Scala Play + Slick:如何向Spec测试注入依赖项？

trait UserService {
  def getUser(id: Int): Future[Option[User]]
}

class UserServiceImpl extends UserService {
  override def getUser(id: Int): Future[Option[User]] = {
    // 实现获取用户的逻辑
  }
}

class MockUserService extends UserService {
  override def getUser(id: Int): Future[Option[User]] = {
    // 返回模拟的用户数据
  }
}

class UserControllerSpec extends PlaySpec with GuiceOneAppPerTest {
  // 注入依赖项
  val userService: UserService = new MockUserService
  val userController: UserController = new UserController(userService)

  "UserController" should {
    "return user" in {
      // 执行测试代码并断言结果
    }
  }
}