public void Can_create_new_transaction()
        {
            var item = new Item
            {
                Value = 567.78M,
                Description = "Add Test",
                IsVerified = true,
            };

            var transaction = new Transaction {
                BusinessKey = 1,
                Date = new DateTime(2009, 11, 15),
                Description = "Test Transaction",
                IsVerified = true,

            };
            item.SetTransaction(transaction);

            Assert.IsNotNull(transaction);
            Assert.AreEqual(transaction.Id, Guid.Empty);
            Assert.AreEqual(transaction.ItemCount(), 1);
        }
        public void ItemCountReturnsCorrectValues()
        {
            var item = new Item
            {
                Value = 567.78M,
                Description = "Add Test",
                IsVerified = true,
            };

            var item2 = new Item
            {
                Value = 667.78M,
                Description = "Add Test 2",
                IsVerified = false,
            };
            var transaction = new Transaction
            {
                BusinessKey = 1,
                Date = new DateTime(2009, 11, 15),
                Description = "Test Transaction",
                IsVerified = true,

            };
            Assert.AreEqual(transaction.ItemCount(), 0);

            item.SetTransaction(transaction);
            Assert.AreEqual(transaction.ItemCount(), 1);

            item.SetTransaction(transaction);
            Assert.AreEqual(transaction.ItemCount(), 1);

            item2.SetTransaction(transaction);
            Assert.AreEqual(transaction.ItemCount(), 2);

            var transaction2 = new Transaction
            {
                BusinessKey = 1,
                Date = new DateTime(2009, 11, 16),
                Description = "Test Transaction2",
                IsVerified = true,

            };
            Assert.AreEqual(transaction2.ItemCount(), 0);
            item.SetTransaction(transaction2);
            Assert.AreEqual(transaction.ItemCount(), 1);
            Assert.AreEqual(transaction2.ItemCount(), 1);
        }