perf(ast, codegen, transformer): avoid allocations when converting RegExpFlags to string

[overlookmotel]

In various places, we were using RegExpFlags::to_string when we want a &str. This creates a String temporarily, which is an unnecessary allocation.

Add RegExpFlags::to_inline_string method which creates an InlineString instead, without any allocation. Use this method wherever we convert from RegExpFlags to &str.

The downside of this change is that oxc_ast gains a dependency on oxc_data_structures. Personally, I don't think this is so bad, as oxc_data_structures is a pretty lightweight crate, containing only quite minimalist data structures. The code is mostly comments! However, what we could do is put each component of oxc_data_structures behind it's own feature, so consumers can take only what they need.

[overlookmotel]

• perf(mangler): use shorter InlineString #9552
• refactor(ast/estree): simplify serializing RegExpLiterals #9551
• perf(ast, codegen, transformer): avoid allocations when converting RegExpFlags to string #9550 👈 (View in Graphite)
• feat(data_structures): move InlineString into oxc_data_structures crate #9549
• refactor(ast): RegExpFlags::to_string return flags in alphabetical order #9548
• feat(ast/estree): Property have consistent field order #9547
• feat(ast/estree): ESTree AST ExportNamedDeclaration always have attributes field #9546
• ci(benchmarks): benchmark NAPI parser #9519
• fix(ast/estree): raw transfer support showSemanticErrors option #9522
• test(ast/estree): speed up raw transfer tests #9521
• feat(ast/estree)!: option to return JS-only AST #9520
• feat(ast/estree): raw transfer (experimental) #9516
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #9550 will create unknown performance changes

_{Comparing 03-04-perf_ast_codegen_transformer_avoid_allocations_when_converting_regexpflags_to_string (6b4a8c6) with main (3e4f909)}

Summary

🆕 39 new benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
🆕	parser_napi[RadixUIAdoptionSection.jsx]	N/A	4.8 ms	N/A
🆕	parser_napi[pdf.mjs]	N/A	1.8 s	N/A
🆕	parser_napi_raw[RadixUIAdoptionSection.jsx]	N/A	1.3 ms	N/A
🆕	parser_napi_raw[cal.com.tsx]	N/A	699.8 ms	N/A
🆕	parser_napi_raw[checker.ts]	N/A	1.1 s	N/A
🆕	parser_napi_raw[pdf.mjs]	N/A	266.6 ms	N/A
🆕	codegen[checker.ts]	N/A	23.1 ms	N/A
🆕	codegen_sourcemap[checker.ts]	N/A	66.2 ms	N/A
🆕	isolated-declarations[vue-id.ts]	N/A	57.9 ms	N/A
🆕	lexer[RadixUIAdoptionSection.jsx]	N/A	20.8 µs	N/A
🆕	lexer[antd.js]	N/A	24.1 ms	N/A
🆕	lexer[cal.com.tsx]	N/A	5.7 ms	N/A
🆕	lexer[checker.ts]	N/A	14.5 ms	N/A
🆕	lexer[pdf.mjs]	N/A	3.8 ms	N/A
🆕	linter[RadixUIAdoptionSection.jsx]	N/A	2.7 ms	N/A
🆕	linter[cal.com.tsx]	N/A	1.2 s	N/A
🆕	linter[checker.ts]	N/A	2.9 s	N/A
🆕	mangler[antd.js]	N/A	16 ms	N/A
🆕	mangler[react.development.js]	N/A	295.2 µs	N/A
🆕	mangler[typescript.js]	N/A	39.7 ms	N/A
...	...	...	...	...

ℹ️ Only the first 20 benchmarks are displayed. Go to the app to view all benchmarks.

[camchenry]

I think the additional dependency is okay personally. It's not too surprising to me that the AST depends on data structures, especially custom ones. We can always turn them into separate crates (or features like you say) later.

[graphite-app]

Merge activity

• Mar 4, 9:04 PM EST: A user added this pull request to the Graphite merge queue.
• Mar 4, 9:44 PM EST: A user merged this pull request with the Graphite merge queue.