@Override
      public ListenableFuture<V> apply(X t) {
        throw new AssertionError("Unexpected fallback", t);
      }
    };
  }

  // catchingAsync tests cloned from the old withFallback tests:

  public void testCatchingAsync_inputDoesNotRaiseException() throws Exception {
    AsyncFunction<Throwable, Integer> fallback = unexpectedAsyncFunction();

      @Override
      public ListenableFuture<V> apply(X t) {
        throw new AssertionError("Unexpected fallback", t);
      }
    };
  }

  // catchingAsync tests cloned from the old withFallback tests:

  public void testCatchingAsync_inputDoesNotRaiseException() throws Exception {
    AsyncFunction<Throwable, Integer> fallback = unexpectedAsyncFunction();