git-mig-auto-msg

#!/usr/bin/env python3
"""
Usage:

    # basic usage
    git mig-auto-msg "some changes" | git commit -F-

    # if you specify coauthors, you need to preserve the verbatim generated message to avoid
    # removing double empty lines (needed to be correctly parsed by github)
    git mig-auto-msg -c nse "odoo.com specific" | git commit -F- --cleanup=verbatim

    # when amending commit, the `--amend` flag has to be used to determine all files touched by
    # then commit
    git mig-auto-msg --amend | git commit -F- --amend

"""

from collections import defaultdict
from email.utils import parseaddr, formataddr
from functools import reduce
import operator
from subprocess import check_output

import click

remote = check_output(['git', 'remote', 'get-url', 'origin']).decode().strip()
assert remote in {"git@github.com:odoo/upgrade.git", "git@github.com:odoo/saas-migration.git"}

def rs(s):
    assert s
    if len(s) == 1:
        return list(s)[0]
    return '{' + ','.join(sorted(s)) + '}'

def format_coauthor(coauthor):
    p = parseaddr(coauthor)
    if p[0]:
        return formataddr(p)
    # no formated correctly, search author
    commit = check_output(["git", "rev-list", "--all", "-i", "-n1", "--author", coauthor]).decode().strip()
    if not commit:
        return coauthor
    author = check_output(["git", "show", "--no-patch", "--format=%an%n%ae", commit]).decode().strip()
    return formataddr(author.split("\n"))


@click.command()
@click.option('-A', 'tag', flag_value='[ADD]')
@click.option('-F', 'tag', flag_value='[FIX]')
@click.option('-c', 'coauthors', type=str, multiple=True)
@click.option('--amend', is_flag=True)
@click.argument('message', required=False)
def main(tag=None, message=None, coauthors=(), amend=False):
    status = check_output(['git', 'status', '--porcelain']).decode()
    if amend:
        status += "\n"
        status += check_output(['git', 'show', '--format=', '--name-status', 'HEAD']).decode()

    mods = defaultdict(set)

    util = False
    guess_tag = '[ADD]'

    for l in status.splitlines():
        if not l or l[0] not in 'AM':
            continue
        if l[0] == 'M':
            guess_tag = '[FIX]'
        f = l[2:].strip()

        if f.startswith("migrations/util/"):
            util = True
            continue

        try:
            _, module, version, *_ = f.split('/')
        except ValueError:
            # Not an upgrade script?
            continue
        version = '.'.join(version.split('.')[:2]) if version != '0.0.0' else '0.0.0'
        mods[module].add(version)

    agg = []
    if util:
        agg = ['util']

    while mods:
        common_versions = reduce(operator.and_, mods.values())
        agg_mod = {k for k, v in mods.items() if v == common_versions}
        if not agg_mod:
            break
        agg.append('{}/{}'.format(rs(agg_mod), rs(common_versions)))
        new_mods = defaultdict(set)
        for m in mods:
            v = mods[m] - common_versions
            if v:
                new_mods[m] = v
        mods = new_mods

    for m, v in mods.items():
        agg.append('{}/{}'.format(m, rs(v)))

    if tag is None:
        tag = guess_tag
    output = '{} {}'.format(tag, ','.join(agg))
    if message:
        output += ': ' + message

    if coauthors:
        output += "\n\n\n" + "\n".join("Co-authored-by: %s" % format_coauthor(ca) for ca in coauthors)

    print(output)


if __name__ == '__main__':
    main()