@CollectionFeature.Require(SUPPORTS_ADD)
  @CollectionSize.Require(absent = ZERO)
  public void testAdd_supportedPresent() {
    assertFalse("add(present) should return false", getSet().add(e0()));
    expectUnchanged();
  }

  @CollectionFeature.Require(value = {SUPPORTS_ADD, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = ZERO)
  public void testAdd_supportedNullPresent() {

public class SetMultimapPutTester<K, V> extends AbstractMultimapTester<K, V, SetMultimap<K, V>> {
  // Tests for non-duplicate values are in MultimapPutTester

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)
  public void testPutDuplicateValuePreservesSize() {
    assertFalse(multimap().put(k0(), v0()));
    assertEquals(getNumElements(), multimap().size());
  }

  @MapFeature.Require(SUPPORTS_PUT)

public class SetMultimapPutTester<K, V> extends AbstractMultimapTester<K, V, SetMultimap<K, V>> {
  // Tests for non-duplicate values are in MultimapPutTester

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(absent = ZERO)
  public void testPutDuplicateValuePreservesSize() {
    assertFalse(multimap().put(k0(), v0()));
    assertEquals(getNumElements(), multimap().size());
  }

  @MapFeature.Require(SUPPORTS_PUT)

   * tags are computed.
   */
  fun <T> tag(type: Class<out T>): T?

  /**
   * Returns the tag attached with [type] as a key. If it is absent, then [computeIfAbsent] is
   * called and that value is both inserted and returned.
   *
   * If multiple calls to this function are made concurrently with the same [type], multiple values

  public void testLast() {
    assertEquals(c.getKey(), navigableMap.lastKey());
  }

  @CollectionSize.Require(absent = ZERO)
  public void testHeadMapExclusive() {
    assertFalse(navigableMap.headMap(a.getKey()).containsKey(a.getKey()));
  }

  @CollectionSize.Require(absent = ZERO)
  public void testTailMapInclusive() {
    assertTrue(navigableMap.tailMap(a.getKey()).containsKey(a.getKey()));
  }

  public void testKeySet() {
    for (Entry<K, V> entry : getSampleElements()) {
      assertTrue(multimap().keySet().contains(entry.getKey()));
    }
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(ALLOWS_NULL_KEYS)
  public void testKeySetContainsNullKeyPresent() {
    initMultimapWithNullKey();
    assertTrue(multimap().keySet().contains(null));
  }

        expectedHashCode,
        getMap().hashCode());
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  @MapFeature.Require(ALLOWS_NULL_KEYS)
  public void testHashCode_containingNullKey() {
    Entry<K, V> entryWithNull = entry(null, v3());
    runEntryWithNullTest(entryWithNull);
  }

  @CollectionSize.Require(absent = CollectionSize.ZERO)
  @MapFeature.Require(ALLOWS_NULL_VALUES)

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@IgnoreJRERequirement // We opt into library desugaring for our tests.
public class CollectionForEachTester<E> extends AbstractCollectionTester<E> {
  @CollectionFeature.Require(absent = KNOWN_ORDER)
  public void testForEachUnknownOrder() {
    List<E> elements = new ArrayList<>();
    collection.forEach(elements::add);
    Helpers.assertEqualIgnoringOrder(asList(createSamplesArray()), elements);
  }

  public void testToArray_noArg() {
    Object[] actual = getList().toArray();
    assertArrayEquals("toArray() order should match list", createOrderedArray(), actual);
  }

  @CollectionSize.Require(absent = ZERO)
  public void testToArray_tooSmall() {
    Object[] actual = getList().toArray(new Object[0]);
    assertArrayEquals("toArray(tooSmall) order should match list", createOrderedArray(), actual);
  }

  public void testOffer_nullSupported() {
    assertTrue("offer(null) should return true", getQueue().offer(null));
    expectAdded((E) null);
  }

  @CollectionFeature.Require(value = SUPPORTS_ADD, absent = ALLOWS_NULL_VALUES)
  public void testOffer_nullUnsupported() {
    assertThrows(NullPointerException.class, () -> getQueue().offer(null));
    expectUnchanged();