Unhelpful error message for A.__annotate__('x')

[PierreQuentel]

Bug report

Bug description:

Python 3.14.0b2 (tags/v3.14.0b2:12d3f88, May 26 2025, 13:55:44) [MSC v.1943 64 bit (AMD64)] on win32
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>>> class A:
...     x: int
...
>>> A.__annotate__('x')
Traceback (most recent call last):
  File "<python-input-1>", line 1, in <module>
    A.__annotate__('x')
    ~~~~~~~~~~~~~~^^^^^
  File "<python-input-0>", line 1, in __annotate__
    class A:

TypeError: '>' not supported between instances of 'str' and 'int'
>>>

The message should be something like

TypeError: __annotate__() argument must be int, not str

CPython versions tested on:

3.14

Operating systems tested on:

Windows

[JelleZijlstra]

I don't think we should change anything here.

Errors like this are common for standard library functions implemented in Python. For example:

>>> inspect.stack(context="x")
Traceback (most recent call last):
  File "<python-input-2>", line 1, in <module>
    inspect.stack(context="x")
    ~~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/Users/jelle/py/cpython/Lib/inspect.py", line 1655, in stack
    return getouterframes(sys._getframe(1), context)
  File "/Users/jelle/py/cpython/Lib/inspect.py", line 1630, in getouterframes
    traceback_info = getframeinfo(frame, context)
  File "/Users/jelle/py/cpython/Lib/inspect.py", line 1589, in getframeinfo
    if context > 0:
       ^^^^^^^^^^^
TypeError: '>' not supported between instances of 'str' and 'int'

Users usually shouldn't be calling __annotate__ directly anyway; there is higher-level functionality available in annotationlib. I'd welcome contributions making error handling annotationlib better.

Last, adding special-case handling for this case (something like if not isinstance(format, int): raise TypeError(...)) would increase code size for all annotate functions.

[PierreQuentel]

Ok, thanks for the reply. I close the issue.