perf(parser/tokens): pre-allocate capacity for tokens

[overlookmotel]

Perf optimization to parsing with tokens. Pre-allocate sufficient capacity in the ArenaVec<Token> so it doesn't need to grow during the parsing process.

Up to 22% perf improvement on benchmarks for parsing with tokens.

[overlookmotel]

• perf(estree): use CodeBuffer::print_indent #19727 : 2 dependent PRs (#19744 , #19760 )
• perf(estree/tokens): serialize tokens while visiting AST #19726
• perf(estree/tokens): serialize with ESTree not serde #19725
• feat(estree): oxc_estree crate export config and formatter types #19724
• refactor(estree/tokens): convert tokens spans before AST spans #19723
• refactor(estree/tokens): simplify code #19722
• perf(estree/tokens): do not branch on presence of override twice #19721
• refactor(estree/tokens): move logic for excluding legacy identifiers into visitor #19720
• perf(estree/tokens): replace hash map with Vec #19718
• perf(estree/tokens): replace multiple hash sets into a single hash map #19716
• refactor(estree/tokens): replace stored token when re-lexing #19698
• perf(parser): remove branches from finish_next_inner #19695
• perf(parser): remove const generic param from finish_next_inner #19684
• feat(parser): add LexerConfig::TOKENS_METHOD_IS_STATIC const #19683
• docs(parser): improve doc comments for ParserConfig and LexerConfig #19682
• refactor(estree/tokens): use wildcard import for AST types #19681
• test(estree): ESTree conformance check files with hashbangs #19680
• fix(estree/tokens): reverse field order of regex object in tokens #19679
• perf(estree/tokens): serialize tokens to compact JSON #19572
• ci(benchmarks): correct comment #19650
• perf(parser/tokens): pre-allocate capacity for tokens #19543 👈 (View in Graphite)
• fix(estree/tokens): generate tokens for files with BOM #19535
• refactor(estree/tokens): combine collect_token_context into to_estree_tokens_json #19534
• refactor(estree): reorder tokens code #19533
• refactor(coverage): standardize ESTree tokens testing functions #19532
• perf(linter/plugins): remove typescript from bundle #19531
• docs(linter/plugins): correct doc comments for initTokens #19530
• refactor(linter/plugins): combine functions for getting tokens #19529
• ci(benchmarks): benchmark parser with tokens and ESTree tokens conversion #19649
• perf(linter/plugins): use Oxc tokens in plugins #19498
• test(estree/tokens): do not skip tokens conformance tests for files with hashbangs #19643
• fix(estree): fix tokens for JSX #19524
• perf(parser): introduce ParserConfig #19637
• feat(parser,estree,coverage): collect tokens in parser and convert to ESTree format #19497
• feat(coverage): add estree token conformance scaffolding #19496
• fix(tasks/coverage): bring back acorn-jsx estree testing #19516 : 1 other dependent PR (#19515 )
• chore(submodules): update submodule SHAs to latest commits #19518
• main

---

How to use the Graphite Merge Queue

Add either label to this PR to merge it via the merge queue:

• 0-merge - adds this PR to the back of the merge queue
• hotfix - for urgent hot fixes, skip the queue and merge this PR next

You must have a Graphite account in order to use the merge queue. Sign up using this link.

An organization admin has enabled the Graphite Merge Queue in this repository.

Please do not merge from GitHub as this will restart CI on PRs being processed by the merge queue.

This stack of pull requests is managed by Graphite. Learn more about stacking.

[codspeed-hq]

Merging this PR will improve performance by 22.2%

⚡ 4 improved benchmarks
✅ 48 untouched benchmarks
⏩ 3 skipped benchmarks¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	parser_tokens[binder.ts]	4.5 ms	3.8 ms	+17.67%
⚡	Simulation	parser_tokens[react.development.js]	1.8 ms	1.5 ms	+22.2%
⚡	Simulation	parser_tokens[RadixUIAdoptionSection.jsx]	98.5 µs	94.3 µs	+4.48%
⚡	Simulation	parser_tokens[cal.com.tsx]	33.4 ms	30.3 ms	+10.44%

---

_{Comparing om/02-19-perf_parser_tokens_pre-allocate_capacity_for_tokens (b0fa937) with om/02-18-fix_estree_tokens_generate_tokens_for_files_with_bom (142e46b)}

Footnotes

1. 3 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. ↩

[graphite-app]

Merge activity

• Feb 24, 1:42 PM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Feb 24, 1:50 PM UTC: Merged by the Graphite merge queue.