* <li>{@link #ROLES} - The roles field.</li>
 * <li>{@link #FIELDS} - The fields field.</li>
 * <li>{@link #LANGUAGES} - The languages field.</li>
 * <li>{@link #ARRAY_KEY} - The key for array elements.</li>
 * <li>{@link #ARRAY_VALUE} - The value for array elements.</li>
 * <li>{@link #ANALYZER_SETTINGS_TYPE} - The analyzer settings type field.</li>
 * <li>{@link #ANALYZER_SETTINGS_FIELD_NAME} - The analyzer settings field name.</li>

import org.jspecify.annotations.Nullable;

/**
 * Creates queues, containing sample elements, to be tested.
 *
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public interface TestQueueGenerator<E extends @Nullable Object> extends TestCollectionGenerator<E> {
  @Override
  Queue<E> create(Object... elements);

    return Sets.newTreeSet(contents);
  }

  @Override
  NavigableSet<Integer> filter(
      NavigableSet<Integer> elements, Predicate<? super Integer> predicate) {
    return Sets.filter(elements, predicate);
  }

- If there is an existing translation, and it has ADDITIONAL abbr elements in a sentence, and these additional abbr elements do not exist in the related sentence in the English text, then KEEP those additional abbr elements in the translation. Do not remove them. Except when you remove the whole sentence from the translation, because the whole sentence was removed from the English text, then also remove the abbr element. The reasoning for this rule is, that such additional abbr elements are...

    return new TestEnumMultisetGenerator() {
      @Override
      protected Multiset<AnEnum> create(AnEnum[] elements) {
        return (elements.length == 0)
            ? EnumMultiset.create(AnEnum.class)
            : EnumMultiset.create(asList(elements));
      }
    };
  }

  private enum Color {
    BLUE,
    RED,
    YELLOW,
    GREEN,
    WHITE
  }

  @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(

  public SampleElements<Entry<K, V>> samples() {
    return SampleElements.mapEntries(keys, values);
  }

  @Override
  public Set<Entry<K, V>> create(Object... elements) {
    Entry<K, V>[] entries = createArray(elements.length);
    arraycopy(elements, 0, entries, 0, elements.length);
    return createFromEntries(entries);
  }

  public abstract Set<Entry<K, V>> createFromEntries(Entry<K, V>[] entries);

  @Override

  @Override
  Set<Integer> createUnfiltered(Iterable<Integer> contents) {
    return newHashSet(contents);
  }

  @Override
  Set<Integer> filter(Set<Integer> elements, Predicate<? super Integer> predicate) {
    return Sets.filter(elements, predicate);
  }

  /**
   * A collector that converts a stream of zero or one elements to an {@code Optional}.
   *
   * @throws IllegalArgumentException if the stream consists of two or more elements.
   * @throws NullPointerException if any element in the stream is {@code null}.
   * @return {@code Optional.of(onlyElement)} if the stream has exactly one element (must not be
   *     {@code null}) and returns {@code Optional.empty()} if it has none.

  public static Test suite() {
    return SetTestSuiteBuilder.using(
            new TestStringSetGenerator() {
              @Override
              protected Set<String> create(String[] elements) {
                return MinimalSet.of(elements);
              }
            })
        .named("MinimalSet")
        .withFeatures(
            CollectionFeature.ALLOWS_NULL_VALUES, CollectionFeature.NONE, CollectionSize.ANY)