ChessClient.Tests.Controllers.AccountControllerTest.Register_Post_ReturnsViewIfRegistrationFails C# (CSharp) Method

        public void Register_Post_ReturnsViewIfRegistrationFails()
        {
            // Arrange
            AccountController controller = GetAccountController();
            RegisterModel model = new RegisterModel()
            {
                UserName = "duplicateUser",
                Email = "goodEmail",
                Password = "goodPassword",
                ConfirmPassword = "goodPassword"
            };

            // Act
            ActionResult result = controller.Register(model);

            // Assert
            Assert.IsInstanceOfType(result, typeof(ViewResult));
            ViewResult viewResult = (ViewResult)result;
            Assert.AreEqual(model, viewResult.ViewData.Model);
            Assert.AreEqual("Username already exists. Please enter a different user name.", controller.ModelState[""].Errors[0].ErrorMessage);
            Assert.AreEqual(10, viewResult.ViewData["PasswordLength"]);
        }