python / python/mypy

[comparison-overlap] error on `Type[Any]` typed var compared with `Any`

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bug
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Python
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Description

Bug Report

Since mypy version 1.11 the comparison-overlap error occurred in the following code. This error did not occur in older versions that I have used before.

To Reproduce

from typing import Type, Any

def test(tp: Type[Any]) -> None:
    if tp == Any:
        return

Expected Behavior
No error

Actual Behavior

error: Non-overlapping equality check (left operand type: "type[Any]", right operand type: "<typing special form>") 
[comparison-overlap]
        if tp == Any:
           ^~~~~~~~~~

Your Environment

  • Mypy version used: 1.11.1
  • Mypy command-line flags: --strict-equality
  • Mypy configuration options from mypy.ini (and other config files): none
  • Python version used: 3.12.4

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Run the provided Python 3.12.4 reproducer with mypy 1.11.1 and --strict-equality, then trace how comparison-overlap handles Type[Any] compared with Any. Add regression coverage for this case and verify that the diagnostic is no longer emitted while other strict-equality checks remain intact.

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
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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