view mercurial/utils/hashutil.py @ 45059:79f6f9fa18c1

documentation: add some internals documentation about bid merge

This is an important algorithm that was only documented on the wiki so far.

Some update to the algorithm (and associated doc) is to expected in the future
since the bid merge algorithm is bug-ridden when it comes to file deletion comes
to play.

Differential Revision: https://phab.mercurial-scm.org/D8711

from __future__ import absolute_import

import hashlib

try:
    from ..thirdparty import sha1dc

    sha1 = sha1dc.sha1
except (ImportError, AttributeError):
    sha1 = hashlib.sha1