python / python/cpython

partial __getstate__ wrong (?)

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extension-modules type-bug
Dominant language
Python
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Description

Bug report

Bug description:

The native _functools.partial type __getstate__ will return its __dict__. That will not include func, args or keywords.

This is different from the pure Python implementation of functools.partial (link), where it will return the slots, i.e. the state includes func, args or keywords.

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Contributor guide

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First steps

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Compare the native _functools.partial getstate behavior with the pure Python functools.partial implementation linked in the issue, focusing on whether func, args, and keywords are included. Trace the existing partial implementation and tests, then add a regression test that defines the expected state and confirms the native and pure Python behaviors are consistent.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
backend
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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