"Should not contain null key after unsupported putIfAbsent(null, value)");
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUES)
  public void testPutIfAbsent_nullValueUnsupportedAndKeyAbsent() {
    try {
      getMap().putIfAbsent(k3(), null);
      fail("putIfAbsent(key, null) should throw");
    } catch (NullPointerException expected) {
    }
    expectUnchanged();

          fail("Expected IllegalArgumentException");
        } catch (IllegalArgumentException expected) {
        }
      }
    }
    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testSetValueNullUnsupported() {
    for (Entry<K, V> entry : getMap().entrySet()) {
      try {
        entry.setValue(null);

  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(ALLOWS_NULL_VALUES)
  public void testSizeNullValue() {
    initMultimapWithNullValue();
    assertEquals(getNumElements(), multimap().size());
    assertFalse(multimap().isEmpty());
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require({ALLOWS_NULL_KEYS, ALLOWS_NULL_VALUES})
  public void testSizeNullKeyAndValue() {
    initMultimapWithNullKeyAndValue();

  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(ALLOWS_NULL_VALUES)
  public void testSizeNullValue() {
    initMultimapWithNullValue();
    assertEquals(getNumElements(), multimap().size());
    assertFalse(multimap().isEmpty());
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require({ALLOWS_NULL_KEYS, ALLOWS_NULL_VALUES})
  public void testSizeNullKeyAndValue() {
    initMultimapWithNullKeyAndValue();

  }

  @MapFeature.Require(ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testContains_nonNullWhenNullContained() {
    initMapWithNullValue();
    assertFalse("containsValue(notPresent) should return false", getMap().containsValue(v3()));
  }

  @MapFeature.Require(ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testContains_nullContained() {

    assertTrue(multimap().putAll(source));
    assertTrue(multimap().containsEntry(null, v0()));
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUES)
  public void testPutAllRejectsNullValue() {
    Multimap<K, V> source = getSubjectGenerator().create(Helpers.mapEntry(k0(), null));
    try {
      multimap().putAll(source);

              }
            })
        .named("singleton")
        .withFeatures(
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_VALUES,
            CollectionSize.ONE)
        .suppressing(suppressForSingletonSet())
        .createTestSuite();
  }

  public Test testsForHashSet() {
    return SetTestSuiteBuilder.using(

        (multimap instanceof ArrayListMultimap)
            ? ((ArrayListMultimap<?, ?>) multimap).expectedValuesPerKey
            : DEFAULT_VALUES_PER_KEY);
    putAll(multimap);
  }

  /**
   * Creates a new, empty {@code ArrayList} to hold the collection of values for an arbitrary key.
   */
  @Override
  List<V> createCollection() {
    return new ArrayList<>(expectedValuesPerKey);
  }

  /**

                                int num_values) = 0;
  virtual Status SetAttrTypeList(const char* attr_name, const DataType* values,
                                 int num_values) = 0;
  virtual Status SetAttrBoolList(const char* attr_name,
                                 const unsigned char* values,
                                 int num_values) = 0;
  virtual Status SetAttrShapeList(const char* attr_name, const int64_t** dims,

          fail("Expected IllegalArgumentException");
        } catch (IllegalArgumentException expected) {
        }
      }
    }
    expectUnchanged();
  }

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUES)
  @CollectionSize.Require(absent = ZERO)
  public void testSetValueNullUnsupported() {
    for (Entry<K, V> entry : getMap().entrySet()) {
      try {
        entry.setValue(null);