Mvcontrib.MVC3.Testhelper UpdateModel NullReferenceExceuption durante Unit Test

Question

Sto tentando di eseguire un test unitario di un'azione di modifica sul mio controller in ASP.NET MVC 3.

Ho installato Mvcontrib.MVC3.TestHelper tramite nuget per simulare il contesto del mio controller ma ricevo ancora una NullReferenceException

il mio codice ha questo aspetto:

 [TestMethod]
    public void it_should_redirect_to_index_after_editing_a_something_successfully()
    {
        var something= new SomeThing
        {
            ID = Guid.NewGuid(),
            CreatedAt = DateTime.Now,
            LastModified = DateTime.Now,
            Owner = "Me",
            Status = "new",
            Title = "my Title",
            Attachments = new List<Attachment>()
        };

        var repo = new FakeRepository();
        var controller = new SomethingsController(repo);
        new TestControllerBuilder().InitializeController(controller);

        var result = controller.Edit(something) as RedirectToRouteResult;
        result.AssertActionRedirect().ToAction<SomethingsController>(x => x.Index());
    }

Il codice di produzione ha questo aspetto ...

 [HttpPost]
    public ActionResult Edit(SomeThing something)
    {
        if (ModelState.IsValid)
        {
            var _something = _repository.GetDocumentByID(something.ID);
            TryUpdateModel(_something);
            _something.LastModified = DateTime.Now;
            _repository.SaveChanges();
            return RedirectToAction("Index","Somethings");
        }
        return View(something);
    }

E anche se utilizzo UpdateModel o TryUpdateModel si verifica sempre un arresto anomalo con una NullReferenceException ...

Qualsiasi aiuto, i suggerimenti sarebbero fantastici ...

Answer 1

Ecco come puoi procedere:

public class Something
{
    public Guid ID { get; set; }
    public DateTime LastModified { get; set; }
    public DateTime CreatedAt { get; set; }
    public string Owner { get; set; }
    public string Status { get; set; }
    public string Title { get; set; }
}

public interface ISomeRepository
{
    Something GetDocumentByID(Guid id);
    void SaveChanges();
}

public class HomeController : Controller
{
    private readonly ISomeRepository _repository;
    public HomeController(ISomeRepository repository)
    {
        _repository = repository;
    }

    public ActionResult Index()
    {
        return View();
    }

    [HttpPost]
    public ActionResult Edit(Something something)
    {
        if (ModelState.IsValid)
        {
            var _something = _repository.GetDocumentByID(something.ID);
            TryUpdateModel(_something);
            _something.LastModified = DateTime.Now;
            _repository.SaveChanges();
            return RedirectToAction("Index", "Home");
        }
        return View(something);
    }
}

e il test:

// arrange
var something = new Something
{
    ID = Guid.NewGuid(),
    CreatedAt = DateTime.Now,
    LastModified = DateTime.Now,
    Owner = "Me",
    Status = "new",
    Title = "my Title",
};
var somethingElse = new Something();
var repo = MockRepository.GenerateStub<ISomeRepository>();
var controller = new HomeController(repo);
new TestControllerBuilder().InitializeController(controller);
repo.Stub(x => x.GetDocumentByID(something.ID)).Return(somethingElse);

var formValues = new FormCollection() 
{
    { "Owner", "some owner" },
};
controller.ValueProvider = formValues.ToValueProvider();

// act
var actual = controller.Edit(something);

// assert
repo.AssertWasCalled(x => x.SaveChanges());
actual
    .AssertActionRedirect()
    .ToAction<HomeController>(x => x.Index());