I've read much here and there about tests, but due to my typical programming tasks I've never really needed to write any, with some minor exceptions. Now I have some codebase that has served me right for quite a lot of time, but I {want,need} to

The point is that I want to start from the current implementation of the thingie, which in turn must be a sort of reference one, as a starting point: thus I want to write tests for any improved one, that will make sure it will behave like the former in "all" commonly covered cases. I see two possible strategies:

The first approach is obvious, and with the second I mean something like moving code to a "private" (e.g. with a particular naming scheme) module and write tests like:

ok( func eq _Reference::func, 'func');

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I see pros and cons in both ways. Any idea?!?

In reply to Recommendations re tests wrt a reference implementation by blazar

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