At some point you have to decide which parts of your programm you want to cover with unit-tests.
If you're developing test-first then you're off the hook as you already have your test cases. Congratulations. If you're not so lucky (that's the case in our project) you have to decide for which parts of your programm you are going to write unit-tests.
Is there a good and methodic approach to decide what to cover with unitt-tests? Ecspecially one that is more specific than asking yourself what should I test here?
?