犀牛模拟异常：预期 #1，实际 #2。

Question

我有两个测试。第一个测试正常工作。第二个测试看起来和第一个测试一样。然而，当我运行第二个测试时，我会收到异常。

第一个测试：

public void GetCurrentBalance_Should_getting_rigth_balanse()
{
    // Arrange
    double balance = 10;

    var mocks = new MockRepository();
    IUnitOfWork unitOfWork = mocks.Stub<IUnitOfWork>();
    unitOfWork.Stub(svc => svc.AccountRepository.Get()).Return(new List<Account> {new Account { Balance = balance }}); 

    AccountService accountService = new AccountService(unitOfWork); 

    // Act
    mocks.ReplayAll();
    var result = accountService.GetCurrentBalance();

    //Assert
    Assert.AreEqual(balance, result);
}

第二个测试：

public void WithdrawMoney_Balance_should_decrease_when_money_been_withdrawn()
{
    // Arrange
    double balance = 10;

    var mocks = new MockRepository();
    IUnitOfWork unitOfWork = mocks.Stub<IUnitOfWork>();
    unitOfWork.Stub(svc => svc.AccountRepository.Get()).Return(new List<Account> { new Account { Balance = balance } });

    AccountService accountService = new AccountService(unitOfWork);

    // Act
    mocks.ReplayAll();
    var result = accountService.WithdrawMoney(1); // this line is different

    //Assert
    Assert.AreEqual(balance - 1, result);
}

我的服务范围包括：

public class AccountService : BaseService, IAccountService
{
    public AccountService(IUnitOfWork unitOfWork)
        : base(unitOfWork)
    {
    }

    public double WithdrawMoney(double amountOfMoney)
    {
        var currentBalance = GetCurrentBalance();

        if (currentBalance < amountOfMoney)
        {
            throw new BusinessLayerException("error!");
        }

        var lastAccount = GetLastAccount();

        if (lastAccount == null)
        {
            throw new BusinessLayerException("error!");
        }

        lastAccount.Balance -= amountOfMoney;

        unitOfWork.AccountRepository.Update(lastAccount);
        unitOfWork.Save();

        return lastAccount.Balance;
    }

    public double GetCurrentBalance()
    {
        var lastAccount = GetLastAccount();

        if (lastAccount == null)
        {
            return 0;
        }

        return lastAccount.Balance;
    }

    private Account GetLastAccount()
    {
        var lastAccount = unitOfWork.AccountRepository.Get().FirstOrDefault();

        return lastAccount;
    }
}

我得到了以下的调用堆栈：

Rhino.Mocks.Exceptions.ExpectationViolationException : IUnitOfWork.get_AccountRepository(); Expected #1, Actual #2.
   at Rhino.Mocks.MethodRecorders.UnorderedMethodRecorder.DoGetRecordedExpectation(IInvocation invocation, Object proxy, MethodInfo method, Object[] args)
   at Rhino.Mocks.MethodRecorders.MethodRecorderBase.GetRecordedExpectation(IInvocation invocation, Object proxy, MethodInfo method, Object[] args)
   at Rhino.Mocks.Impl.ReplayMockState.DoMethodCall(IInvocation invocation, MethodInfo method, Object[] args)
   at Rhino.Mocks.Impl.ReplayMockState.MethodCall(IInvocation invocation, MethodInfo method, Object[] args)
   at Rhino.Mocks.MockRepository.MethodCall(IInvocation invocation, Object proxy, MethodInfo method, Object[] args)
   at Rhino.Mocks.Impl.Invocation.Actions.RegularInvocation.PerformAgainst(IInvocation invocation)
   at Rhino.Mocks.Impl.RhinoInterceptor.Intercept(IInvocation invocation)
   at Castle.DynamicProxy.AbstractInvocation.Proceed()
   at Castle.Proxies.IUnitOfWorkProxy2936ffa6dea844258ad88f7a7e99dbc0.IUnitOfWork.get_AccountRepository()
   at Service.AccountService.GetLastAccount() in AccountService.cs: line 90
   at Service.AccountService.WithdrawMoney(Double amountOfMoney) in AccountService.cs: line 61
   at ServiceTest.AccountServiceTest.WithdrawMoney_Balance_should_decrease_when_money_been_withdrawn() in AccountServiceTest.cs: line 48

- Denis

Answer 1

遵循以下规则进行 Rhione 模拟测试：

要使用 Rhino Mocks，只需按照以下步骤与模拟对象一起操作：

1. 创建模拟对象：mockrepository.CreateMock();

2. 记录您的期望：在 Record 块中。

3. 调用 ReplayAll 来告诉 Rhino Mocks 您已完成记录

4. 最重要的一步：在此处调用预期方法，例如：mockMyRhinoImplementation.HelloRhinoMocks（“ABC”）

注意：必须传递与记录的相同参数，否则它会再次抛出 ExpectationViolationException。

5. 调用 VerifyAll();

因此，两个测试之间的区别是一个带有参数，另一个没有... 尝试像下面这样使用

double number = 1;
var result = accountService.WithdrawMoney(number);

- Neel

Answer 2

我通过更改第二个测试解决了我的问题。我更改了一行： 从：

IUnitOfWork unitOfWork = mocks.Stub<IUnitOfWork>();

to:

IUnitOfWork unitOfWork = mocks.DynamicMock<IUnitOfWork>();

但我认为这是解决我的问题的不好的方法。

- Denis