public void AddToCart_ExistingGuidPassed()
{
var cartID = "17b37a88-c502-45a8-84be-b48ecc205a3e";
string id = "e3656e5b-23df-4ced-a7e4-4b066839f54a";
var mockHttpContext = MockHttpSession.setSessionKey(cartID);
_controller.ControllerContext.HttpContext = mockHttpContext.Object;
// Act
_controller.AddtoCart(id, 1);
var okResult = _controller.Get();
var items = Assert.IsType <List <ShoppingCartItemDto> >(okResult.Result);
// Assert
Assert.Equal(2, items.Count);
}