If you’re the one implementing the functions (or even if you’re not), there are tools such as pgtap that can help you with testing. I’ve used pgtap successful o

If you’re the one implementing the functions (or even if you’re not), there are tools such as pgtap that can help you with testing. I’ve used pgtap successful on a number of projects. There’s also no reason you can’t test the behavior of functions through a driver in some other language, though you’re now one step removed. I’m not aware of any coverage tools, though it’s been a while since I’ve looked. https://pgtap.org/ https://pgtap.org/