We unit test code's correctness—so why not unit test performance as well?

Having thought about the problem a little, here's my suggestion for a first step: testing big-O scalability.

https://pythonspeed.com/articles/big-o-tests/

#python

Unit testing your code’s performance, part 1: Big-O scaling

Your software’s speed needs some form of testing; big-O scaling is a good starting point.

Python⇒Speed
I posted this on reddit and forgot that people have Feelings about "unit" testing, a term that is so vague as to be almost useless.