winUser.WinTimer: ensure timerFunc is correctly wrapped as a TIMERPROC even when None.

[michaelDCurran]

Link to issue number:

Fixes #18907
Fixes #18914

Summary of the issue:

Tightening up ctypes definitions for 64 bit means that ctypes may be more picky with what can be passed as an argument. In particular passing None to an argument that should be a callback now will fail.
The correct way is now to pass Functype(0) where Functype is the callback's ctypes definition.
So far just one call has been identified in #18914: SetTimer takes a TIMERPROC.

Description of user facing changes:

None.

Description of developer facing changes:

Description of development approach:

winUser.WinTimer now ensures that timerFunc is already, or is converted to, a TIMERPROC. Specifically ensuring None is converted to TIMERPROC(0).

Testing strategy:

• The author of The new winBindings module is not compatible with optional parameters when setting Win32 API ctypes function signatures, causing a large number of function calls to fail. #18914 should confirm this fix.

Known issues with pull request:

None known.

Code Review Checklist:

• Documentation:
  • Change log entry
  • User Documentation
  • Developer / Technical Documentation
  • Context sensitive help for GUI changes
• Testing:
  • Unit tests
  • System (end to end) tests
  • Manual testing
• UX of all users considered:
  • Speech
  • Braille
  • Low Vision
  • Different web browsers
  • Localization in other languages / culture than English
• API is compatible with existing add-ons.
• Security precautions taken.

[Copilot]

Pull Request Overview

This PR fixes a ctypes compatibility issue where passing None as a timer callback function to SetTimer fails in 64-bit environments due to stricter type checking. The fix ensures that timer functions are properly wrapped as TIMERPROC types, with None being converted to TIMERPROC(0).

• Adds type conversion logic to handle different timerFunc input types
• Ensures None values are properly converted to typed null function pointers
• Maintains backward compatibility while fixing 64-bit ctypes strictness

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[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

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[hwf1324]

Run from source, confirmed #18907 has been fixed.