public void AddComment() { var controllerContext = new Mock <ControllerContext>(); var principal = new Mock <IPrincipal>(); principal.Setup(p => p.IsInRole("Administrator")).Returns(true); principal.SetupGet(x => x.Identity.Name).Returns("rr"); controllerContext.SetupGet(x => x.HttpContext.User).Returns(principal.Object); controller.ControllerContext = controllerContext.Object; CommentModel toAdd = new CommentModel { AuthorLogin = "******", CreateDate = DateTime.Now, RecipeId = 2, Text = "new comment", Id = 7 }; ViewResult result = controller.AddComment(toAdd) as ViewResult; var addedComment = db.FindComment(7); Assert.AreNotEqual(null, addedComment); }