perf(napi/parser, linter/plugins): faster deserialization of raw fields

[overlookmotel]

raw field of NumericLiteral, StringLiteral, BigIntLiteral, RegExpLiteral, and JSXText are slices of source text.

So in raw transfer deserializer, skip going through deserializeStr, which can be slow when source contains any non-ASCII characters. Instead just slice the string from the source text directly with sourceText.slice(start, end).

String decoding is the slowest part of raw transfer, so this should be a significant speed gain.

[overlookmotel]

• refactor(ast): simplify ESTree serialization of Ident #20932
• fix(ast_tools): correct error message and doc comment #20930
• refactor(napi/parser, linter/plugins): shorten raw transfer deserializers for Options #20924
• perf(napi/parser, linter/plugins): faster deserialization of raw fields #20923 👈 (View in Graphite)
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 48 untouched benchmarks
⏩ 8 skipped benchmarks¹

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_{Comparing om/04-01-perf_napi_parser_linter_plugins_faster_deserialization_of_raw_fields (0503a78) with main (f9ef1bd)²}

Footnotes

1. 8 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. ↩

2. No successful run was found on main (0503a78) during the generation of this report, so f9ef1bd was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Copilot]

Pull request overview

This PR speeds up JS-side raw-transfer deserialization for raw fields by avoiding string decoding and instead deriving raw directly from the already-available sourceText using span offsets.

Changes:

• Add #[estree(from_span)] attribute support in ast_tools schema + derive parsing.
• Update raw-transfer JS deserializer generation to emit sourceText.slice(start, end) for eligible fields and to inline Option-None checks.
• Apply #[estree(from_span)] to relevant AST node raw fields and regenerate parser/oxlint deserializers accordingly.

Reviewed changes

Copilot reviewed 5 out of 14 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tasks/ast_tools/src/schema/extensions/estree.rs	Adds from_span flag to ESTree field config (docs currently need alignment with implementation).
tasks/ast_tools/src/derives/estree.rs	Parses #[estree(from_span)] on struct fields into schema metadata.
tasks/ast_tools/src/generators/raw_transfer.rs	Emits sourceText.slice(start, end) and refactors Option-None detection helper (needs an additional validation guard).
crates/oxc_ast/src/ast/literal.rs	Marks raw on several literals as from_span so JS deserializer can slice directly from source.
crates/oxc_ast/src/ast/jsx.rs	Marks JSXText.raw as from_span.
napi/parser/src-js/generated/deserialize/*.js	Regenerated parser deserializers now compute raw via sourceText.slice(start, end).
apps/oxlint/src-js/generated/deserialize.js	Regenerated oxlint deserializer now computes raw via sourceText.slice(start, end).

[graphite-app]

Merge activity

• Apr 1, 12:05 PM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Apr 1, 12:12 PM UTC: Merged by the Graphite merge queue.