public async Task AddRoleToUser_ReturnsModel_WhenUserDoesntExist()
        {
            //Arrange
            userManager.CurrentRole = RoleType.Standard;
            controller.ControllerContext.HttpContext = new DefaultHttpContext();

            //Act
            var result = await controller.AddRoleToUser("username", RoleType.Administrator.ToString());

            //Assert
            var redirectToActionResult = Assert.IsType <RedirectToActionResult>(result);

            Assert.Equal("Role", redirectToActionResult.ControllerName);
            Assert.Equal("Index", redirectToActionResult.ActionName);
        }