Required/NotRequired don't work with __future__.annotations

Required/NotRequired aren't properly detected when from __future__ import annotations is used, leading to incorrect __required_keys__/__optional_keys__ sets.

Reproduced with 4.3.0.

from __future__ import annotations  # comment this line out and things work correctly
from typing_extensions import NotRequired, TypedDict

class Test(TypedDict):
    a: int
    b: NotRequired[int]

assert Test.__required_keys__ == {"a"}
assert Test.__optional_keys__ == {"b"}

$ python test.py
Traceback (most recent call last):
  File "/home/jcristharif/Code/test.py", line 8, in <module>
    assert Test.__required_keys__ == {"a"}
AssertionError

What Python version are you running? Does this reproduce with typing too on Python 3.11?

I don't have (easy) access to a 3.11 build, but it reproduces with 4.3.0 on both 3.10 and 3.9.

I can reproduce using typing.TypedDict and typing.NotRequired on the CPython main branch (3.12), so I assume it reproduces on 3.11 using the stdlib typing module as well.

just ran into this issue with 4.3.0 and python 3.7.6 - any fix in the works? thanks!

So is this fixed by #60 or not? It seems to be an issue with the upstream cpython typing module as well -- did someone already file an issue there? Please link it here.

#60 would fix this in simple cases, but I think it will cause more problems than it solves. I'm inclined to wontfix this. Maybe we can revisit once there's a resolution on the PEP 563/649 saga.

It's fine to not want to solve this for now. In fact one could argue that, since the point of from __future__ import annotations is not to incur runtime costs, you get what you ask for. (Not sure if that's totally fair, but it's a possible POV.)

I'm closing this here in favor of python/cpython#97727. It seems that the consensus is that it's too complex to fix and will go away by itself at some distant point in the future when the future import isn't required anymore.

I now had this problem too. Inspired by python/cpython#97727 (comment) I made these 4 utility functions to get the correct __required_keys__ / __optional_keys__, extend for __readonly_keys__ in a similar way.

from typing_extensions import NotRequired, Required, get_origin, get_type_hints

def get_explicit_required_keys(cls):
    return {k for k, v in get_type_hints(cls, include_extras=True).items() if get_origin(v) is Required}

def get_explicit_unrequired_keys(cls):
    return {k for k, v in get_type_hints(cls, include_extras=True).items() if get_origin(v) is NotRequired}

def get_required_keys(cls):
    return cls.__required_keys__ - get_explicit_unrequired_keys(cls)

def get_optional_keys(cls):
    return cls.__optional__keys - get_explicit_required_keys(cls)

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`Required`/`NotRequired` don't work with `future.annotations` #55

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Required/NotRequired don't work with __future__.annotations #55

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JelleZijlstra commented on Jul 11, 2022

jcrist commented on Jul 11, 2022

AlexWaygood commented on Jul 12, 2022

yixun-alpha commented on Sep 2, 2022

gvanrossum commented on Sep 2, 2022

JelleZijlstra commented on Sep 2, 2022

gvanrossum commented on Sep 2, 2022

srittau commented on Sep 2, 2024

Daraan commented on Mar 28, 2025

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`Required`/`NotRequired` don't work with `future.annotations` #55