Testing setting of cookies in an ASP.NET MVC 2 Controller

ControllerCookie_Test.cs

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult ADLogin()
{
	//Delete the cookie passed to this page
	if (!Request.Cookies["_CognitionAuthCheck"] == null)
	{
		HttpCookie myCookie = new HttpCookie("_CognitionAuthCheck");
                myCookie.Expires = DateTime.Now().AddDays(-1D);
                Response.Cookies.Add(myCookie);
	}
}

[Test]
public void if_cookie_exists_then_set_to_expire()
{
	TestControllerBuilder builder = new TestControllerBuilder();
	LoginController controller = new LoginController();
	builder.InitializeController(controller);
	builder.HttpContext.Response.Cookies.Add(new HttpCookie("_CognitionAuthCheck", ""));
	
	RedirectResult result = controller.ADLogin() as RedirectResult;
	
	Assert.IsNotNull(controller.HttpContext.Request.Cookies["_CognitionAuthCheck"]);            
}