private static Basket GetBasketInstance()
{
var discountFactory = new DiscountRuleFactory();
var calculator = new BasketPriceCalculator(discountFactory);
return(new Basket(calculator));
}
public void BasketCalculatorShouldCorrectlyCalculateFinalOutput()
{
var products = new[] { "Apples", "Milk", "Bread" };
var basketBuilder = new Mock <IBasketBuilder>();
var discountType = new Offer {
DiscountCode = "TenPercentOff", DiscountDetail = "Apples 10% off", ProductId = 1
};
var basketItems = new List <BasketItem>
{
new BasketItem
{
ProductId = 1,
OfferType = discountType,
NumberOfItems = 1,
PricePerItem = 100
},
new BasketItem
{
ProductId = 2,
OfferType = null,
NumberOfItems = 1,
PricePerItem = 130,
},
new BasketItem
{
OfferType = null,
ProductId = 3,
NumberOfItems = 1,
PricePerItem = 80
}
};
basketBuilder.Setup(builder => builder.Build(products)).Returns(
basketItems
);
var discountCalculator = new Mock <IDiscountCalculator>();
var validDiscounts = new List <ValidDiscount>
{
new ValidDiscount
{
DiscountAmount = 10.0m,
OfferType = discountType
}
};
discountCalculator.Setup(calculator => calculator.GetDiscountsApplied(basketItems)).Returns(
validDiscounts);
var expectedResult = new[]
{
"Subtotal: £3.10",
"Apples 10% off: -10p",
"Total: £3.00"
};
var sut = new BasketPriceCalculator(discountCalculator.Object, basketBuilder.Object);
var actualResult = sut.Calculate(products);
CollectionAssert.AreEqual(expectedResult.ToList(), actualResult.ToList());
}
public void CalculatorSumsRightAmountOnSingleBook()
{
var basket = new Basket();
basket.Add(Book.A);
var basketCalculator = new BasketPriceCalculator(basket, 8m);
var discountedBasketTotal = basketCalculator.CalculateBasketTotal();
Assert.Equal(8m, discountedBasketTotal);
}
public void CalculatorSumsRightAmountOnSingleDistinctGroupOfBooks()
{
var basket = new Basket();
basket.Add(Book.A);
basket.Add(Book.B);
basket.Add(Book.C);
basket.Add(Book.D);
basket.Add(Book.E);
var basketCalculator = new BasketPriceCalculator(basket, 8m);
var discountedBasketTotal = basketCalculator.CalculateBasketTotal();
Assert.Equal(30m, discountedBasketTotal);
}
public void GivenBasketItem_Percentage_WhenApplyDiscount_ThenItemIsUpdatedCorrectly()
{
var discountFactory = new DiscountRuleFactory();
var calculator = new BasketPriceCalculator(discountFactory);
var item = new BasketItem
{
Quantity = 2,
AfterDiscountPrice = 0,
DiscountParameter = 10,
DiscountRuleType = DiscountRuleType.Percentage,
Product = new Product
{
Price = (decimal)20.10
}
};
calculator.ApplyDiscount(item);
Assert.AreEqual(36.18, item.AfterDiscountPrice);
}
public void GivenBasketItem_Buy2Get1Free_WhenApplyDiscount_ThenItemIsUpdatedCorrectly()
{
var discountFactory = new DiscountRuleFactory();
var calculator = new BasketPriceCalculator(discountFactory);
var item = new BasketItem
{
Quantity = 3,
AfterDiscountPrice = (decimal)10.50,
DiscountRuleType = DiscountRuleType.BuyManyGetOneFree,
DiscountParameter = 3,
Product = new Product
{
Price = (decimal)10.50
}
};
calculator.ApplyDiscount(item);
Assert.AreEqual(21, item.AfterDiscountPrice);
}
public void GivenBasketItems_WhenCalculateTotal_ThenReturnsCorrectTotal()
{
var discountFactory = new DiscountRuleFactory();
var calculator = new BasketPriceCalculator(discountFactory);
var item = new BasketItem
{
Quantity = 2,
AfterDiscountPrice = (decimal)10.50,
DiscountRuleType = DiscountRuleType.BuyManyGetOneFree,
DiscountParameter = 2,
Product = new Product
{
Price = (decimal)10.50
}
};
var items = Enumerable.Repeat(item, 3);
var total = calculator.CalculateTotal(items);
Assert.AreEqual(31.50, total);
}
