Warn about using F from magic_filter instead of aiogram one

[evgfilim1]

Problem

Sometimes people may be confused why the filter won't pass when they have .as_("arg") at the end of F-expression. The reason is they use from magic_filter import F instead of from aiogram import F. The one that provided by aiogram has an additional method .as_(key: str) that is useful only with aiogram filters: it returns a dictionary if the filter passes, then the result is added to handler kwargs by aiogram.

Possible solution

Throw a warning if the user is using F provided by magic_filter

Adding an isinstance(self.callback, aiogram.utils.MagicFilter) check here would be enough

aiogram/aiogram/dispatcher/event/handler.py

Lines 50 to 56 in e7cee43

	def __post_init__(self) -> None:
	# TODO: Make possibility to extract and explain magic from filter object.
	# Current solution is hard for debugging because the MagicFilter instance can't be extracted
	if isinstance(self.callback, MagicFilter):
	# MagicFilter instance is callable but generates only "CallOperation" instead of applying the filter
	self.callback = self.callback.resolve
	super().__post_init__()

Alternatives

No response

Code example

from aiogram import Router
from aiogram.types import Message, User
from magic_filter import F

# The filter below won't pass as `User` object has no attribute `as_`,
#  so the handler will never run
@router.message(F.from_user.as_("user"))
# Warning: You are using F provided by magic_filter directly, but
#  it lacks .as_() extension. Please change the import statement:
#  `from magic_filter import F` -> `from aiogram import F` to silence
#  this warning.
async def whoami(message: Message, user: User) -> None:
    return message.reply("You are {user.first_name}")

Additional information

No response