AFAIK you can't, and there's no indication that will change. You may be able to virtualize a whole macOS install, though that's pretty difficult even on Apple hardware (source: I tried several times, and didn't get it to work well)
I think many open-source efforts are heading in the wrong direction. Let Apple make sure our software runs on their hardware, and let FOSS make sure that Apple software runs on FOSS platforms. Not the other way around.