public void Test_AreEqual_Product()
        {
            //Arange
            var shopBasket = new ShoppingBasketItem();
            shopBasket.Product = null;

            //Assert
            Assert.IsNull(shopBasket.Product);
        }
        public void Test_AreEqual_AddItemToBasket()
        {
            //Arrange
            var basket = new StoreBasket(20m);
            IShoppingBasketItem shopItem = new ShoppingBasketItem();
            shopItem.LineSum = 20;
            basket.AddItemToBasket(shopItem);

            //Assert
            Assert.AreEqual(basket.Id, 2);
        }
        public void Test_AreEqual_InBasket()
        {
            //Arrang
            var shopBasket = new ShoppingBasketItem();
            shopBasket.InBasket = null;

            //Act
            var actual = shopBasket.InBasket;

            //Assert
            Assert.IsNull(actual);
        }
        public void Test_AreNotEqual_Id()
        {
            //Arrange
            var item = new ShoppingBasketItem();
            item.Id = 1;

            //Act
            var actual = item.Id;
            var expected = 2;

            //Assert
            Assert.AreNotEqual(expected, actual);
        }
        public void Test_AreEqual_Quantity()
        {
            //Arrange
            var item = new ShoppingBasketItem();
            item.Quantity = 3;

            //Act
            var actual = item.Quantity;
            var expected = 3;

            //Assert
            Assert.AreEqual(expected, actual);
        }
        public void Test_AreEqual_LineSum()
        {
            //Arrange
            var item = new ShoppingBasketItem();
            item.LineSum = 30.00m;

            //Act
            var actual = item.LineSum;
            var expected = 30.00m;

            //Assert
            Assert.AreEqual(expected, actual);
        }