Visual Studio Unit Testing of Windows Forms

Question

We're working on a project here in Visual Studio 2008. We're using the built-in testing suite provided with it (the Microsoft.VisualStudio.TestTools.UnitTesting namespace). It turns out, that much to our chagrin, a great deal of complexity (and therefore errors) have wound up coded into our UI layer. While our unit tests do a decent job of covering our business layer, our UI layer is a constant source of irritation. We'd ideally like to unit-test that, as well. Does anyone know of a good "Microsoft-compatible" way of doing that in visual studio? Will it introduce some sort of conflict to 'mix' unit testing frameworks like nUnitForms with the Microsoft stuff? Are there any obvious bear traps I should be aware of with unit-testing forms?

Answer 1

You would need to refactor the UI so that UI does not need any unit testing. UI should contain minimum or no business logic. There are many patterns that deal with this issue. Martin Fowler has a very good article that explains a lot about these patterns: http://martinfowler.com/eaaDev/uiArchs.html

There is a small chapter in the Refactoring book by Martin Fowler that talks about refactoring the non testable UI. You could also read Working Effectively With Legacy Code.

Note: There are tool that could be used to automate the UI testing. SilkTest comes to my mind. But I would not use them if possible.