experiment with "ref" form of extra

[davidhewitt]

Change Summary

Experiment whether avoiding taking ownership of extra can aid performance. Not ready, pushing for codspeed feedback.

Related issue number

N/A

Checklist

• Unit tests for the changes exist
• Documentation reflects the changes where applicable
• Pydantic tests pass with this pydantic-core (except for expected changes)
• My PR is ready to review, please add a comment including the phrase "please review" to assign reviewers

[codecov]

Codecov Report

❌ Patch coverage is 0% with 60 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/serializers/type_serializers/function.rs	0.00%	60 Missing ⚠️

📢 Thoughts on this report? Let us know!

[codspeed-hq]

CodSpeed Performance Report

Merging #1786 will not alter performance

_{Comparing davidhewitt:dh/owned-extra (0fe0b40) with main (1cd5ee3)}

Summary

✅ 161 untouched

[davidhewitt]

I realise there is no benchmark for this serialization pathway, will add one.

[davidhewitt]

The signal is slightly too small to show here, this is a ~5% improvement on the wrap serializer performance according to codspeed.