git-svn-log

#!/usr/bin/env python

import argparse, subprocess, sys, re


def resolve_glob_filename(filename):
    resolve_glob_filename = subprocess.check_output(
        'git log -n1 --name-only --format=oneline --'.split() + [filename], text = True).split('\n')
    commit    = resolve_glob_filename[0].split()[0]
    full_path = resolve_glob_filename[1]
    return commit, full_path

re_svn_id = re.compile(r'git-svn-id: (.*)@([0-9]+) ([0-9a-f-]+)$')

def parse_svn_info(log_message):
    ma = re_svn_id.search(log_message)
    return ma.groups()

def get_svn_info(commit):
    return parse_svn_info(
        subprocess.check_output('git cat-file -p'.split() + [commit], text = True))


parser = argparse.ArgumentParser(description = 'display combined history from git log and svn log')
parser.add_argument('filename')
args = parser.parse_args()

commit, full_path = resolve_glob_filename(args.filename)
base_url, rev, repo_id = get_svn_info(commit)
rev = int(rev)

svn_log_command = ['svn', 'log', '-v', f'{base_url}/{full_path}@{rev}']
print(' '.join(svn_log_command))

subprocess.check_call(svn_log_command)