An extension for flake8 that validates functions names, decomposition and conformity with annotations. The plugin also has some validations of deal contracts.

This plugin helps to provide better naming for functions. The validations are based on my articles:

• Python functions naming: an algorithm
• Python functions naming: 10 tips

deal-related validations are enabled only if deal is installed. They are disabled otherwise.

pip install flake8-functions-names

def is_user_banned(user: User) -> str:
    return 'is_banned' if user.id in BANNED_USERS else 'not_banned'

def save_user(user: User) -> None:
    user.save()

Usage:

$ flake8 test.py
text.py:1:35: FNE001 Name of the function says that it should return bool-like, but it returns str
text.py:4:4: FNE003 Name of the function uses "save", but not uses "to"

Tested on Python 3.8+ and flake8 3.9+.