I tried to create a toolpath for drilling and realized there are some things broken in PathDrilling. Adding and removing the features to drill were completely commented out, so current behavior is that all holes of the Base feature bigger than the tool diameter are drilled. Based on commit comments, these issues are already known by sliptronic at least I guess?
Anyway, to get the path done I modified the PathDrilling so that I am able to remove objects from the list, otherwise it would be impossible to drill with two different tools, for example. Also, I enabled the "Find All" -button in the Task Panel so that it resets the object list to contain all holes in the base feature. Adding features felt like out of my skills, so I didn't touch that.
I dont know if that is useful to merge, testing of it is very limited and as there are still broken features, a bigger overhaul should be done. But if someone happens to need drilling feature right now, here is a commit I made:
https://github.com/pekkaroi/FreeCAD/com ... dd64f32a7d