python / python/mypy

`Expression type contains "Any"` false positive when casting tuple

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bug topic-disallow-any
Dominant language
Python
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Description

from typing import cast

cast(tuple[int, int], tuple(value for value in [1, 2]))
main.py:3: error: Expression type contains "Any" (has type "Generator[Any, None, None]")  [misc]

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Research direction

Reproduce the report from main.py using the linked mypy playground and the shown strict flags. Trace how the tuple comprehension is inferred before cast() and how disallow-any-expr reports it. Done means the example no longer produces a false-positive Expression type contains "Any" error while genuine Any expressions remain reported.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
compilers
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
38/100

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