#!/usr/bin/env python3
from __future__ import annotations

import subprocess
import sys
from pathlib import Path

FORBIDDEN = {'a', 'an', 'the'}


def git_ls_python_files():
    result = subprocess.run(
        ['git', 'ls-files', '*.py'],
        capture_output=True,
        text=True,
        check=True,
    )
    return [Path(p) for p in result.stdout.splitlines()]


def is_test_file(path: Path) -> bool:
    name = path.name
    return (
        name.startswith('test_') or
        name.startswith('tests_') or
        name.endswith('_test.py')
    )


def has_forbidden_article(path: Path) -> bool:
    parts = path.stem.split('_')
    return any(part in FORBIDDEN for part in parts)


def main() -> int:
    for path in git_ls_python_files():
        if not is_test_file(path):
            continue

        if has_forbidden_article(path):
            print('ERROR: Forbidden article in test filename:')
            print(path)
            return 1

    return 0


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