Testing private methods using RhinoMocks

Question

I work in TDD environment and basically I am facing with a dilemma which I think is very important in TDD environment. As a programmer, you want your methods to be as readable as possible. To achieve that, we tend to partition our methods in multiple private methods as well. While doing that all that code which was moved to the private function looses it's test ability.

Rhino test class cannot see all those private methods and I need to be able to run tests against those methods as well. I do not want them to be public because it does not make sense to keep them public.

Any ideas?

Answer 1

If I qoute a part of your question:

[...] we tend to partition our methods in multiple private methods [...]

This is wrong. If you follow a single responsibility principle and good OOP design, your methods would be much independent and simpler. If you feel like you want to extract a yet another private method to make your public one look shorter, give it a thought first. Maybe, you can refactor it in a separate class?

You do not test private methods, because you test public contracts and not the details of implementations. If you want to have something distantly similar to private methods testing, make them internal and set InternalsVisibleTo attribute.

Another method (pointed by R. Harvey) is to write a wrapper class that wraps you private methods into public ones. This approach has a benefit that you don't need to make your private methods internal. The downside is that for every private method you will have a wrapper public method. So the amount of methods may double.