public async Task CalculateAsync_WhenNullBasket_ShouldThrowException()
{
//arrange
var salesCalculator = new SaleCalculator(null);
//act
await salesCalculator.CalculateAsync(null);
//assert
}
public async Task CalculateAsync_WithDiscounts_ShouldBeSubtractedFromTheTotal()
{
//arrange
var discounts = new List <Discount>
{
new Discount {
DiscountAmount = 1.20m
},
new Discount {
DiscountAmount = 0.80m
}
};
var mockBasketDiscountProcessor = new Mock <IBasketDiscountProcessor>();
mockBasketDiscountProcessor.Setup(m => m.GetAllDiscountsAsync(It.IsAny <IBasket>()))
.Returns(Task.FromResult(discounts.AsEnumerable()));
var salesCalculator = new SaleCalculator(mockBasketDiscountProcessor.Object);
var basket = new Basket
{
Items = new List <BasketItem> {
new BasketItem {
Id = Guid.NewGuid(), Price = 0.30m
},
new BasketItem {
Id = Guid.NewGuid(), Price = 0.30m
},
new BasketItem {
Id = Guid.NewGuid(), Price = 1.30m
},
new BasketItem {
Id = Guid.NewGuid(), Price = 2.30m
},
}
};
//act
var saleDetails = await salesCalculator.CalculateAsync(basket);
//assert
Assert.AreEqual(saleDetails.Total, basket.Items.Sum(i => i.Price) - discounts.Sum(d => d.DiscountAmount));
}
public async Task CalculateAsync_WhenNoDiscounts_TotalAndSubTotalShouldBeEqual()
{
//arrange
var mockBasketDiscountProcessor = new Mock <IBasketDiscountProcessor>();
mockBasketDiscountProcessor.Setup(m => m.GetAllDiscountsAsync(It.IsAny <IBasket>()))
.Returns(Task.FromResult(
Enumerable.Empty <Discount>()
));
var salesCalculator = new SaleCalculator(mockBasketDiscountProcessor.Object);
var basket = new Basket
{
Items = new List <BasketItem> {
new BasketItem {
Id = Guid.NewGuid(), Price = 0.30m
},
new BasketItem {
Id = Guid.NewGuid(), Price = 0.30m
},
new BasketItem {
Id = Guid.NewGuid(), Price = 1.30m
},
new BasketItem {
Id = Guid.NewGuid(), Price = 2.30m
},
}
};
//act
var saleDetails = await salesCalculator.CalculateAsync(basket);
//assert
Assert.AreEqual(saleDetails.SubTotal, saleDetails.Total);
Assert.AreEqual(saleDetails.Total, basket.Items.Sum(i => i.Price));
}