C# – Rhino Mocks – Using Arg.Matches

cnetrhino-mocksunit testing

I have a function I am mocking which takes an argument object as a parameter. I want to return a result based on the values in the object. I cannot compare the objects as Equals is not overriden.

I have the following code:

_tourDal.Stub(x => x.GetById(Arg<TourGet>.Matches(y => y.TourId == 2), null)).Return(
                new Tour() 
                {
                    TourId = 2,
                    DepartureLocation = new IataInfo() { IataId = 2 },
                    ArrivalLocation = new IataInfo() { IataId = 3 }
                });

This should return the object specified when the supplied parameter has a TourId of 2.

This looks like it should work, but when I run it, I get the following exception:

When using Arg, all arguments must be defined using Arg.Is,
Arg.Text, Arg.List, Arg.Ref or Arg.Out. 2 arguments
expected, 1 have been defined.

Any ideas what I need to do to resolve this?

Best Answer

You need to use the same syntax for your second null argument, something along these lines (I haven't tested it):

_tourDal.Stub(x => x.GetById(Arg<TourGet>.Matches(y => y.TourId == 2), Arg<TypeName>.Is.Null)).Return(
            new Tour() 
            {
                TourId = 2,
                DepartureLocation = new IataInfo() { IataId = 2 },
                ArrivalLocation = new IataInfo() { IataId = 3 }
            });

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C# – Should ‘using’ directives be inside or outside the namespace

There is actually a (subtle) difference between the two. Imagine you have the following code in File1.cs:

// File1.cs
using System;
namespace Outer.Inner
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Now imagine that someone adds another file (File2.cs) to the project that looks like this:

// File2.cs
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}

The compiler searches Outer before looking at those using directives outside the namespace, so it finds Outer.Math instead of System.Math. Unfortunately (or perhaps fortunately?), Outer.Math has no PI member, so File1 is now broken.

This changes if you put the using inside your namespace declaration, as follows:

// File1b.cs
namespace Outer.Inner
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    class Foo
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        {
            double d = Math.PI;
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}

Now the compiler searches System before searching Outer, finds System.Math, and all is well.

Some would argue that Math might be a bad name for a user-defined class, since there's already one in System; the point here is just that there is a difference, and it affects the maintainability of your code.

It's also interesting to note what happens if Foo is in namespace Outer, rather than Outer.Inner. In that case, adding Outer.Math in File2 breaks File1 regardless of where the using goes. This implies that the compiler searches the innermost enclosing namespace before it looks at any using directive.

What are the differences between mocks and stubs on Rhino Mocks

As per this

... Put simply there is a difference between Mock and Stub objects and RhinoMocks recognizes that allowing us to write tests that better state their purpose.

Mock objects are used to define expectations i.e: In this scenario I expect method A() to be called with such and such parameters. Mocks record and verify such expectations.

Stubs, on the other hand have a different purpose: they do not record or verify expectations, but rather allow us to “replace” the behavior, state of the “fake”object in order to utilize a test scenario ...

Best Answer

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C# – Should ‘using’ directives be inside or outside the namespace

What are the differences between mocks and stubs on Rhino Mocks

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