To my mind, it should contain whatever is customary so it matches the average person's expectation, but I don't have preferences myself.

I'll look into what similarly arranged Python projects that use the setuptools backend and have manifest files are doing with them.

One thing I've come to wonder about is why the problem ingitpython-developers/gitdb#25 happened for gitdb but not for smmap or GitPython (both of which haveMANIFEST.in and neither of which lists it in itself).

Although this isn't a complete (or really any) explanation, on closer inspection, it looks from the error message like this was due to C code ingitdb that was since moved togitdb-speedups. (This was also a long time ago, using Python 2.)

All the C-related stuff ingitdb'sMANIFEST.in could probably be removed at this point and, at the same time, I thinkMANIFEST.in could be removed from itself too. But I'm not in a rush to do that, because maybe even more could should be removed from it, or maybe the file could be eliminated altogether.

Relating to#1716 (comment), I think the question of what belongs inMANIFEST.in can (and may need to) be revisited when making the project definitions declarative. I don't think I'll feel a need to propose changes to it, in any of the three projects, before that, so I'm closing this. However, this isnot with the intention of preventing anyone else who is interested in making improvements sooner from doing so!