HowTo :CPPUNIT to unittest MFC/UI application

[Venkataramani Krishnamurthy]

Hi There
Has anyone tried using CPPUNIT unit test tool for an MFC application? My application is MFC based and it has property sheets, property pages and dialogs. How do I use CPPUNIT for unit testing this MFC application. I understand the tool's usage for normal C++ classes like ComplexNumber, BoardGame, etc. But I would like to know how to use it with my MFC application. MFC application is also C++ based but they differ in that it involves UI components. Also, there are lots of inter dependencies between the objects. If someone can provide an example that would be excellent.

I appreciate any feedback on this.

Thank you very much,
Ramani

PS - Sorry for the duplication. I already posted this in the Help forum. I wanted to post it here too to catch everyone's attention and any possible help.

[Pierre Boudreau]

Your questions is not specific to CPPUnit.  It is a general problem with unit testing.  User interfaces are difficult to unit test.  The best solution I know is to design your application with testability in mind.  Some patterns like Model View Controler [GoF] enhance testability by enabling you to stub out the view class and test the other ones.  See http://www.c2.com/cgi/wiki?TestFirstUserInterfaces for several other tips on writing user interfaces test first.

For interdependencies, you would probably find Michael Feathers' work usefull.  See http://groups.yahoo.com/group/welc/files/ for a draft of a book he is writing for working effectively with legacy code.  My advice:  MAKE YOUR CLASSES INDEPENDANT AND MAKE YOUR UI CLASSES AS THIN AS POSSIBLE.  It will save you a lot of trouble when maintaing and enhancing your application in the future.

[Wolfgang Stoecher]

If you can separate the code you want to test from the GUI (I do not write unit tests for GUI-code; if your GUI-specific code is thin as suggested above, then there should be plenty of code for testing left) then you might try the following approach with three projects in one workspace:
- the core code (lib or dll)
- the application (an exe using the above lib or dll)
- the unit tests (using the above lib or dll)
With the compilation dependencies properly set, the separation into three projects will not harm your efficiency.

Wolfgang