make error "duplicate" cheaper

[davidhewitt]

Change Summary

For #883 - replaces ValLineError::duplicate with ValLineError::into_owned which avoids the need to convert JsonInput to Python data when handling errors.

This is made possible by changing JsonInput to have Arc on the array and object variants. I used SmallVec inside those variants to avoid double-allocating for small lists & maps. Overall this shouldn't impact performance much, ideally will make it a bit tidier in #883.

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

Selected Reviewer: @samuelcolvin

[codecov]

Codecov Report

Merging #950 (d6d4088) into main (6769140) will decrease coverage by 0.03%.
The diff coverage is 89.13%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #950      +/-   ##
==========================================
- Coverage   93.83%   93.80%   -0.03%     
==========================================
  Files         105      105              
  Lines       15469    15468       -1     
  Branches       25       25              
==========================================
- Hits        14515    14510       -5     
- Misses        948      952       +4     
  Partials        6        6              

Files Changed	Coverage Δ
src/errors/line_error.rs	88.50% <63.63%> (-3.45%)	⬇️
src/lazy_index_map.rs	94.44% <92.30%> (-2.86%)	⬇️
src/errors/validation_exception.rs	93.68% <100.00%> (ø)
src/input/input_json.rs	91.83% <100.00%> (+0.02%)	⬆️
src/input/parse_json.rs	96.34% <100.00%> (ø)
src/input/return_enums.rs	85.27% <100.00%> (-0.03%)	⬇️
src/validators/function.rs	92.57% <100.00%> (ø)
src/validators/generator.rs	90.66% <100.00%> (ø)
src/validators/json.rs	97.77% <100.00%> (ø)

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[codspeed-hq]

CodSpeed Performance Report

Merging #950 will improve performances by 26.67%

_{Comparing dh/cheap-error-into-owned (d6d4088) with main (6769140)}

Summary

🔥 4 improvements
✅ 134 untouched benchmarks

Benchmarks breakdown

	Benchmark	main	dh/cheap-error-into-owned	Change
🔥	test_core_json_fs	929.8 µs	797.7 µs	+16.56%
🔥	test_list_of_ints_core_json	6.5 ms	5.2 ms	+24.63%
🔥	test_set_of_ints_core_json_duplicates	5.5 ms	4.3 ms	+26.67%
🔥	test_set_of_ints_core_json	7.3 ms	6.2 ms	+18.74%

[davidhewitt]

please review

[adriangb]

No changes to tests and good performance improvement sounds great to me!

[adriangb]

I assume we can have more than 8 items right? Is 8 just the default that gets allocated?

[davidhewitt]

Yes, how smallvec works is you pick a number of entries (in this case 8) which will be stored inline in the struct, and beyond that size it will instead use a heap allocation.