Thats a calltip, not autocompletion. Calltips require searching backward from the `(` to find a name to lookup, and thats one of the places I alluded to where only looking for C names is hard coded see the NULL at the end [here](https://github.com/geany/geany/blob/d2740f21feb84b6f951398c6f683674b2b56bfed...)