return singleton(elements[0]);
              }
            })
        .named("singleton")
        .withFeatures(
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_VALUES,
            CollectionSize.ONE)
        .suppressing(suppressForSingletonSet())
        .createTestSuite();
  }

  public Test testsForHashSet() {
    return SetTestSuiteBuilder.using(

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_VALUES})
  public void testSetCount_removeNull_nullSupported() {
    initCollectionWithNullElement();
    assertSetCount(null, 0);
  }

  @CollectionFeature.Require(
      value = {SUPPORTS_ADD, ALLOWS_NULL_VALUES},
      absent = RESTRICTS_ELEMENTS)
  public void testSetCount_addNull_nullSupported() {

  }

  @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(ONE)
  public void testRetainAll_nullSingletonPreviouslySingletonWithNull() {
    initCollectionWithNullElement();
    expectReturnsFalse(nullSingleton);
    expectContents(createArrayWithNullElement());
  }

  @CollectionFeature.Require({SUPPORTS_REMOVE, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = {ZERO, ONE})

                return singletonList(elements[0]);
              }
            })
        .named("singletonList")
        .withFeatures(
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_VALUES,
            CollectionSize.ONE)
        .suppressing(suppressForSingletonList())
        .createTestSuite();
  }

  public Test testsForArraysAsList() {
    return ListTestSuiteBuilder.using(

                    return union(emptySet(), emptySet());
                  }
                })
            .named("empty U empty")
            .withFeatures(CollectionSize.ZERO, CollectionFeature.ALLOWS_NULL_VALUES)
            .createTestSuite());

    suite.addTest(
        SetTestSuiteBuilder.using(
                new TestStringSetGenerator() {
                  @Override

    Set<Feature<?>> result = computeDerivedCollectionFeatures(multimapFeatures);
    if (multimapFeatures.contains(MapFeature.ALLOWS_NULL_VALUES)) {
      result.add(CollectionFeature.ALLOWS_NULL_VALUES);
    }
    if (multimapFeatures.contains(MapFeature.ALLOWS_NULL_VALUE_QUERIES)) {
      result.add(CollectionFeature.ALLOWS_NULL_QUERIES);
    }
    return result;
  }

                return singleton(elements[0]);
              }
            })
        .named("singleton")
        .withFeatures(
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_VALUES,
            CollectionSize.ONE)
        .suppressing(suppressForSingletonSet())
        .createTestSuite();
  }

  public Test testsForHashSet() {
    return SetTestSuiteBuilder.using(

              }
            })
        .named("checkedMap/HashMap")
        .withFeatures(
            MapFeature.GENERAL_PURPOSE,
            MapFeature.ALLOWS_NULL_KEYS,
            MapFeature.ALLOWS_NULL_VALUES,
            MapFeature.ALLOWS_ANY_NULL_QUERIES,
            MapFeature.FAILS_FAST_ON_CONCURRENT_MODIFICATION,
            MapFeature.RESTRICTS_KEYS,
            MapFeature.RESTRICTS_VALUES,

              }
            })
        .named("checkedMap/HashMap")
        .withFeatures(
            MapFeature.GENERAL_PURPOSE,
            MapFeature.ALLOWS_NULL_KEYS,
            MapFeature.ALLOWS_NULL_VALUES,
            MapFeature.ALLOWS_ANY_NULL_QUERIES,
            MapFeature.FAILS_FAST_ON_CONCURRENT_MODIFICATION,
            MapFeature.RESTRICTS_KEYS,
            MapFeature.RESTRICTS_VALUES,

  private static final Feature<?>[] FOR_MAP_FEATURES_ONE = {
    CollectionSize.ONE,
    ALLOWS_NULL_VALUES,
    SUPPORTS_REMOVE,
    CollectionFeature.SUPPORTS_ITERATOR_REMOVE
  };

  private static final Feature<?>[] FOR_MAP_FEATURES_ANY = {
    CollectionSize.ANY,
    ALLOWS_NULL_VALUES,
    SUPPORTS_REMOVE,
    CollectionFeature.SUPPORTS_ITERATOR_REMOVE,