public void TestIEnumerable()
        {
            var service = new GameObjectService();

            Assert.IsNotNull(service.GetEntities());

            Assert.AreEqual(0, service.GetEntities().Count());
        }
        public void TestEntities()
        {
            var service = new GameObjectService();

            IEntity entity1 = new TestEntity(service, false);

            Assert.AreEqual(0, service.GetEntities().Count());

            IEntity entity2 = new TestEntity(service, true);

            Assert.AreEqual(1, service.GetEntities().Count());

            var enumerator = service.GetEntities().GetEnumerator();

            enumerator.MoveNext();

            Assert.AreNotSame(entity1, enumerator.Current);

            Assert.AreSame(entity2, enumerator.Current);

            IEntity entity3 = new TestEntity(service, true);

            Assert.AreEqual(2, service.GetEntities().Count());
        }