perf(linter/plugins): add fast path for files with no comments

[overlookmotel]

Optimization to comments deserialization. Files which have no comments are probably fairly common. Add a fast path for this case. We have to branch on length === 0 later on anyway, so might as well branch earlier and exit.

[overlookmotel]

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• perf(linter/plugins): add fast path for files with no comments #20366 👈 (View in Graphite)
• fix(linter/plugins): remove hashbang property from AST #20365
• perf(linter/plugins): deserialize comments without AST #20364
• refactor(linter/plugins): move comments methods into own file #20363
• perf(linter/plugins): recycle comment objects #20362
• refactor(ast_tools): remove COMMENTS variant modifier from raw transfer codegen #20361
• main

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[Copilot]

Pull request overview

Adds a performance optimization in the oxlint JS plugin layer by short-circuiting comment initialization for files that contain zero comments, reducing work in a common case.

Changes:

• Add a shared frozen empty comments array and return early from initComments() when commentsLen === 0.
• Minor refactor/simplification of a string replacement in the TypeScript type generator.

Reviewed changes

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

File	Description
apps/oxlint/src-js/plugins/comments.ts	Introduces the no-comments fast path and shared empty comments array.
tasks/ast_tools/src/generators/typescript.rs	Collapses a multi-line replacen call into a single line.

[Copilot]

Pull request overview

Adds a fast-path in the JS-side comment deserialization to avoid work for files with zero comments (a common case), while preserving the existing initComments() contract that sourceText is initialized after initialization.

Changes:

• Add a shared, reusable empty comments array and early-return in initComments() when commentsLen === 0.
• Minor tweak to hashbang/shebang detection logic during comment initialization.
• Update oxlint NAPI bindings exports/types (notably removing Severity and several type declarations).

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

File	Description
apps/oxlint/src-js/plugins/comments.ts	Adds an early-exit fast path for commentless files and reuses a shared empty comments array.
apps/oxlint/src-js/bindings.js	Stops exporting Severity from the JS bindings surface.
apps/oxlint/src-js/bindings.d.ts	Removes Severity and other previously exported interfaces from the generated TS declarations.

Comments suppressed due to low confidence (1)

apps/oxlint/src-js/bindings.js:586

• This PR is described as a comments deserialization perf-only change, but this hunk stops exporting Severity from the oxlint JS bindings. If this export is still part of the expected bindings surface (consistent with other NAPI packages in this repo like napi/parser and apps/oxfmt), this is a breaking change and should either be reverted or called out explicitly (and versioned accordingly).

const { applyFixes, getBufferOffset, lint, parseRawSync, rawTransferSupported } = nativeBinding
export { applyFixes }
export { getBufferOffset }
export { lint }
export { parseRawSync }