Spliterator.SIZED | Spliterator.DISTINCT | Spliterator.NONNULL,
                    7))
        .expect('a', 'b', 'c', 'd', 'e', 'f', 'g');
  }

  public void testFlatMap_nullStream() {
    SpliteratorTester.of(
            () ->
                CollectSpliterators.flatMap(
                    Arrays.spliterator(new String[] {"abc", "", "de", "f", "g", ""}),

  }

  Set<Cell<R, C, V>> createCellSet() {
    return new CellSet();
  }

  abstract Iterator<Table.Cell<R, C, V>> cellIterator();

  Spliterator<Table.Cell<R, C, V>> cellSpliterator() {
    return Spliterators.spliterator(cellSet(), Spliterator.NONNULL | Spliterator.DISTINCT);
  }

  @WeakOuter
  private final class CellSet extends AbstractSet<Cell<R, C, V>> {
    @Override

      return Sets.equalsImpl(this, obj);
    }
  }

  abstract Iterator<Entry<K, V>> entryIterator();

  Spliterator<Entry<K, V>> entrySpliterator() {
    return Spliterators.spliterator(
        entryIterator(), size(), (this instanceof SetMultimap) ? Spliterator.DISTINCT : 0);
  }

  @LazyInit private transient @Nullable Set<K> keySet;

  @Override
  public Set<K> keySet() {

    initCollectionWithNullElement();
    assertFalse(collection.spliterator().hasCharacteristics(Spliterator.NONNULL));
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testSpliteratorNotImmutable_collectionAllowsAdd() {
    // If add is supported, verify that IMMUTABLE is not reported.
    assertFalse(collection.spliterator().hasCharacteristics(Spliterator.IMMUTABLE));
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)

                    Spliterator.SIZED | Spliterator.DISTINCT | Spliterator.NONNULL,
                    7))
        .expect('a', 'b', 'c', 'd', 'e', 'f', 'g');
  }

  public void testFlatMap_nullStream() {
    SpliteratorTester.of(
            () ->
                CollectSpliterators.flatMap(
                    Arrays.spliterator(new String[] {"abc", "", "de", "f", "g", ""}),

    initCollectionWithNullElement();
    assertFalse(collection.spliterator().hasCharacteristics(Spliterator.NONNULL));
  }

  @CollectionFeature.Require(SUPPORTS_ADD)
  public void testSpliteratorNotImmutable_collectionAllowsAdd() {
    // If add is supported, verify that IMMUTABLE is not reported.
    assertFalse(collection.spliterator().hasCharacteristics(Spliterator.IMMUTABLE));
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)

  }

  @Override
  @GwtIncompatible // Spliterator
  Spliterator<Entry<K, V>> entrySpliterator() {
    return CollectSpliterators.map(
        delegate.entrySet().spliterator(),
        Spliterator.DISTINCT | Spliterator.ORDERED | Spliterator.IMMUTABLE | Spliterator.NONNULL,
        Maps::unmodifiableEntry);
  }

  @Override

    int expectedCharacteristics =
        Spliterator.DISTINCT | Spliterator.ORDERED | Spliterator.NONNULL | Spliterator.IMMUTABLE;
    Spliterator<Entry<AnEnum, String>> spliterator =
        immutableEnumMap(ImmutableMap.of(AnEnum.A, "a", AnEnum.B, "b")).entrySet().spliterator();
    Truth.assertWithMessage(spliterator.getClass().toString())
        .that(spliterator.characteristics() & expectedCharacteristics)

      }

      @Override
      @GwtIncompatible // Spliterator
      public Spliterator<Entry<Class<? extends @NonNull B>, B>> spliterator() {
        return CollectSpliterators.map(
            delegate().spliterator(),
            Spliterator.DISTINCT | Spliterator.NONNULL,
            MutableClassToInstanceMap::checkedEntry);
      }

      @Override

    // The fake cast to E is safe because the creation methods only allow E's
    return (UnmodifiableListIterator<E>) Iterators.forArrayWithPosition(array, index);
  }

  @Override
  public Spliterator<E> spliterator() {
    return Spliterators.spliterator(array, SPLITERATOR_CHARACTERISTICS);
  }

  // TODO(lowasser): benchmark optimizations for equals() and see if they're worthwhile

  // redeclare to help optimizers with b/310253115