typing.get_type_hints fails when passed a class with PEP 695 type parameters and PEP 563 is enabled #114053

mjog · 2024-01-14T11:51:18Z

Bug report

Bug description:

from __future__ import annotations

import typing

class Test[M]:
    attr: M

print(typing.get_type_hints(Test))

This fails with a NameError:

$ poetry run python3 pep_695_get_type_hints.py
Traceback (most recent call last):
  File "/home/mjog/pep_695_get_type_hints.py", line 8, in <module>
    print(typing.get_type_hints(Test))
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/typing.py", line 2197, in get_type_hints
    value = _eval_type(value, base_globals, base_locals)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/typing.py", line 393, in _eval_type
    return t._evaluate(globalns, localns, recursive_guard)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.12/typing.py", line 900, in _evaluate
    eval(self.__forward_code__, globalns, localns),
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<string>", line 1, in <module>
NameError: name 'M' is not defined

Although get_type_hints does not work with imported imported type aliases, this is not imported, so I would expect it to work. Further, the documentation for the function indicates using PEP 563 should /help/, but in this case it actually causes an error.

FWIW, removing the PEP 563 import works fine, giving:

{'attr': M}

Python version:

$ poetry run python3 --version
Python 3.12.0

CPython versions tested on:

3.12

Operating systems tested on:

Linux

Linked PRs

The text was updated successfully, but these errors were encountered:

mjog · 2024-01-15T07:37:50Z

Sorry, my now-hidden comment above is incorrect - it does work fine with pre-695 generic classes, I just had a typo in the code.

This is only an issue with PEP 695 type parameters in conjunction with PEP 563.

treykeown · 2024-01-19T23:31:01Z

+1, just ran into this as well.

AlexWaygood · 2024-04-17T20:01:58Z

I suppose the problem is probably that get_type_hints looks things up in the global scope but doesn't look things up in the new annotation scopes introduced by PEP-695. The old way of defining TypeVars doesn't suffer from this because TypeVars were defined in the global scope; now they aren't.

…pe_hints``

…ts`` (#118009) Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

…`get_type_hints`` (python#118009) (cherry-picked from commit 1e3e7ce) Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

…ype_hints`` (#118009) (#118104) Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

treykeown · 2024-04-25T15:14:44Z

I created a temporary workaround based off the fix by @AlexWaygood if anyone needs a hack around this in the meantime: https://gist.github.com/treykeown/65c45b3da330d2293c7fb9d2a46520ed

AlexWaygood · 2024-06-06T11:06:12Z

The bug was fixed in typing.get_type_hints, but the same bug also exists in inspect.get_annotations when eval_str=True is passed:

Python 3.14.0a0 (heads/main:eeb8f67f837, Jun  6 2024, 12:03:13) [Clang 15.0.0 (clang-1500.3.9.4)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from __future__ import annotations
>>> class test[M]:
...     attr: M
...     
>>> import inspect
>>> inspect.get_annotations(test, eval_str=True)
Traceback (most recent call last):
  File "<python-input-4>", line 1, in <module>
    inspect.get_annotations(test, eval_str=True)
    ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^
  File "/Users/alexw/dev/cpython/Lib/inspect.py", line 286, in get_annotations
    value if not isinstance(value, str) else eval(value, globals, locals)
                                             ~~~~^^^^^^^^^^^^^^^^^^^^^^^^
  File "<string>", line 1, in <module>
NameError: name 'M' is not defined

….get_annotations`

…P 695 and PEP 563

…nnotations` (#120270)

….get_annotations` (pythonGH-120270) (cherry picked from commit 42351c3) Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

…t.get_annotations` (GH-120270) (#120475) gh-114053: Fix bad interaction of PEP 695, PEP 563 and `inspect.get_annotations` (GH-120270) (cherry picked from commit 42351c3) Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

…t.get_annotations` (GH-120270) (#120474) gh-114053: Fix bad interaction of PEP 695, PEP 563 and `inspect.get_annotations` (GH-120270) (cherry picked from commit 42351c3) Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

…and PEP 563 (#120272)

…P 695 and PEP 563 (pythonGH-120272) (cherry picked from commit 2d3187b) Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

…EP 695 and PEP 563 (GH-120272) (#121003) Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

…EP 695 and PEP 563 (GH-120272) (#121004) Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

….get_annotations` (python#120270)

…P 695 and PEP 563 (python#120272)

….get_annotations` (python#120270)

…P 695 and PEP 563 (python#120272)

….get_annotations` (python#120270)

…P 695 and PEP 563 (python#120272)

mjog added the type-bug An unexpected behavior, bug, or error label Jan 14, 2024

Eclips4 added topic-typing 3.12 only security fixes 3.13 bugs and security fixes labels Jan 14, 2024

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mjog changed the title ~~typing.get_type_hints fails when passed a class with PEP 695 type parameters and PEP 563 is enabled~~ typing.get_type_hints fails when passed a generic class and PEP 563 is enabled Jan 14, 2024

mjog changed the title ~~typing.get_type_hints fails when passed a generic class and PEP 563 is enabled~~ typing.get_type_hints fails when passed a class with PEP 695 type parameters and PEP 563 is enabled Jan 15, 2024

aspizu mentioned this issue Apr 17, 2024

Cannot introspect generic structs, possibly bug in python stdlib. jcrist/msgspec#666

Closed

AlexWaygood added a commit to AlexWaygood/cpython that referenced this issue Apr 17, 2024

pythongh-114053: Fix bad interaction of PEP-695, PEP-563 and ``get_ty…

c76bfc0

…pe_hints``

bedevere-app bot mentioned this issue Apr 17, 2024

gh-114053: Fix bad interaction of PEP-695, PEP-563 and get_type_hints #118009

Merged

AlexWaygood added a commit that referenced this issue Apr 19, 2024

gh-114053: Fix bad interaction of PEP-695, PEP-563 and ``get_type_hin…

1e3e7ce

…ts`` (#118009) Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

bedevere-app bot mentioned this issue Apr 19, 2024

[3.12] gh-114053: Fix bad interaction of PEP-695, PEP-563 and get_type_hints (#118009) #118104

Merged

AlexWaygood added a commit that referenced this issue Apr 19, 2024

[3.12] gh-114053: Fix bad interaction of PEP-695, PEP-563 and ``get_t…

5430f61

…ype_hints`` (#118009) (#118104) Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

AlexWaygood closed this as completed Apr 19, 2024

AlexWaygood added the stdlib Python modules in the Lib dir label Apr 19, 2024

AlexWaygood mentioned this issue Apr 30, 2024

TypeError: _eval_type() missing 1 required positional argument: 'type_params' with import module #118418

Closed

This was referenced May 21, 2024

Reinstate typevar variable for config_validation helper home-assistant/core#117829

Closed

Add typing.get_type_hints backport python/typing_extensions#410

Closed

AlexWaygood reopened this Jun 6, 2024

AlexWaygood self-assigned this Jun 6, 2024

AlexWaygood added a commit to AlexWaygood/cpython that referenced this issue Jun 8, 2024

pythongh-114053: Fix bad interaction of PEP 695, PEP 563 and `inspect…

ac5fd65

….get_annotations`

bedevere-app bot mentioned this issue Jun 8, 2024

gh-114053: Fix bad interaction of PEP 695, PEP 563 and inspect.get_annotations #120270

Merged

AlexWaygood added a commit to AlexWaygood/cpython that referenced this issue Jun 8, 2024

pythongh-114053: Fix another edge case involving get_type_hints, PE…

879abeb

…P 695 and PEP 563

bedevere-app bot mentioned this issue Jun 8, 2024

gh-114053: Fix another edge case involving get_type_hints, PEP 695 and PEP 563 #120272

Merged

AlexWaygood added a commit that referenced this issue Jun 13, 2024

gh-114053: Fix bad interaction of PEP 695, PEP 563 and `inspect.get_a…

42351c3

…nnotations` (#120270)

bedevere-app bot mentioned this issue Jun 13, 2024

[3.13] gh-114053: Fix bad interaction of PEP 695, PEP 563 and inspect.get_annotations (GH-120270) #120474

Merged

bedevere-app bot mentioned this issue Jun 13, 2024

[3.12] gh-114053: Fix bad interaction of PEP 695, PEP 563 and inspect.get_annotations (GH-120270) #120475

Merged

AlexWaygood added a commit that referenced this issue Jun 25, 2024

gh-114053: Fix another edge case involving get_type_hints, PEP 695 …

2d3187b

…and PEP 563 (#120272)

bedevere-app bot mentioned this issue Jun 25, 2024

[3.13] gh-114053: Fix another edge case involving get_type_hints, PEP 695 and PEP 563 (GH-120272) #121003

Merged

bedevere-app bot mentioned this issue Jun 25, 2024

[3.12] gh-114053: Fix another edge case involving get_type_hints, PEP 695 and PEP 563 (GH-120272) #121004

Merged

AlexWaygood closed this as completed Jun 25, 2024

AlexWaygood added a commit that referenced this issue Jun 25, 2024

[3.13] gh-114053: Fix another edge case involving get_type_hints, P…

f4f8a71

…EP 695 and PEP 563 (GH-120272) (#121003) Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

AlexWaygood added a commit that referenced this issue Jun 25, 2024

[3.12] gh-114053: Fix another edge case involving get_type_hints, P…

a85241d

…EP 695 and PEP 563 (GH-120272) (#121004) Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

mrahtz pushed a commit to mrahtz/cpython that referenced this issue Jun 30, 2024

pythongh-114053: Fix bad interaction of PEP 695, PEP 563 and `inspect…

6211f9d

….get_annotations` (python#120270)

mrahtz pushed a commit to mrahtz/cpython that referenced this issue Jun 30, 2024

pythongh-114053: Fix another edge case involving get_type_hints, PE…

7357059

…P 695 and PEP 563 (python#120272)

noahbkim pushed a commit to hudson-trading/cpython that referenced this issue Jul 11, 2024

pythongh-114053: Fix bad interaction of PEP 695, PEP 563 and `inspect…

d87297d

….get_annotations` (python#120270)

noahbkim pushed a commit to hudson-trading/cpython that referenced this issue Jul 11, 2024

pythongh-114053: Fix another edge case involving get_type_hints, PE…

7dcc9e0

…P 695 and PEP 563 (python#120272)

estyxx pushed a commit to estyxx/cpython that referenced this issue Jul 17, 2024

pythongh-114053: Fix bad interaction of PEP 695, PEP 563 and `inspect…

6171713

….get_annotations` (python#120270)

estyxx pushed a commit to estyxx/cpython that referenced this issue Jul 17, 2024

pythongh-114053: Fix another edge case involving get_type_hints, PE…

f62761c

…P 695 and PEP 563 (python#120272)

Parnassius mentioned this issue Sep 14, 2024

Calling typing.get_type_hints with a class or instance method with PEP 695 type parameters fails if PEP 563 is enabled #124089

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typing.get_type_hints fails when passed a class with PEP 695 type parameters and PEP 563 is enabled #114053

typing.get_type_hints fails when passed a class with PEP 695 type parameters and PEP 563 is enabled #114053

mjog commented Jan 14, 2024 •

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mjog commented Jan 15, 2024 •

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treykeown commented Jan 19, 2024

AlexWaygood commented Apr 17, 2024

treykeown commented Apr 25, 2024

AlexWaygood commented Jun 6, 2024

typing.get_type_hints fails when passed a class with PEP 695 type parameters and PEP 563 is enabled #114053

typing.get_type_hints fails when passed a class with PEP 695 type parameters and PEP 563 is enabled #114053

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mjog commented Jan 14, 2024 • edited by bedevere-app bot Loading

Bug report

Bug description:

CPython versions tested on:

Operating systems tested on:

Linked PRs

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treykeown commented Jan 19, 2024

AlexWaygood commented Apr 17, 2024

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