Things I got wrong about unit tests

I ran into this again last week, so here is a short note for future me. Measuring before changing anything saved me from a pointless rewrite. The documentation was correct, I just did not read it carefully.

Naming things clearly helped more than any clever trick. The fix turned out to be one line, after an hour of looking in the wrong place. It is worth writing down the commands you only need twice a year.

Next time I will start with the boring solution and see if it is enough. Writing a tiny test first made the problem obvious. Plain text keeps winning for small personal projects. Most of the time the simplest tool is good enough.