unit test user.identity.getuserid asp.net mvc - asp.net-mvc

Question

I have a controller in which I am unit testing my Index action. I am having problem in unit testing User.Identity.GetUserId()
This is my controller
public ActionResult Index()
{
string userId = User.Identity.GetUserId();
DemoModel demoModel = _demoModelService.GetByUserId(userId);
MyModel myModel = new MyModel()
{
Name = demoModel.Name;
Description = demoModel.Description;
}
return View(myModel);
}
This is my Unit Test:
public void Test_Index_Action()
{
//Act
var result = controller.Index() as ViewResult;
//Assert
Assert.AreEqual("", result.ViewName);
}
When I debug my test method, as it reaches the first line of code(User.Identity.GetUserId) of my Index action, it generates null UserId. How can I access the userId in unit testing this code?

Answer 1

I've been struggeling with mvc unit test my self, while there are known techniques to improve testability of your mvc application, most of the projects I worked on are sadly not following them.
So I decided to start this project to help me and others who love to unit test their mvc application. Please take a look at: https://github.com/ibrahimbensalah/Xania.AspNet.Simulator.
Here is an example unit test class
using System.Web.Mvc;
using NUnit.Framework;
using Xania.AspNet.Simulator;
public class SimulatorTests
{
[Test]
public void ActionExecuteTest()
{
// arange
var controller = new TestController();
// act
var result = controller.Execute(c => c.Index());
// assert
Assert.AreEqual("Hello Simulator!", result.ViewBag.Title);
}
[Test]
public void UnAuthorizedActionTest()
{
// arrange
var controller = new TestController();
// act
var result = controller.Execute(c => c.UserProfile());
// assert
Assert.IsInstanceOf<HttpUnauthorizedResult>(result.ActionResult);
}
[Test]
public void AuthorizedActionTest()
{
// arrange
var controller = new TestController();
// act
var result = controller.Action(c => c.UserProfile()).Authenticate("user", null).Execute();
// assert
Assert.IsInstanceOf<ViewResult>(result.ActionResult);
}
}
public class TestController : Controller
{
public ActionResult Index()
{
ViewBag.Title = "Hello Simulator!";
return View();
}
[Authorize]
public ActionResult UserProfile()
{
return View();
}
}