As detailed in the commit message, this change makes the egg_info command
write out setup requirements as well as install requirements. The motivation for this
change is to allow a tool I'm writing for the Baserock project to easily obtain "build"
dependencies from a python package.
The change itself is quite minimal and is hopefully of some benefit to others.
Fine by me - PEP 426 and any associated updates to the sdist and wheel format definitions are deliberately designed to co-exist with the existing setuptools metadata files, and that will cover this one as well.
Likely worth mentioning on distutils-sig though - PEP 426 standardisation is still some time away, and this may be useful to other folks in the meantime.
It would also be handy if there was a setuptools docs update associated with the change :)