According to the docs, stat should include constants S_IFDOOR, S_IFPORT, S_IFWHT as well as the related S_IS... functions. However, these are only defined in _stat. I know that stat is a bit special (see bpo-11016), but that goes against PEP 399.

New changeset 7bb14316b8ceddb813f31040a299af94a57ab339 by Victor Stinner (Ronan Lamy) in branch 'master':
bpo-38109: Add missing constants to Lib/stat.py (GH-16665)
https://github.com/python/cpython/commit/7bb14316b8ceddb813f31040a299af94a57ab339

Ronan Lamy: Hum, do you really need this change to land in Python 3.7 and 3.8? If not, I will close PR 16690 and PR 16691 backports.

I don't think that it's worth it, since _stat should be always present in CPython.

Well, my interest in this is to reduce the divergence between PyPy and CPython, and, potentially, to help other implementations. So I actually care more about 3.7 than about 3.9, which I probably won't look at before 2021.

That said, I don't *need* anything: the fix is already in PyPy and we'll carry it forward regardless of what CPython does.

New changeset 8ab11c433a81b6c7ef84a66e36fbe199915e2ff6 by Victor Stinner (Miss Islington (bot)) in branch '3.8':
bpo-38109: Add missing constants to Lib/stat.py (GH-16665) (GH-16690)
https://github.com/python/cpython/commit/8ab11c433a81b6c7ef84a66e36fbe199915e2ff6

New changeset f5ed41c1ae9a575e965d55c6a5e86fb59181eee8 by Victor Stinner (Miss Islington (bot)) in branch '3.7':
bpo-38109: Add missing constants to Lib/stat.py (GH-16665) (GH-16691)
https://github.com/python/cpython/commit/f5ed41c1ae9a575e965d55c6a5e86fb59181eee8

I understand that backporting the change up to 3.7 makes your life easier, so I merged it. The change is safe and should not affect the regular use case (when the C extension _stat is used).

Thanks Ronan for this nice enhancement. It's good to see the stat module respect the PEP 399 ;-)

Thanks Victor!