模拟SQL输出参数

Question

我模拟了数据访问层的几种方法,但在某些方法中,设置了SQL输出参数的值.我怎么嘲笑这个？

方法:

var wrappedParameters = new SqlParameter[3];
            wrappedParameters[0] = new SqlParameter("@username",username);
            wrappedParameters[1] = new SqlParameter("@password",password);
            wrappedParameters[2] = new SqlParameter("returnValue",SqlDbType.Int) { Direction =ParameterDirection.ReturnValue };

            dal.ExecuteUsingStoredProcedure("GetUser", wrappedParameters);

模拟(我尝试使用"OutRef",但这不起作用):

using (mocks.Record())
        {
            Expect.Call(dal.ExecuteUsingStoredProcedure("",> null)).Return(true).IgnoreArguments().OutRef(1);
        }

但那没有用.当我执行SP GetUser时,设置了param返回值,但我不知道如何模拟它

Answer 1

我认为你处理这个问题的方式是错误的。您的 DAL 界面应如下所示：

/// <summary>
/// Models a service which holds the user information.
/// </summary>
public interface IUserRepository
{
   /// <summary>
   /// Gets the user with the given name, or <c>null</c> if no user with
   /// that name and password exists.
   /// </summary>
   /// <exception cref="IOException">
   /// An I/O problem occurred while accessing the repository.
   /// </exception>
   User TryGetUser(string name, string password);
}

DAL 抽象现在隐藏了使用存储过程的事实。事实上，DAL 甚至可能不是数据库：它可以是磁盘上的文本文件、Web 服务、模拟或其他任何东西。

现在，为了测试使用 DAL 的代码而模拟 DAL 变得微不足道。在这些示例中，我选择了登录屏幕的视图模型（也称为演示模型）作为测试系统：

[Test]
public void Login_sets_user_and_goes_to_main_screen_when_TryGetUser_not_null()
{
    var userRepositoryStub = MockRepository.GenerateStub<IUserRepository>();
    var user = new User(...);
    userRepositoryStub.Stub(x=>x.GetUserByName("foo","bar")).Return(user);
    var sessionStub = MockRepository.GenerateStub<ISession>();
    var loginScreenViewModel = 
        new LoginScreenViewModel(sessionStub, userRepositoryStub);

    loginScreenViewModel.UserName = "foo";
    loginScreenViewModel.Password = "bar";
    loginScreenViewModel.Login();

    userRepositoryStub.AssertWasCalled(x=>x.TryGetUser("foo","bar"));
    sessionStub.AssertWasCalled(x=>x.ShowMainScreen());
    Assert.AreEqual(user, session.User);
}

。

[Test]
public void Login_shows_error_when_TryGetUser_returns_null()
{
    var userRepositoryStub = MockRepository.GenerateStub<IUserRepository>();
    var sessionStub = MockRepository.GenerateStub<ISession>();
    var loginScreenViewModel = 
        new LoginScreenViewModel(sessionStub, userRepositoryStub);

    loginScreenViewModel.UserName = "foo";
    loginScreenViewModel.Password = "bar";
    loginScreenViewModel.Login();

    Assert.AreEqual(loginScreenViewModel.Error, 
        "User 'foo' does not exist or password is incorrect"));
    userRepositoryStub.AssertWasCalled(x=>x.TryGetUser("foo","bar"));
    sessionStub.AssertWasNotCalled(x=>x.ShowMainScreen());
    Assert.IsNull(session.User);
}