How much testing is too much?

You know how painful it is to work with badly tested code. Every time you fix a bug, you create five more. And when things do work, you never really know if it was designed that way, or just worked coincidentally.

On the other hand, you just wrote what seems like 200 tests to ship one tiny feature. You constantly have to redesign already-working code to hit 100% test coverage. You can’t shake the feeling that your best-tested code is somehow getting less readable. And worst of all, you’re sta...