prepare-commit-msg

#!/bin/python3

# creates template for git-commit

from sys import argv, exit
from utils import *

commit_msg_file = open(argv[1], 'r+', encoding="utf8", errors='ignore')
commit_msg_split = readlines(commit_msg_file)
if commit_msg_split[0] != "": # don't change anything for git commit --amend
    exit(0)

def last_dir_or_filename(filepath):
    path_units = filepath.split('/')
    #### job addition ↓
    if filepath.startswith('api/python/core/') or filepath.startswith('api/python/cli/'):
        return 'baum-manager'
    elif 'tests/tests/' in filepath:
        return f'tests/{path_units[-1].split(".")[0]}'
    elif 'tests/api/' in filepath:
        return 'tests/api'
    elif 'tests/gui/' in filepath:
        return 'tests/gui'
    elif 'gitlab-ci/' in filepath:
        return 'ci'
    elif 'image/' in filepath:
        return 'image'
    elif 'web_server/' in filepath:
        return 'web'
    #### job addition ↑
    list_to_prefer_filename = ['src', 'scripts']
    last_dir = path_units[-2] if len(path_units) > 2 else None
    # heuristics: if we have a path dir/src/file.x, then it's likely that
    # the "dir" before "src" is the subsystem name. So use it.
    if last_dir == 'src':
        return path_units[-3]
    return (last_dir if (last_dir and last_dir not in list_to_prefer_filename) \
                     else path_units[-1])

def insert_comment_w_prev_commit_title(commit_msg_split, prev_commit_title):
    if not prev_commit_title:
        return
    i_fst_comment = find_i(commit_msg_split, lambda line: line.startswith('#'))
    if i_fst_comment is None:
        commit_msg_split[-1] = f'\n# {prev_commit_title}'
    else:
        commit_msg_split.insert(i_fst_comment, f'# {prev_commit_title}')

def get_prev_commit_stats():
    (prev_commit_stdout, exitcode) = run_cmd_no_fail('git log -1 --format=%s') # exitcode != 0 means repo that has no commits yet
    prev_commit_title = '' if exitcode != 0 else prev_commit_stdout[0]
    if exitcode == 0:
        (prev_commit_fst_changed_file, exitcode) = run_cmd_no_fail('git log -1 --name-only --pretty=format:')
        if exitcode != 0:
            raise Exception('git log failed!')
        return (prev_commit_title, prev_commit_fst_changed_file[0])
    return ('', '')

def maybe_repeat_title(fst_changed_file: str,
                       prev_commit_fst_changed_file: str,
                       prev_commit_title: str) -> str:
    prefix_curr = last_dir_or_filename(fst_changed_file)
    prefix_prev = prev_commit_title.split(':')[0]
    if fst_changed_file == prev_commit_fst_changed_file \
       and prefix_curr != prefix_prev:
        # this means we didn't guess the prefix correctly, and user had to choose a
        # different one. So take what user wrote back then
        return prefix_prev
    return prefix_curr

(prev_commit_title, prev_commit_fst_changed_file) = get_prev_commit_stats()
maybe_changed_files = run_cmd("git diff --name-only --cached") # an empty commits would lack changed files
fst_changed_file = maybe_changed_files[0] if maybe_changed_files else ''

# this one is a switch for my current job workflow
bug_number = (lambda: [maybe_bug := prev_commit_title.split(),
                       f' {maybe_bug[-1]}' if maybe_bug and maybe_bug[-1].startswith('#') else ''])()[-1]

prefix = maybe_repeat_title(fst_changed_file,
                            prev_commit_fst_changed_file,
                            prev_commit_title)
commit_msg_split[0] = prefix + f': {bug_number}'

insert_comment_w_prev_commit_title(commit_msg_split, prev_commit_title)

overwrite_file(commit_msg_file, commit_msg_split)