contrib/upstream_diff.py

#!/usr/bin/env python3
# Copyright 2021 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Compare local cherry-picks with upstream SHA1s.

This script compares local and UPSTREAM change by pulling
each into a patch file and compares the two patch files using meld.

You may need to install meld to use this script:
chromeos: emerge dev-vcs/git
debian: sudo apt-get install meld

1) generate list of commit messages that need to be compared. e.g.:
    git log remotes/cros/chromeos-3.18.. > /tmp/git.log

2)  run:  upstream_diff.py /tmp/git.log

3) Close the meld window once you are finished inspecting to see the next one
"""

import re
import sys
from subprocess import call
commit_start = 0
patchid = 1
l_sha = ''

f = open(sys.argv[1], 'r')

for line in f.readlines():
    if l_sha != '':
        # first line with leading white space is description
        if l_descr != '':
            if re.match('^    .*$', line):
                l_descr = line.strip()

            if l_descr[0:8] != 'UPSTREAM:':
                print('----------------------')
                print('Skipping !UPSTREAM ' + l_sha[0:9] + ' ' + l_descr)
                l_sha = ''
                l_descr = ''
                continue

        if re.match(r'^    \(cherry picked from commit ([0-9a-f]+)', line, remote_sha):
            remote_words = line.split()
            remote_sha = remote_words[4].split(')')
            r_sha = remote_sha[0]
            r_sha_file = '%3d' % patchid + '_' + r_sha + '.patch'
            l_sha_file = '%3d' % patchid + '_' + l_sha + '.patch'
            patchid += 1

            print('----------------------')
            print('Comparing ' + l_sha[0:9] + ' ' + l_descr + '  AND  ' \
                  + r_sha[0:9])
            print('meld', r_sha_file, l_sha_file)
            call('git format-patch -1 ' + l_sha + ' --stdout > ' + l_sha_file,
                  shell=True)
            call('git format-patch -1 ' + r_sha + ' --stdout > ' + r_sha_file,
                  shell=True)
            call('meld ' + l_sha_file + ' ' + r_sha_file, shell=True)
            l_sha = ''
            l_descr = ''

    if re.match('^commit *', line):
        if l_sha != '':
            print('No cherry picked SHA1 in ' + l_sha[0:9] + ' ' + l_descr)
        words = line.split()
        l_sha = words[1]
        l_descr = ''