if (!parentBuilder.getFeatures().contains(NoRecurse.NO_ENTRY_SET)) {
      derivedSuites.add(
          SetTestSuiteBuilder.using(new EntrySetGenerator<E>(parentBuilder.getSubjectGenerator()))
              .named(getName() + ".entrySet")
              .withFeatures(computeEntrySetFeatures(parentBuilder.getFeatures()))
              .suppressing(parentBuilder.getSuppressedTests())

    int expectedHashCode = 0;
    for (E element : elements) {
      expectedHashCode += ((element == null) ? 0 : element.hashCode());
    }

    elements.add(null);
    collection = getSubjectGenerator().create(elements.toArray());
    assertEquals(
        "A Set's hashCode() should be the sum of those of its elements (with "
            + "a null element counting as having a hash of zero).",
        expectedHashCode,

    if (parentBuilder.getFeatures().contains(SERIALIZABLE)) {
      derivedSuites.add(
          CollectionTestSuiteBuilder.using(
                  new ReserializedCollectionGenerator<E>(parentBuilder.getSubjectGenerator()))
              .named(getName() + " reserialized")
              .withFeatures(computeReserializedCollectionFeatures(parentBuilder.getFeatures()))
              .suppressing(parentBuilder.getSuppressedTests())

  @CollectionSize.Require(absent = {ZERO, ONE})
  public void testCreateWithDuplicates() {
    E[] array = createSamplesArray();
    array[1] = e0();
    collection = getSubjectGenerator().create(array);

    expectContents(array);
  }

    if (parentBuilder.getFeatures().contains(SERIALIZABLE)) {
      derivedSuites.add(
          SetTestSuiteBuilder.using(
                  new ReserializedSetGenerator<E>(parentBuilder.getSubjectGenerator()))
              .named(getName() + " reserialized")
              .withFeatures(computeReserializedCollectionFeatures(parentBuilder.getFeatures()))
              .suppressing(parentBuilder.getSuppressedTests())

  @CollectionFeature.Require(value = {SUPPORTS_ADD, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = ZERO)
  public void testAdd_supportedNullPresent() {
    E[] array = createArrayWithNullElement();
    collection = getSubjectGenerator().create(array);
    assertTrue("add(nullPresent) should return true", getList().add(null));

    List<E> expected = copyToList(array);
    expected.add(null);
    expectContents(expected);
  }

  /**

    if (parentBuilder.getFeatures().contains(SERIALIZABLE)) {
      derivedSuites.add(
          CollectionTestSuiteBuilder.using(
                  new ReserializedCollectionGenerator<E>(parentBuilder.getSubjectGenerator()))
              .named(getName() + " reserialized")
              .withFeatures(computeReserializedCollectionFeatures(parentBuilder.getFeatures()))
              .suppressing(parentBuilder.getSuppressedTests())

  @CollectionSize.Require(absent = {ZERO, ONE})
  public void testRemoveAll_duplicate() {
    ArrayWithDuplicate<E> arrayAndDuplicate = createArrayWithDuplicateElement();
    collection = getSubjectGenerator().create(arrayAndDuplicate.elements);
    E duplicate = arrayAndDuplicate.duplicate;

    assertTrue(
        "removeAll(intersectingCollection) should return true",

  @CollectionSize.Require(absent = {ZERO, ONE})
  public void testRemoveAll_duplicate() {
    ArrayWithDuplicate<E> arrayAndDuplicate = createArrayWithDuplicateElement();
    collection = getSubjectGenerator().create(arrayAndDuplicate.elements);
    E duplicate = arrayAndDuplicate.duplicate;

    assertTrue(
        "removeAll(intersectingCollection) should return true",

public class AbstractMultisetTester<E> extends AbstractCollectionTester<E> {
  protected final Multiset<E> getMultiset() {
    return (Multiset<E>) collection;
  }

  protected void initThreeCopies() {
    collection = getSubjectGenerator().create(e0(), e0(), e0());
  }