4

我是测试驱动开发的新手，并尝试对 mvc 应用程序进行单元测试。我正在使用 Moq 和 Ninject，并尝试遵循工作单元存储库模式。我的所有测试都收到 System.ArgumentException 错误。这是错误消息和错误堆栈跟踪：

Test method LOMSv4.Tests.Controllers.AutobytelControllerTest.Index_Contains_All_Requests threw exception: 
System.ArgumentException: Can not instantiate proxy of class: LOMSv4_DAL.Autobytel.Concrete.RequestRepository.
Could not find a parameterless constructor.

参数名称：constructorArguments

Castle.DynamicProxy.ProxyGenerator.CreateClassProxyInstance(Type proxyType, List`1 proxyArguments, Type classToProxy, Object[] constructorArguments)
Castle.DynamicProxy.ProxyGenerator.CreateClassProxy(Type classToProxy, Type[] additionalInterfacesToProxy, ProxyGenerationOptions options, Object[] constructorArguments, IInterceptor[] interceptors)
Moq.Proxy.CastleProxyFactory.CreateProxy[T](ICallInterceptor interceptor, Type[] interfaces, Object[] arguments)
Moq.Mock`1.<InitializeInstance>b__0()
Moq.PexProtector.Invoke(Action action)
Moq.Mock`1.InitializeInstance()
Moq.Mock`1.OnGetObject()
Moq.Mock.GetObject()
Moq.Mock.get_Object()
Moq.MockDefaultValueProvider.ProvideDefault(MethodInfo member)
Moq.QueryableMockExtensions.FluentMock[T,TResult](Mock`1 mock, Expression`1 setup)
lambda_method(Closure )
Moq.Mock.GetInterceptor(Expression fluentExpression, Mock mock)
Moq.Mock.<>c__DisplayClass1c`2.<Setup>b__1b()
Moq.PexProtector.Invoke[T](Func`1 function)
Moq.Mock.Setup[T,TResult](Mock mock, Expression`1 expression, Func`1 condition)
Moq.Mock`1.Setup[TResult](Expression`1 expression)

这是我的测试课： 

[TestClass]
public class AutobytelControllerTest
{
    Mock<IUnitOfWork> mock = new Mock<IUnitOfWork>();

    [TestMethod]
    public void Index_Contains_All_Requests()
    {
        //Arrange
        AutobytelController controller = new AutobytelController(mock.Object);
        mock.Setup(m => m.RequestRepository.SelectAll()).Returns(new abtRequest[] {
            new abtRequest {RequestID = 1, Title = "Request 1", Description = "Request Description1", UserName = "NewUser", RequestStatus = 0},
            new abtRequest {RequestID = 2, Title = "Request 2", Description = "Request Description2", UserName = "ReturnUser", RequestStatus = 1}
        }.AsQueryable());

        //Act
        abtRequest[] result = ((AutobytelHomeViewModel)controller.Index().Model).Requests.ToArray();
        //Assert
        Assert.AreEqual(result.Length, 2);
        Assert.AreEqual("Request 1", result[0].Title);
        Assert.AreEqual("Request 2", result[1].Title);
    }

我有一个 IUnitofWork 接口和类、通用存储库接口和类以及一个实现通用存储库的请求存储库

public interface IUnitOfWork
{
    RequestRepository RequestRepository { get; }
    void Save();
}

public class UnitOfWorkRepository : IUnitOfWork, IDisposable
{
    private AutobytelEntities context = new AutobytelEntities();
    private RequestRepository requestRepository;

    public RequestRepository RequestRepository
    {
        get
        {
            if (this.requestRepository == null)
            {
                //this.requestRepository = new GenericRepository<abtRequest>(context);
                this.requestRepository = new RequestRepository(context);
            }
            return requestRepository;
        }
    }

    public void Save()
    {
        context.SaveChanges();
    }

    private bool disposed = false;

    protected virtual void Dispose(bool disposing)
    {
        if (!this.disposed)
        {
            if (disposing)
            {
                context.Dispose();
            }
        }
    }

    public void Dispose()
    {
        Dispose(true);
        GC.SuppressFinalize(this);
    }
}

public class GenericRepository<TEntity> : IGenericRepository<TEntity> where TEntity : class
{
    internal AutobytelEntities context;
    internal IObjectSet<TEntity> objectSet;


    public GenericRepository(AutobytelEntities context)
    {
        this.context = context;
        this.objectSet = context.CreateObjectSet<TEntity>();
    }

    public virtual IQueryable<TEntity> SelectAll()
    {
        return objectSet.AsQueryable();
    }

    public virtual TEntity Update(TEntity entity)
    {
        context.ObjectStateManager.ChangeObjectState(entity, System.Data.EntityState.Modified);
        return entity;
    }

    public virtual void Delete(TEntity entity)
    {
        objectSet.DeleteObject(entity);
    }
}

    public class RequestRepository : GenericRepository<abtRequest>, IGenericRepository<abtRequest>
{
    public RequestRepository(AutobytelEntities context) : base(context)
    { }

    public virtual abtRequest SelectByUserName(string username)
    {
        return context.abtRequests.FirstOrDefault(i => i.UserName == username && (i.RequestStatus == 0 || i.RequestStatus == 1));
    }

    public virtual abtRequest SelectByRequestID(int requestID)
    {
        return context.abtRequests.FirstOrDefault(i => i.RequestID == requestID);
    }

使用 Ninject 我将 IUnitofwork 绑定到 UnitOfWork 类。

如果我将无参数构造函数添加到我的请求存储库，我的错误将得到解决 - 但因为我不想创建新的对象上下文，我想从工作单元存储库传递我的上下文。

如何解决此错误？

4

2 回答 2

6

我通过向我的 RequestRepository 添加一个接口并在我的工作单元中创建该接口的一个实例来解决此错误。我的 IUnit of Work 更改为：

public interface IUnitOfWork
{
    IRequestRepository RequestRepository { get; }
    void Save();
}

在我的 UnitOfWork 存储库中更改为：

private IRequestRepository requestRepository;

public IRequestRepository RequestRepository
{
    get
    {
        if (this.requestRepository == null)
        {
            this.requestRepository = new RequestRepository(context);
        }
        return requestRepository;
    }
}
于 2012-08-24T15:48:51.380 回答
2

这只是伪代码，但我希望它能让您更接近解决方案。您应该能够按照以下方式设置模拟：

//Arrange
var mockRepository = new Mock<RequestRepository>("CONSTRUCTOR ARGUMENT");
mockRepository.Setup(mr => mr.SelectAll()).Returns(new abtRequest[] {
            new abtRequest {RequestID = 1, Title = "Request 1", Description = "Request Description1", UserName = "NewUser", RequestStatus = 0},
            new abtRequest {RequestID = 2, Title = "Request 2", Description = "Request Description2", UserName = "ReturnUser", RequestStatus = 1}
            }.AsQueryable());
mock.SetupGet(uow => uow.RequestRepository).Returns(mockRepository.Object);

AutobytelController controller = new AutobytelController(mock.Object);

上面的代码为您的构造函数参数（“CONSTRUCTOR ARGUMENT”）提供了一个占位符 - 只需在此处提供适用于您的测试场景的最简单的东西。

于 2012-08-20T16:33:38.750 回答