How to mock/isolate internal classes in VS 2012 with Fakes Framework shims?

Question

So, the issue is that I have a bunch of internal classes in my assembly that are used by the class I want to test. Since accessors have been removed from VS2012, I'm fine with using [InternalsVisibleTo] and that works great... except when I try to shimify my internal classes, they are not visible to the Fakes framework. I should also note that the particular class I am dealing with is a static class with static methods, and I don't really want to refactor everything to use interfaces (and using stubs) because of resistance in the organization to that level of refactoring.

Is there a way to make these internal members usable by the shims context in Visual Studio 2012 without resorting to interfacing (literally) everything?

Answer 1

The following page describes how to make internal types visible to the generated fakes assembly. http://msdn.microsoft.com/en-us/library/hh708916.aspx#bkmk_internal_types

Which says:

The Fakes code generator will generate shim types and stub types for types that are visible to the generated Fakes assembly. To make internal types of a shimmed assembly visible to Fakes and your test assembly, add InternalsVisibleToAttribute attributes to the shimmed assembly code that gives visibility to the generated Fakes assembly and to the test assembly.

[assembly: InternalsVisibleTo("FileSystem.Fakes")]
[assembly: InternalsVisibleTo("FileSystem.Tests")]

You also need an InternalsVisibleToAttribute to allow your test assembly access the internal types from the target assembly. In other words, you need:

[assembly: InternalsVisibleTo("TargetAssembly.Fakes")]
[assembly: InternalsVisibleTo("TestAssembly")]