Blog » So there's a thing we use at work which I call a ratchet.
In our codebase, there are "patterns" which we used to use all the time, but we decided to stop using them, but removing all of the existing instances at once is too much work. We want to remove all of these instances eventually, and in the meantime we want to make absolutely sure that they don't proliferate via copy-and-paste. So what we have is a ratchet, a script which runs at source code linting time and counts all of these "pattern" instances across the codebase. If the script counts too many instances, it raises an error, explaining why we don't want more of that "pattern". If it counts too few, it also raises an error, this time congratulating you and prompting you to lower the expected number.
This script is intentionally extremely simple. The expected numbers are hard-coded in the script itself. The "patterns" for which it scans our code are not advanced, abstract Gang of Four-style software design patterns but plain ...