}

  public static class Chars extends SampleElements<Character> {
    public Chars() {
      // elements aren't sorted, to better test SortedSet iteration ordering
      super('b', 'a', 'c', 'd', 'e');
    }
  }

  public static class Enums extends SampleElements<AnEnum> {
    public Enums() {
      // elements aren't sorted, to better test SortedSet iteration ordering
      super(AnEnum.B, AnEnum.A, AnEnum.C, AnEnum.D, AnEnum.E);

  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  public void testEquals_containingNull() {
    ArrayList<E> elements = new ArrayList<>(getSampleElements());
    elements.set(elements.size() / 2, null);
    collection = getSubjectGenerator().create(elements.toArray());
    List<E> other = new ArrayList<>(getSampleElements());
    assertFalse(

 * both {@link Collection} and {@link Map}; since there isn't an established collective noun that
 * encompasses both of these, 'container' is used.
 *
 * @author George van den Driessche
 */
@GwtCompatible
@NullMarked
public interface TestContainerGenerator<T, E extends @Nullable Object> {
  /** Returns the sample elements that this generate populates its container with. */

    suite.addTest(
        NavigableSetTestSuiteBuilder.using(
                new TestStringSetGenerator() {
                  @Override
                  protected Set<String> create(String[] elements) {
                    return new SafeTreeSet<>(asList(elements));
                  }

                  @Override
                  public List<String> order(List<String> insertionOrder) {

    implements TestSortedSetGenerator<String> {

  @Override
  public SortedSet<String> create(Object... elements) {
    return (SortedSet<String>) super.create(elements);
  }

  @Override
  protected abstract SortedSet<String> create(String[] elements);

  /** Sorts the elements by their natural ordering. */
  /*
   * While the current implementation returns `this`, that's not something we mean to guarantee.

  protected <E extends Comparable<? super E>> Set<E> copyOf(E[] elements) {
    return ImmutableSet.copyOf(elements);
  }

  @Override
  protected <E extends Comparable<? super E>> Set<E> copyOf(Collection<? extends E> elements) {
    return ImmutableSet.copyOf(elements);
  }

  @Override
  protected <E extends Comparable<? super E>> Set<E> copyOf(Iterable<? extends E> elements) {
    return ImmutableSet.copyOf(elements);
  }

  protected <E extends Comparable<? super E>> Set<E> copyOf(E[] elements) {
    return ImmutableSet.copyOf(elements);
  }

  @Override
  protected <E extends Comparable<? super E>> Set<E> copyOf(Collection<? extends E> elements) {
    return ImmutableSet.copyOf(elements);
  }

  @Override
  protected <E extends Comparable<? super E>> Set<E> copyOf(Iterable<? extends E> elements) {
    return ImmutableSet.copyOf(elements);
  }

        OneSizeTestContainerGenerator<SetMultimap<K, V>, Entry<K, V>> multimapGenerator) {
      super(multimapGenerator);
    }

    @Override
    public Set<Entry<K, V>> create(Object... elements) {
      return (Set<Entry<K, V>>) super.create(elements);
    }
  }

  static final class MultimapGetGenerator<K, V>
      extends MultimapTestSuiteBuilder.MultimapGetGenerator<K, V, SetMultimap<K, V>>

    return new Enums();
  }

  @Override
  public Multiset<AnEnum> create(Object... elements) {
    AnEnum[] array = new AnEnum[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (AnEnum) e;
    }
    return create(array);
  }

  protected abstract Multiset<AnEnum> create(AnEnum[] elements);

  @Override
  public AnEnum[] createArray(int length) {
    return new AnEnum[length];

        SetTestSuiteBuilder.using(
                new TestStringSetGenerator() {
                  @Override
                  protected Set<String> create(String[] elements) {
                    return new StandardImplForwardingSet<>(new LinkedHashSet<>(asList(elements)));
                  }
                })
            .named("ForwardingSet[LinkedHashSet] with standard implementations")
            .withFeatures(