At work I recently set up a Jenkins instance to run all our tests whenever someone pushes changes to the master branch of our git repo. And, after changing some stuff in our code that made the perl debugger cry*, I added Devel::Cover to the mix. So now, Jenkins not only notifies us by email whenever someone is naughty and makes the tests fail, it also generates a lovely report of how much of our code is actually tested.

Naturally, the first thing I looked at was how well-covered our test…