Git commit hook to check for lines with "TODO" in them

todo-check.py

#!/usr/bin/python
import logging
import re
import sys

import envoy


def _exec_git(cmd, args=''):
    cmd = 'git {0} --color=never {1}'.format(cmd, args)
    logging.debug('Calling: {0}'.format(cmd))
    res = envoy.run(cmd)
    if res.status_code != 0:
        raise Exception('Command \'{0}\' failed: {1}'.format(cmd, res.std_err))
    return res


def get_diff():
    res = _exec_git('diff', '--cached HEAD')
    return res.std_out.splitlines()


def check_commit():
    errors = 0
    diff = get_diff()
    file_re = re.compile('^\+\+\+ b\/(.+)$')
    diff_re = re.compile('^@@ -[0-9]+,[0-9]+ \+([0-9]+),[0-9]+ @@')
    regex = re.compile('^\+.*TODO.*')
    filename = None
    position = 0
    for line in diff:
        # read diff line, like '@@ -5,6 +5,18 @@'
        match = diff_re.match(line)
        if match:
            position = int(match.groups()[0])
            logging.debug('Hunk position: {0}'.format(position))
            continue

        # read file line, like '+++ b/foo/bar/file.py'
        file_match = file_re.match(line)
        if file_match:
            filename = file_match.groups()[0]
            logging.debug('Filename: {0}'.format(filename))
            continue

        match = regex.match(line)
        if match:
            print '{0}:{1}: Line has TODO statement: {0}'.format(filename, position, line)
            errors += 1

        if not line.startswith('-'):
            position += 1

    return errors

def main():
    logging.basicConfig()
    return check_commit()

if __name__ == '__main__':
    sys.exit(main())