Apparently, if I edit partest-extras source in the main repo, the jar is only rebuilt on a clean build. (I hope it's rebuilt; it's still building.) I'll volunteer to look at this niche use case. My antabilities are ancient now, like pre-ant-1.6. This is like one of those apocalyptic sci-fi movies where you wake up from stasis, only to find the world in ruins but your little valet robot still beeping along at your side, ready to dress your clothes horse, albeit in fashions three hundred years out of date.

Or, maybe just a dependency on partest.task is missing.