flake8-functions-names

flake8-functions-names

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.

Installation

pip install flake8-functions-names

Example

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+.

Error codes

Error code	Description
FNE001	Name of the function says that it should return bool-like1, but it returns actual_type
FNE002	The method has a @property decorator, but has a verb in it's name (verb)
FNE003	Name of the function uses save, but not uses to
FNE004	Name of the function uses load, but not uses from
FNE005	Return type of the function is bool-like1, but the name doesn't show it
FNE006	Name of function says, that it works with data, so it should be pure, but it has no @deal.pure()
FNE007	and is not recommended in functions names
FNE008	Name of functions ends with it's first argument name

Footnotes

• bool-like return types: bool, TypeGuard ↩ ↩²