/** Though this executor service may hold many threads, they are not executed concurrently. */
  private val tasksExecutor = Executors.newCachedThreadPool(threadFactory("TaskFaker"))

  /**
   * True if this task faker has ever had multiple tasks scheduled to run concurrently. Guarded by
   * `this`.
   */
  var isParallel = false

  /** Number of calls to [TaskRunner.Backend.execute]. Guarded by `this`. */
  var executeCallCount = 0

      MapMakerInternalMap<K, V, ? extends InternalEntry<K, V, ?>, ? extends Segment<K, V, ?, ?>>
          makeMap(MapMaker maker) {
    return MapMakerInternalMap.create(maker);
  }

  private static MapMaker createMapMaker() {
    MapMaker maker = new MapMaker();
    maker.useCustomMap = true;
    return maker;
  }

  // constructor tests

  public void testDefaults() {

      MapMakerInternalMap<K, V, ? extends InternalEntry<K, V, ?>, ? extends Segment<K, V, ?, ?>>
          makeMap(MapMaker maker) {
    return MapMakerInternalMap.create(maker);
  }

  private static MapMaker createMapMaker() {
    MapMaker maker = new MapMaker();
    maker.useCustomMap = true;
    return maker;
  }

  // constructor tests

  public void testDefaults() {