CODEWITHSUNDEEP
c#asp.net-mvcasp.net-mvc-3unit-testing
Dismissile
Dismissile

Reputation: 33071

Unit Testing Controllers with Url Extensions

I recently changed most of my Controllers to use Url helper extensions instead of using RedirectToAction, etc:

public ActionResult Create(CreateModel model)
{
    // ...
    return Redirect(Url.Home());
}

This has currently made my unit tests break with NullReference exceptions. What is the proper way to mock/stub a UrlHelper so I can get my unit tests working again?

Edit:

My Url extension looks like this:

public static class UrlHelperExtensions
{
    public static string Home(this UrlHelper helper)
    {
        return helper.RouteUrl("Default");
    }
}

My unit test is just testing to make sure that they are redirected to the correct page:

// Arrange
var controller = new HomeController();

// Act
var result = controller.Create(...);

// Assert
// recalling the exact details of this from memory, but this is what i'm trying to do:
Assert.IsInstanceOfType(result, typeof(RedirectToRouteResult));
Assert.AreEqual(((RedirectToRouteResult)result).Controller, "Home");
Assert.AreEqual(((RedirectToRouteResult)result).Action, "Index");

What is happening now is when I call Url.Home() but I get a nullreference error. I tried setting the Url property with a new UrlHelper but it still gets a null reference exception.

Upvotes: 2

Views: 541

Answers (1)

mxmissile
mxmissile

Reputation: 11673

I think your better off abstracting out your extensions for example:

public interface IUrls
{
   string Home();
}

public class Urls : IUrls
{
   public string Home()
   {
       //impl
   }
}

Then constructor inject that wherever needed, then you can easily Stub 'IUrls' for your tests.

Upvotes: 1

Related Questions