ASP.NET MVC: Mock controller.Url.Action

Question

Urls for menus in my ASP.NET MVC apps are generated from controller/actions. So, they call

controller.Url.Action(action, controller)

Now, h

Answer 1

Here's how you could mock UrlHelper using MvcContrib's TestControllerBuilder:

var routes = new RouteCollection();
MvcApplication.RegisterRoutes(routes);
HomeController controller = CreateController<HomeController>();

controller.HttpContext.Response
    .Stub(x => x.ApplyAppPathModifier("/Home/About"))
    .Return("/Home/About");

controller.Url = new UrlHelper(
    new RequestContext(
        controller.HttpContext, new RouteData()
    ), 
    routes
);
var url = controller.Url.Action("About", "Home");
Assert.IsFalse(string.IsNullOrEmpty(url));

Answer 2

Here is another way to solve the problem with NSubstitute. Hope, it helps someone.

// _accountController is the controller that we try to test
var urlHelper = Substitute.For<UrlHelper>();
urlHelper.Action(Arg.Any<string>(), Arg.Any<object>()).Returns("/test_Controller/test_action");

var context = Substitute.For<HttpContextBase>();
_accountController.Url = urlHelper;
_accountController.ControllerContext = new ControllerContext(context, new RouteData(), _accountController);

Answer 3

A cleaner way to do this is just use Moq(or any other framework you like) to Mock UrlHelper itself

var controller = new OrdersController();
var UrlHelperMock = new Mock<UrlHelper>();

controller.Url = UrlHelperMock.Object;

UrlHelperMock.Setup(x => x.Action("Action", "Controller", new {parem = "test"})).Returns("testUrl");

var url = controller.Url.Action("Action", "Controller", new {parem = "test"});
assert.areEqual("/Controller/Action/?parem=test",url);

clean and simple.

Answer 4

Fake it easy works nicely:

 var fakeUrlHelper = A.Fake<UrlHelper>();
        controller.Url = fakeUrlHelper;
        A.CallTo(() => fakeUrlHelper.Action(A<string>.Ignored, A<string>.Ignored))
            .Returns("/Action/Controller");

Answer 5

If you're using Moq (and not MvcContrib's TestControllerBuilder), you can mock out the context, similar to @DarianDimitrov's answer:

var controller = new OrdersController();
var context = new Mock<System.Web.HttpContextBase>().Object;

controller.Url = new UrlHelper(
    new RequestContext(context, new RouteData()),
    new RouteCollection()
);

This doesn't set the controller.HttpContext property, but it does allow Url.Action to execute (and return an empty string -- no mocking required).