public static void IsIntersectWith_Test57()
        {
            ValueItem itemn4 = new ValueItem(-4, -4);
            ValueItem itemn3 = new ValueItem(-3, -3);
            ValueItem itemn2 = new ValueItem(-2, -2);
            ValueItem itemn1 = new ValueItem(-1, -1);
            ValueItem item1  = new ValueItem(1, 1);
            ValueItem item2  = new ValueItem(2, 2);
            ValueItem item3  = new ValueItem(3, 3);
            ValueItem item4  = new ValueItem(4, 4);

            HashSet <IEnumerable> itemhs1   = new HashSet <IEnumerable>(new ValueItem[] { item1, item2, item3, item4 });
            HashSet <IEnumerable> itemhs2   = new HashSet <IEnumerable>(new ValueItem[] { itemn1, itemn2, itemn3, itemn4 });
            HashSet <IEnumerable> inneritem = new HashSet <IEnumerable>();

            HashSet <HashSet <IEnumerable> >     hashSet;
            IEnumerable <HashSet <IEnumerable> > other;

            SetCollectionComparerTests.SetupTest15(out hashSet, out other);
            inneritem.Add(hashSet);
            hashSet.IntersectWith(other);

            HashSet <IEnumerable>[] expected = new HashSet <IEnumerable>[] { itemhs1, itemhs2, inneritem };
            HashSet <IEnumerable>[] actual   = new HashSet <IEnumerable> [3];
            hashSet.CopyTo(actual, 0, 3);

            Assert.Equal(3, hashSet.Count); //"Should be equal"
            HashSetTestSupport.HashSetContains(actual, expected);
        }
        public static void IsExceptWith_Test57()
        {
            HashSet <HashSet <IEnumerable> >     hashSet;
            IEnumerable <HashSet <IEnumerable> > other;

            SetCollectionComparerTests.SetupTest15(out hashSet, out other);
            hashSet.ExceptWith(other);

            HashSetTestSupport <HashSet <IEnumerable> > .VerifyHashSet(hashSet, new HashSet <IEnumerable> [0], hashSet.Comparer);
        }