}
      }
    }
  }

  /**
   * Call the non-timed {@link Future#get()} in a way that allows us to abort if it's expected to
   * hang forever. More precisely, if it's expected to return, we simply call it[*], but if it's
   * expected to hang (because one of the input futures that we know makes it up isn't done yet),
   * then we call it in a separate thread (using pseudoTimedGet). The result is that we wait as long

          return ImmutableSet.of().iterator();
        }
      };

  /** Queue that discards all elements. */
  @SuppressWarnings("unchecked") // impl never uses a parameter or returns any non-null value
  static <E> Queue<E> discardingQueue() {
    return (Queue) DISCARDING_QUEUE;
  }

  /*
   * Note: All of this duplicate code sucks, but it saves a lot of memory. If only Java had mixins!

  }

  private void checkLogged(Throwable t) {
    assertSame(t, popLoggedThrowable());
  }

  /*
   * TODO(cpovirk): Can we replace makeLocalCache with a call to builder.build()? Some tests may
   * need access to LocalCache APIs, but maybe we can at least make makeLocalCache use
   * builder.build() and then cast?
   */

  private static <K, V> LocalCache<K, V> makeLocalCache(

  }

  private void checkLogged(Throwable t) {
    assertSame(t, popLoggedThrowable());
  }

  /*
   * TODO(cpovirk): Can we replace makeLocalCache with a call to builder.build()? Some tests may
   * need access to LocalCache APIs, but maybe we can at least make makeLocalCache use
   * builder.build() and then cast?
   */

  private static <K, V> LocalCache<K, V> makeLocalCache(

        }
      }
    }
  }

  /**
   * Call the non-timed {@link Future#get()} in a way that allows us to abort if it's expected to
   * hang forever. More precisely, if it's expected to return, we simply call it[*], but if it's
   * expected to hang (because one of the input futures that we know makes it up isn't done yet),
   * then we call it in a separate thread (using pseudoTimedGet). The result is that we wait as long

     *     {@link #whenAllComplete(Iterable)} or {@link #whenAllComplete(Iterable)}
     * @throws IllegalStateException if called outside of a call to {@link
     *     CombiningCallable#call(DeferredCloser, Peeker)} or {@link
     *     AsyncCombiningCallable#call(DeferredCloser, Peeker)}
     */
    @ParametricNullness
    public final <D extends @Nullable Object> D getDone(ClosingFuture<D> closingFuture)

          return ImmutableSet.of().iterator();
        }
      };

  /** Queue that discards all elements. */
  @SuppressWarnings("unchecked") // impl never uses a parameter or returns any non-null value
  static <E> Queue<E> discardingQueue() {
    return (Queue) DISCARDING_QUEUE;
  }

  /*
   * Note: All of this duplicate code sucks, but it saves a lot of memory. If only Java had mixins!

   *
   * <p>Since this method uses {@code TreeMap} instances internally, the keys of the right map must
   * all compare as distinct according to the comparator of the left map.
   *
   * <p><b>Note:</b>If you only need to know whether two sorted maps have the same mappings, call
   * {@code left.equals(right)} instead of this method.
   *
   * @param left the map to treat as the "left" map for purposes of comparison