On Wed, May 31, 2017, at 04:31 PM, Donald Stufft wrote:
The hook is also so a tool like tox or TravisCI or twine can produce a sdist that can be uploaded to PyPI or similar.
This seems like a distinct operation from 'prepare the files needed to build a wheel', although they are related. For instance, sdists typically contain docs (in source form), but you don't need these to build a wheel. It would be fairly easy for Flit to identify the files needed to build a wheel, but it can only identify the files needed for an sdist with the help of a VCS.
Would you be happy with a compromise where PEP 517 defines a (possibly optional) hook like 'prepare_build_files', and we leave a standardised interface for preparing an sdist to be hashed out in a later PR?