Whichever direction you go in (full re-write or cleanup), you might want to build some test cases first. You can go for both system tests (prod your application with HTTP requests and compare the output against saved runs, for example) and unit tests (call into some of your components directly from test scripts).

Of course, its only worth putting unit tests in for interfaces which you want to keep. This is a good thing, because it forces you to think through the interfaces you want.

Once you have your test suite (I am assuming you don't want to significantly change the app behaviour). You can go ahead and clean up an item at a time - for example hunt down a particular global var.

Hmmm...probably worth getting all the code to run 'strict' and '-w' as a first step. If you are going to be removing and renaming variables the last thing you want to be doing is referring to the old variables in places and not knowing about it.

Yes the above is shamelessly stolen from 'Refactoring' - but it is a good idea nonetheless.

I'm not sure I'd have the discipline to do this in your situation, but hey - you asked for advise :-)

In reply to Re: Rewriting a large code base by jbert
in thread Rewriting a large code base by Ovid

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