This is an existing C# .NET WinForms project. I assume it was not developed with unit tests in mind from the very beginning. It uses a Model-View-Controller architecture, and the backend is a content repository (a kind of heirarchical database) which I am not too familiar with, since I have only touched the front end.
I have been asked to create interfaces for each
public class, including the forms. These will be used for unit testing with NUnit. This is complete. What is the best approach now? The only thing that comes to mind at the moment, is to create concrete classes from these interfaces, which is just re-implementing the existing classes in the application. Outside of the fact that this will make the unit tests "mind their own business", I don't see what the purpose of re-writing the classes is.
If this is the correct approach, it does not seem difficult to test things such as the Model, which contains an OOP representation of the database. How should the forms be tested?