30DaysOfTDD_Day21_part0

        [Test]
        public void WhenUserPlacesACorrectOrderWithMoreThenOneItemThenAnOrderNumberShouldBeReturned()
        {
            //Arrange
            var shoppingCart = new ShoppingCart();
            var itemOneId = Guid.NewGuid();
            var itemTwoId = Guid.NewGuid();
            int itemOneQuantity = 1;
            int itemTwoQuantity = 4;
            shoppingCart.Items.Add(new ShoppingCartItem { ItemId = itemOneId, Quantity = itemOneQuantity });            
            shoppingCart.Items.Add(new ShoppingCartItem { ItemId = itemTwoId, Quantity = itemTwoQuantity });
            var customerId = Guid.NewGuid();
            var expectedOrderId = Guid.NewGuid();
            var orderFulfillmentSessionId = Guid.NewGuid();            
            var customer = new Customer { Id = customerId };

            Mock.Arrange(() => _orderDataService.Save(Arg.IsAny<Order>()))
                .Returns(expectedOrderId)
                .OccursOnce();
            Mock.Arrange(() => _customerService.GetCustomer(customerId)).Returns(customer).OccursOnce();
            Mock.Arrange(() => _orderFulfillmentService.OpenSession(Arg.IsAny<string>(), Arg.IsAny<string>()))
                .Returns(orderFulfillmentSessionId);
            Mock.Arrange(() => _orderFulfillmentService.IsInInventory(orderFulfillmentSessionId, itemOneId, itemOneQuantity))
                .Returns(true)
                .OccursOnce();
            Mock.Arrange(() => _orderFulfillmentService.IsInInventory(orderFulfillmentSessionId, itemTwoId, itemTwoQuantity))
                .Returns(true)
                .OccursOnce();
            Mock.Arrange(() =>
                _orderFulfillmentService.
                    PlaceOrder(orderFulfillmentSessionId, Arg.IsAny<IDictionary<Guid, int>>(), Arg.IsAny<string>()))
                .Returns(true);
            //Act
            var result = _orderService.PlaceOrder(customerId, shoppingCart);

            //Assert
            Assert.AreEqual(expectedOrderId, result);
            Mock.Assert(_orderDataService);
            Mock.Assert(_orderFulfillmentService);
        }