perf(transformer/arrow-function): reduce string comparisons

[overlookmotel]

Experiment. Try avoiding string comparisons in most cases for IdentifierReferences and BindingIdentifiers. Not sure if this will be faster or not.

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[overlookmotel]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• perf(transformer/arrow-function): reduce string comparisons #7318 👈 (View in Graphite)
• test(transformer/async-to-generator): failing test for nested supers #7314
• perf(transformer/arrow-functions): move arguments transform checks to aid inlining #7322
• perf(transformer/arrow-functions): store state of whether arguments needs transform #7321
• refactor(transformer/arrow-function): comments on possible improvement #7320
• refactor(transformer/arrow-function): reserve correct capacity for Vec #7319
• perf(transformer/arrow-function): create super method binding names lazily #7313
• refactor(transformer/arrow-functions): use IndexMap for super getter/setters #7317
• perf(transformer/arrow-function): optimize generate_super_binding_name #7312
• fix(transformer/arrow-function): handle unicode when capitalizing property name #7311
• refactor(transformer/arrow-function): generate_super_binding_name take &str and &TraverseCtx #7310
• fix(transformer/async-to-generator): arguments isn't correct after transformation #7234
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #7318 will degrade performances by 10.07%

_{Comparing 11-16-perf_transformer_arrow-function_reduce_string_comparisons (2d0e72c) with main (cf3415b)}

Summary

❌ 3 regressions
✅ 27 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	11-16-perf_transformer_arrow-function_reduce_string_comparisons	Change
❌	transformer[antd.js]	45.3 ms	48.7 ms	-6.82%
❌	transformer[checker.ts]	18 ms	20 ms	-10.07%
❌	transformer[pdf.mjs]	6.6 ms	7 ms	-6.43%

[overlookmotel]

The benchmarks above are misleading. Codspeed is comparing to main, instead of PR below in stack. So result above includes the perf hit of #7234.

This does appear to help very marginally, but not enough to be worthwhile.