
    @RetainedLocalRef ListenableFuture<? extends V> localInputFuture = delegateRef;
    @RetainedLocalRef ScheduledFuture<?> localTimer = timer;
    if (localInputFuture != null) {

     * again if some outstanding input fails.
     */
  }

  @Override
  protected final @Nullable String pendingToString() {
    @RetainedLocalRef ImmutableCollection<? extends Future<?>> localFutures = futures;
    if (localFutures != null) {
      return "futures=" + localFutures;
    }
    return super.pendingToString();
  }

  /**
   * Must be called at the end of each subclass's constructor. This method performs the "real"

   *
   * @return null if an explanation cannot be provided (e.g. because the future is done).
   * @since 23.0
   */
  protected @Nullable String pendingToString() {
    // TODO(diamondm) consider moving this into addPendingString so it's always in the output
    if (this instanceof ScheduledFuture) {

      @RetainedLocalRef ListenableFuture<V> localDelegate = delegate;
      if (localDelegate != null) {
        setFuture(localDelegate);
      }
    }

    @Override
    protected @Nullable String pendingToString() {
      @RetainedLocalRef ListenableFuture<V> localDelegate = delegate;
      if (localDelegate != null) {
        return "delegate=[" + localDelegate + "]";
      }
      return null;
    }

           * https://github.com/google/guava/issues/3553)
           */
          throw t;
        }
      }

      @Override
      protected String pendingToString() {
        return "task=[" + delegate + "]";
      }
    }
  }

  /*
   * This following method is a modified version of one found in