output.cancel(false);
        throw new MyRuntimeException();
      }
    }
    Transformer transformer = new Transformer();
    SettableFuture<Object> input = SettableFuture.create();

    ListenableFuture<Object> output = transform(input, transformer, directExecutor());
    transformer.output = output;

    input.set("foo");
    assertTrue(output.isCancelled());
  }

        output.cancel(false);
        throw new MyRuntimeException();
      }
    }
    Transformer transformer = new Transformer();
    SettableFuture<Object> input = SettableFuture.create();

    ListenableFuture<Object> output = transform(input, transformer, directExecutor());
    transformer.output = output;

    input.set("foo");
    assertTrue(output.isCancelled());
  }

          final EntryTransformer<? super K, V1, V2> transformer, @ParametricNullness final K key) {
    checkNotNull(transformer);
    return new Function<V1, V2>() {
      @Override
      @ParametricNullness
      public V2 apply(@ParametricNullness V1 v1) {
        return transformer.transformEntry(key, v1);
      }
    };
  }

  /** Views an entry transformer as a function from {@code Entry} to values. */

   * #finishToValueAndCloser(ValueAndCloserConsumer, Executor)}, or any other derivation method on
   * the original {@code ClosingFuture} instance.
   *
   * @param function transforms the value of this step to the value of the derived step
   * @param executor executor to run the function in
   * @return the derived step