[False positive] "type[...]" has no attribute "__metadata__" (and __origin__)
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Description
Bug Report
Please consider the working script below:
from typing import Annotated
T = Annotated[int, 'ops']
if __name__ == '__main__':
print(T.__origin__)
# ^^^^^^^^^^^^^^^^^^^----- error: "type[int]" has no attribute "__origin__" [attr-defined]
print(T.__metadata__)
# ^^^^^^^^^^^^^^^^^^^----- error: "type[int]" has no attribute "__metadata__" [attr-defined]
where mypy generates 2 errors.
(.venv314) PS C:\Users\XXXXXX\YYYYY> mypy --strict tstann.py
tstann.py:7: error: "type[int]" has no attribute "__origin__" [attr-defined]
tstann.py:9: error: "type[int]" has no attribute "__metadata__" [attr-defined]
Found 2 errors in 1 file (checked 1 source file)
Expected Behavior
Absence of these errors
Your Environment
- Mypy version used: 2.1.0 from pypi
- Mypy command-line flags: --strict
- Mypy configuration options from
mypy.ini(and other config files): absent - Python version used: 3.14.5
- Windows 11
Additionally
These attributes are documented in https://docs.python.org/3/library/typing.html#typing.Annotated
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by running the reported tstann.py example with mypy --strict and compare the diagnostics for Annotated[int, 'ops'] with the documented Annotated attributes. The payload names no implementation file or existing test; done means the two false-positive attr-defined errors are absent while the relevant behavior remains checked by a regression test.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- devtools
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Quiet
- Clarity
- Mostly clear
- Newbie friendliness
- 55/100