public async Task <Result> ChangeItemQuantityAsync(string userId, int basketItemId, int quantity)
{
Basket basket = await _basketRepository.GetByUserIdAsync(userId);
if (basket == null)
{
var message = string.Format(ErrorMessage.UserDoesntHaveBasket, userId);
_logger.LogInformation(message);
return(Result.Fail(message));
}
BasketItem item = basket.Items.FirstOrDefault(i => i.Id == basketItemId);
if (item == null)
{
var message = string.Format(ErrorMessage.BasketWithItemIdDoesntExists, basketItemId);
_logger.LogInformation(message);
return(Result.Fail(message));
}
item.ChangeQuantity(quantity);
await _basketRepository.UpdateAsync(basket);
return(Result.Ok());
}
public void ChangeQuantity_WithNegativeQuantity_ShouldThrowContractException()
{
// Arrange
var basketItem = new BasketItem(1, 2, Pounds.Of(3));
Action changeQuantity = () => basketItem.ChangeQuantity(-1);
// Assert
Assert.Throws <ContractException>(changeQuantity);
}
public void ChangeQuantity_WithValidQuantity_ShouldChangeQuantity()
{
// Arrange
var basketItem = new BasketItem(1, 2, Pounds.Of(3));
// Act
basketItem.ChangeQuantity(4);
// Assert
Assert.Equal(4, basketItem.Quantity);
}
