testing controller action which returns RedirectToRouteResult

Question

I have an action in my controller:

RedirectToRouteResult Create(UserDTO UserDTO)

Which at some point decides with which HTML to respond after a post request by redirecting to an action:

return ModelState.IsValid ? RedirectToAction("ThanksCreate") : RedirectToAction("Register");

In my unit tests I would like to get hold of the ‘views’ modelstate somehow like this:

var modelState = result.ViewData.ModelState;

Assert.IsFalse( modelState.IsValid );

where ‘result’ (ViewResult) is the result of the action ‘Create’ depending on the submitted DTO. My dilemma is that my action ‘returns’ a RedirectToRouteResult which I thought is quite nice but it might not be testable or is it?

How could I get hold of the ModelState in my scenario? Thanks.

Best wishes,

Christian

enter code here

Answer 1

I updated my answer on your other (related) question. In this scenario, I think it's arguably incorrect to test the model state as it isn't exposed outside the method. Rather, you should use your set up to induce correct/incorrect model state and test that the method has the proper output based on the given set up.