[Herring]

Agreed, but with one exception: are tests supposed to cover all observable behavior? Usually people are happy with just eliminating large/easy classes of bad (unintended) behavior, otherwise they go for formal verification which is an entirely different ballgame.

[sarchertech]

No they aren’t because they can’t (at least not without becoming so complicated that there’s no longer a point).

But humans are much better at reasoning about whether a change is going to impact observable behavior than current LLMs are as evidenced by the fact that LLMs require a test suite or something similar to build a working app longer than a few thousand lines.