ADR-0012: oxc_parser and oxc_resolver for TypeScript and JavaScript

• Status: Accepted
• Date: 2026-09-20
• Derives from: design.md § The five stages (stage 2), § What each extractor has to get right (TypeScript), § Language decision; dependency-cruiser coverage § Extraction and resolution, § Options (parser, enhancedResolveOptions, tsConfig)
• Constrains: architecture.md § Extractors
• Implemented by: Wave 0 plan, Wave 1 plan

Context

dependency-cruiser resolves with enhanced-resolve and parses with acorn, swc or tsc. oxc_resolver is the Rust port of enhanced-resolve, so exportsFields, conditionNames, mainFields, aliasFields, tsconfig paths / baseUrl / extends / references, symlinks and Yarn PnP carry over by construction. oxc_parser handles JS, TS, JSX, TSX, decorators and stage-3 syntax in well under a millisecond per file.

Decision

• rb-extract-ts parses with oxc_parser and resolves with oxc_resolver. Both are MIT.
• The parser option (acorn / swc / tsc) is accepted, satisfied by oxc, and recorded in optionsUsed for the report.
• Every dependency form dependency-cruiser knows is extracted: ES imports and re-exports, import type, import(), require, AMD define and require, exotic require names, import =, triple-slash directives, JSDoc imports (read from the comment table, not by switching parser), process.getBuiltinModule.
• Vue and Svelte single-file components are split to their <script> blocks and then parsed by oxc (wave 2).
• Babel syntax needs no Babel: oxc parses it; only babel-plugin-module-resolver aliases are read from the Babel config. webpack configs are evaluated in the sandbox (ADR-0006) and their resolve block read.
• enhancedResolveOptions.cachedInputFileSystem.cacheDuration is accepted and ignored; the resolver caches per run.
• CoffeeScript and LiveScript are not parsed natively (ADR-0017).

Consequences

• Parity is measured against dependency-cruiser's 546 extraction fixtures (ADR-0009); the extractor is done when they produce the same edges.
• oxc and oxc_resolver are pinned in Cargo.toml and bumped through a pull request that re-runs gate 1.

Alternatives considered

• swc. A larger dependency, and its resolver is not enhanced-resolve's.
• tree-sitter. No resolver; would leave the whole of enhanced-resolve to reimplement.