chore(sveltekit): replace recast + @babel/parser with acorn#19533
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roli-lpci wants to merge 1 commit intogetsentry:developfrom
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chore(sveltekit): replace recast + @babel/parser with acorn#19533roli-lpci wants to merge 1 commit intogetsentry:developfrom
roli-lpci wants to merge 1 commit intogetsentry:developfrom
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Replaces recast and @babel/parser with acorn and @sveltejs/acorn-typescript for AST parsing in the auto-instrumentation plugin. Since the code only reads the AST (never transforms or prints), the full recast pipeline is unnecessary. Key changes: - Delete recastTypescriptParser.ts (no longer needed) - Use acorn Parser.extend(tsPlugin()) for TypeScript parsing - Use @sveltejs/acorn-typescript (actively maintained) instead of TyrealHu's abandoned acorn-typescript - Fix StringLiteral -> Literal node type check (ESTree compliance) - Fix ast.program -> ast (acorn returns Program directly) - Use try/catch for parse errors instead of null program check Removes ~8 transitive dependencies (recast, ast-types, esprima, source-map, tslib, tiny-invariant, @babel/parser, @babel/types). Ref: getsentry#19447 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Replaces
recastand@babel/parserwithacornand@sveltejs/acorn-typescriptfor AST parsing in the sveltekit auto-instrumentation plugin.yarn lint) & (yarn test).Ref #19447
What this does
The
autoInstrumentVite plugin parses SvelteKit+page.ts/+layout.server.tsfiles to detectexport const loadorexport function loaddeclarations. It only reads the AST — never transforms or prints it — so recast's source-preserving round-trip feature is entirely unused.This replaces the full recast + @babel/parser pipeline with acorn (Node.js's own parser) and
@sveltejs/acorn-typescript(the actively maintained TypeScript plugin used by SvelteKit itself).Changes
recastTypescriptParser.ts— the 91-line Babel parser config with 20+ plugin declarations is no longer neededrecast.parse()withacorn.Parser.extend(tsPlugin()).parse()inautoInstrument.tsStringLiteral(Babel-specific) →Literal(ESTree standard) for string literal export detectionast.program(recast's File wrapper) → directast(acorn returns Program)try/catcharound parse (acorn throws SyntaxError) replaces dubious null check(specifier.exported as unknown as t.StringLiteral)in favor of proper discriminant narrowingDependency reduction
Removed:
recast,ast-types,esprima,source-map,tslib,tiny-invariant,@babel/parser,@babel/types,@babel/helper-string-parser,@babel/helper-validator-identifierAdded:
acorn(already in dep tree via Vite/Rollup),@sveltejs/acorn-typescript(already in dep tree via@sveltejs/kit)Net effect: ~8 fewer transitive dependencies, zero new packages for end users.
Why @sveltejs/acorn-typescript?
The original
acorn-typescriptpackage by TyrealHu hasn't been updated since January 2024 and has known unpatched bugs. The Svelte team's fork (@sveltejs/acorn-typescript) is actively maintained and is already a transitive dependency of every SvelteKit project.All 69 existing tests pass without modification.
Co-Authored-By: Claude Opus 4.6 noreply@anthropic.com