How do I write a unit test for controller use automapper? - asp.net-mvc

Question

I'm trying to write a unit test for controller to test method return all users. But I confuse How can I write unit test with automapper
Controller :
private readonly IUserService _userService;
public UserController(IUserService userService)
{
this._userService = userService;
}
public ActionResult List()
{
var users = _userService.GetAllUsers().ToList();
var viewModel = Mapper.Map<List<UserViewModel>>(users);
return View(viewModel);
}
Controller Test:
private Mock<IUserService> _userServiceMock;
UserController objUserController;
List<UserViewModel> listUser;
[SetUp]
public void Initialize()
{
_userServiceMock = new Mock<IUserService>();
objUserController = new UserController(_userServiceMock.Object);
listUser = new List<UserViewModel>()
{
new UserViewModel() {Id = 1, Active = true, Password = "123456", UserName = "hercules"},
new UserViewModel() {Id = 2, Active = false, Password = "1234567", UserName = "alibaba"},
new UserViewModel() {Id = 3, Active = true, Password = "12345678", UserName = "robinhood"},
};
}
[Test]
public void Index_Returns_AllUser()
{
// How do I here ???
}

Answer 1

Configure automapper as you do on your MVC project:
[SetUp]
public void Initialize()
{
....
AutoMapperConfiguration.Configure();
}
Where AutoMapperConfiguration is a public static class like:
public class AutoMapperConfiguration
{
/// <summary>
/// Maps between VIEWMODEL and MODEL
/// </summary>
public static void Configure()
{
//maps here
Mapper.CreateMap..
}
}

Answer 2

You're trying to write a test of little to no value. Don't write this test. Use the real IUserService and use the real AutoMapper and assert against the ViewResult.
I would never unit test this code.
But if you're absolutely bent on writing this unit test, don't mock AutoMapper. Mock the IUserService.
UserController objUserController;
List<User> listUser;
[SetUp]
public void Initialize()
{
var userServiceMock = new Mock<IUserService>();
listUser = new List<User>()
{
new User() {Id = 1, Active = true, Password = "123456", UserName = "hercules"},
new User() {Id = 2, Active = false, Password = "1234567", UserName = "alibaba"},
new User() {Id = 3, Active = true, Password = "12345678", UserName = "robinhood"},
};
userServiceMock.Setup(framework => framework.GetAllUsers())
.Returns(listUser);
objUserController = new UserController(_userServiceMock.Object);
}
[Test]
public void Index_Returns_AllUser()
{
var result = objUserController.List();
var viewResult = result as ViewResult;
viewResult.ShouldNotBe(null);
var model = viewResult.Model as List<UserListModel>;
model.ShouldNotBe(null);
model.Count.ShouldBe(3); // Don't do more than this
}

Answer 3

You can create a wrapper class for automapper with an interface. For example:
public interface IMapperWrapper
{
object Map(object source, Type sourceType, Type destinationType);
}
Then all you need to do in your tests is mock your map.
automapperWrapperMock.Setup(x => x.Map, type, type);

Answer 4

Just setup your controller calling your Automapper configuration and all your tests for that controller will work properly.
[TestInitialize]
public void Setup()
{
controller = new yourController(_unitOfWork.Object, _someRepository.Object)
{
};
AutoMapperConfig.RegisterMappings();
}