测试身份验证方法

我目前正在尝试学习单元测试，并且已经在ASP.NET Core中创建了项目，因此我可以在实际示例中学习测试。我想在API控制器中测试用于认证方法的快乐路径，因此它将返回OkObjectResult。

到目前为止我所拥有的。

我想测试的控制器方法

        [AllowAnonymous]
        [HttpPost("authenticate")]
        public IActionResult Authenticate([FromBody]User userParam)
        {
            var user = _userService.Authenticate(userParam.Nickname, 
            userParam.Password).Result;

            if(user == null)
            {
                return BadRequest(
                  new { message = "Username or password is incorrect " }
                );
            }

            return Ok(user);
        }

实现IUserService的类中的Authenticate方法：

public async Task<User> Authenticate(string nickname, string password)
        {
            var user = _repository.User.GetAllUsersAsync().Result.SingleOrDefault(u => u.Nickname == nickname && u.Password == password);

            if(user == null)
            {
                return null;
            }

            var tokenHandler = new JwtSecurityTokenHandler();
            var key = Encoding.ASCII.GetBytes(_appSettings.Secret);
            var tokenDescription = new SecurityTokenDescriptor
            {
                Subject = new ClaimsIdentity(new Claim[]
                {
                    new Claim(ClaimTypes.Name, user.UserId.ToString())
                }),
                Expires = DateTime.UtcNow.AddDays(7),
                SigningCredentials = new SigningCredentials(new SymmetricSecurityKey(key), SecurityAlgorithms.HmacSha256Signature)
            };

            var token = tokenHandler.CreateToken(tokenDescription);
            user.Token = tokenHandler.WriteToken(token);

            try
            {
                await _repository.User.UpdateUserAsync(user);

                user.Password = null;

                return user;
            }
            catch (Exception e)
            {
                return user;
            }

        }

而我的单元测试：

        [Fact]
        public void Authenticate_WhenCalled_ReturnsOk()
        {
            //Arrange
            var mockService = new Mock<IUserService>();
            var user = new User()
            {
                UserId = 4,
                IsAdmin = true,
                Token = "12983912803981",
                IsLogged = true,
                MessagesSent = null,
                MessagesReceived = null,
                Nickname = "test3",
                Password = "Str0ngP@ssword123",
                UserChannels = null
            };

            var controller = new UsersController(_repository, _logger, mockService.Object);

            //Act
            var result = controller.Authenticate(user);

            //Assert
            var okResult = result.Should().BeOfType<OkObjectResult>();
        }

但是，单元测试返回BadRequest，而不是预期的OkObjectResult。这可能意味着该用户实际上为空，并且抛出了BadRequest。我应该模拟存储库而不是IUserService吗？