mongodb - 无法实例化代理...找不到无参数构造函数

Question

我正在尝试使用 Moq 创建一个单元测试来测试 MongoDB.AspNet.Identity V2提供者。这句话让我很伤心:

var appUser = new Mock<PreRegistrationMVC.Models.ApplicationUser>();
var userStore = new Mock<MongoDB.AspNet.Identity.UserStore<PreRegistrationMVC.Models.ApplicationUser>>();

似乎 userStore 无法正确实例化，这是错误。

Castle.DynamicProxy.InvalidProxyConstructorArgumentsException was unhandled by user code
  HResult=-2147024809
  Message=Can not instantiate proxy of class: MongoDB.AspNet.Identity.UserStore`1[[MVC.Models.ApplicationUser, MVC, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].
Could not find a parameterless constructor.
  Source=Moq
  StackTrace:
       at Castle.DynamicProxy.ProxyGenerator.CreateClassProxyInstance(Type proxyType, List`1 proxyArguments, Type classToProxy, Object[] constructorArguments)
       at Castle.DynamicProxy.ProxyGenerator.CreateClassProxy(Type classToProxy, Type[] additionalInterfacesToProxy, ProxyGenerationOptions options, Object[] constructorArguments, IInterceptor[] interceptors)
       at Moq.Proxy.CastleProxyFactory.CreateProxy(Type mockType, ICallInterceptor interceptor, Type[] interfaces, Object[] arguments)
       at Moq.Mock`1.<InitializeInstance>b__2()
       at Moq.PexProtector.Invoke(Action action)
       at Moq.Mock`1.InitializeInstance()
       at Moq.Mock`1.OnGetObject()
       at Moq.Mock.GetObject()
       at Moq.Mock.get_Object()
       at Moq.Mock`1.get_Object()
       at MVC_Tests.Identity.Accounts.AccountController_Test.TestSuccessfulRegister() in c:\Users\Tim\Documents\Visual Studio 2013\Projects\PreRegistrationApp\MVC_Tests\Identity\Accounts\AccountController_Test.cs:line 108
  InnerException: 

我对 Moq 完全陌生，所以我正在寻找: Moq 需要什么类型的设置来实例化它？ UserStore 类是否存在与 Moq 不兼容的问题？

感谢阅读。

Answer 1

MOQ 适用于模拟接口(interface)，但不适用于具体类。所以不要模拟具体的类，而是要求接口(interface):

var userStore = new Mock<IUserStore<PreRegistrationMVC.Models.ApplicationUser>>();

另外 ApplicationUser 应该是 POCO，所以不需要模拟它，只需创建它的实例，没有 MOQ 并在测试中使用。