contrib/python-hook-examples.py

py3: write out hgextindex as bytes in setup.py

I hit this trying to build the py2exe target using python3, just to see what
would happen.  After commenting out `py2exe.Distribution` in setup.py and
pointing to a local copy of py2exe that supports python3[1], it complained that
`out` was bytes, not str.

[1] https://github.com/albertosottile/py2exe/releases/tag/v0.9.3.0

'''
Examples of useful python hooks for Mercurial.
'''
from __future__ import absolute_import
from mercurial import (
    patch,
    util,
)

def diffstat(ui, repo, **kwargs):
    '''Example usage:

    [hooks]
    commit.diffstat = python:/path/to/this/file.py:diffstat
    changegroup.diffstat = python:/path/to/this/file.py:diffstat
    '''
    if kwargs.get('parent2'):
        return
    node = kwargs['node']
    first = repo[node].p1().node()
    if 'url' in kwargs:
        last = repo.changelog.tip()
    else:
        last = node
    diff = patch.diff(repo, first, last)
    ui.write(patch.diffstat(util.iterlines(diff)))