perf(transformer): avoid unneccessary vec allocation

[camc314]

avoid collecting into a vec when extends can accept an iterator instead

[camc314]

• perf(transformer): avoid unneccessary vec allocation #17270 👈 (View in Graphite)
• main

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[Copilot]

Pull request overview

This PR optimizes performance by eliminating an unnecessary intermediate Vec allocation. Instead of collecting an iterator into a Vec and then extending another collection with it, the code now directly extends with the iterator, as the extend method accepts any type implementing IntoIterator.

Key Changes:

• Removed intermediate .collect::<Vec<_>>() call when extending temp_decls
• Simplified code by directly passing the iterator to extend()

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[codspeed-hq]

CodSpeed Performance Report

Merging #17270 will not alter performance

_{Comparing c/12-22-perf_transformer_avoid_unneccessary_vec_allocation (5634053) with main (4ac23e1)}

Summary

✅ 38 untouched
⏩ 7 skipped¹

Footnotes

1. 7 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Dunqing]

Merge activity

• Dec 22, 12:44 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Dec 22, 12:44 PM UTC: Dunqing added this pull request to the Graphite merge queue.
• Dec 22, 12:50 PM UTC: Merged by the Graphite merge queue.