如何在不重置整个存根的情况下重置存根中属性的结果?

我不懂犀牛戏法,所以我可能完全错过了一些东西。

假设我有一个接口,它有六个属性:

public interface IFoo {
  string Foo1 { get; } // Required non-null or empty
  string Foo2 { get; } // Required non-null or empty
  string Foo3 { get; }
  string Foo4 { get; }
  int Foo5 { get; }
  int Foo6 { get; }
}

以及一个实现,该实现采用类似的对象,但没有相同的约束,并创建一个ifoo实例:

public interface IFooLikeObject {
  string FooLikeObject1 { get; } // Okay non-null or empty
  string FooLikeObject2 { get; } // Okay non-null or empty
  string FooLikeObject3 { get; }
  string FooLikeObject4 { get; }
  string FooLikeObject5 { get; } // String here instead of int
  string FooLikeObject6 { get; } // String here instead of int
}

public class Foo : IFoo {
  public Foo(IFooLikeObject fooLikeObject) {

    if (string.IsNullOrEmpty(fooLikeObject.Foo1)) {
      throw new ArgumentException("fooLikeObject.Foo1 is a required element and must not be null.")
    }

    if (string.IsNullOrEmpty(Foo2)) {
      throw new ArgumentException("fooLikeObject.Foo2 is a required element and must not be null")
    }

    // Make all the assignments, including conversions from string to int...

  }
}

现在,在我的测试中,我想测试在适当的时间抛出异常,以及在从字符串到int的转换失败时抛出的异常。

因此,我需要截取ifoolikeObject,以返回当前未测试的值的有效值,因为我不想在每个测试方法中重复此代码,所以将其提取到单独的方法中。

public IFooLikeObject CreateBasicIFooLikeObjectStub(MockRepository mocks) {
  IFooLikeObject stub = mocks.Stub<IFooLikeObject>();

  // These values are required to be non-null
  SetupResult.For(stub.FooLikeObject1).Return("AValidString");
  SetupResult.For(stub.FooLikeObject2).Return("AValidString2");
  SetupResult.For(stub.FooLikeObject5).Return("1");
  SetupResult.For(stub.FooLikeObject6).Return("1");
}

这对于测试foo3和foo4来说已经足够好了,但是当测试foo1、2、5或6时,我得到:

System.InvalidOperationException : The result for IFooLikeObject.get_FooLikeObject1(); has already been setup. Properties are already stubbed with PropertyBehavior by default, no action is required

例如:

[Test]
void Constructor_FooLikeObject1IsNull_Exception() {
  MocksRepository mocks = new MocksRepository();
  IFooLikeObject fooLikeObjectStub = CreateBasicIFooLikeObjectStub(mocks);

// This line causes the exception since FooLikeObject1 has already been set in CreateBasicIFooLikeObjectStub()
  SetupResult.For(fooLikeObjectStub.FooLikeObject1).Return(null); 

  mocks.ReplayAll();

  Assert.Throws<ArgumentException>(delegate { new Foo(fooLikeObjectStub); });
}

如何设置它,以便我可以重写已经设置了返回值的单个属性,而不必重新执行所有其他属性?