Blog by Sumana Harihareswara, Changeset founder

23 Nov 2013, 10:40 a.m.

How Comprehensive Are Your Unit Tests? Coverage.py Knows

Hi, reader. I wrote this in 2013 and it's now more than five years old. So it may be very out of date; the world, and I, have changed a lot since I wrote it! I'm keeping this up for historical archive purposes, but the me of today may 100% disagree with what I said then. I rarely edit posts after publishing them, but if I do, I usually leave a note in italics to mark the edit and the reason. If this post is particularly offensive or breaches someone's privacy, please contact me.

I've been writing and maintaining unit tests for my project. But only on Thursday did a colleague's presentation remind me that I could run a code coverage tool to check which code paths my tests are or aren't exercising.

I found it super easy to install and run coverage.py, and it only took marginally more fuss to --omit="~/.virtualenvs/*". The detailed feedback helped me increase my coverage from 70% to 82%; yay! Thanks, Ned Batchelder & other coverage.py contributors.