new TestEnumSetGenerator() {
              @Override
              public Set<AnEnum> create(AnEnum[] elements) {
                return (elements.length == 0)
                    ? EnumSet.noneOf(AnEnum.class)
                    : EnumSet.copyOf(MinimalCollection.of(elements));
              }
            })
        .named("EnumSet")
        .withFeatures(
            SetFeature.GENERAL_PURPOSE,

        .onClose(streamB::close);
  }

  /**
   * Invokes {@code consumer} once for each pair of <i>corresponding</i> elements in {@code streamA}
   * and {@code streamB}. If one stream is longer than the other, the extra elements are silently
   * ignored. Elements passed to the consumer are guaranteed to come from the same position in their
   * respective source streams. For example:
   *
   * {@snippet :

  }

  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);

    }

    /**
     * Adds an element to the beginning of a sequenced collection.
     *
     * @param <E> the element type
     * @param collection the sequenced collection
     * @param element the element to add
     * @since Java 21
     */
    public static <E> void addFirst(final SequencedCollection<E> collection, final E element) {
        collection.addFirst(element);
    }

    /**

 * <i>lesser</i> are considered to refer to the comparator on the elements, and the terms
 * <i>first</i> and <i>last</i> are considered to refer to the elements' ordering in a list.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
final class SortedLists {
  private SortedLists() {}

  /**
   * A specification for which index to return if the list contains at least one element that
   * compares as equal to the key.
   */

  }

  protected void expectMissingKeys(K... elements) {
    for (K element : elements) {
      assertFalse("Should not contain key " + element, getMap().containsKey(element));
    }
  }

  protected void expectMissingValues(V... elements) {
    for (V element : elements) {
      assertFalse("Should not contain value " + element, getMap().containsValue(element));
    }
  }

  /**

    return new LexicographicalOrdering<S>(checkNotNull(comparator));
  }

  /**
   * Returns {@code true} if each element in {@code iterable} after the first is greater than or
   * equal to the element that preceded it, according to the specified comparator. Note that this is
   * always true when the iterable has fewer than two elements.
   */
  public static <T extends @Nullable Object> boolean isInOrder(

  @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(

    return new Strings();
  }

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

  protected abstract Collection<String> create(String[] elements);

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

    return new Strings();
  }

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

  protected abstract Queue<String> create(String[] elements);

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