Files
oxc-guard 60fa13878c release(crates): oxc v0.149.0 (#26397)
### 💥 BREAKING CHANGES

- 66744f0 parser: [**BREAKING**] Rename `panicked` to `fatal_error` in `ParserReturn` (#26382) (overlookmotel)
- 2c9a947 parser: [**BREAKING**] Reduce `MAX_LEN` to 256 bytes below `u32::MAX` (#26352) (overlookmotel)

### 🚀 Features

- 32bdc5b allocator: Construct `ArenaHashSet` with any `Default` hasher (#26372) (Dunqing)
- a17de58 minifier: Process of return/throw in non last position and fix async * inlining (#26214) (Armano)
- bfb4c57 parser: Distinguish unapplied no-side-effects comments (#26120) (碳苯 Carbon)
- 1d9b9d3 ast: Add `GetNodeId` trait (#26145) (camc314)

### 🐛 Bug Fixes

- b156333 codegen: Order accessibility before abstract on accessors (#26392) (camc314)
- 116c8b8 transformer/class-properties: Keep private methods in class-expression scope (#26308) (Changsu Seong)
- 1400a0f parser: Require a string source after `export ... from` (#26389) (camc314)
- 2da73b7 codegen: Print matching quoted import names as identifiers (#26386) (camc314)
- 0a81d29 codegen: Preserve private-in left operand precedence (#26383) (camc314)
- 9a02337 parser: Correctly round large nondecimal literals (#26379) (camc314)
- 3d95477 transformer: Gate async-only rewrites by owning transform (#26326) (Dunqing)
- f45a9ee transformer: Limit arguments capture to lowered async functions (#26317) (Dunqing)
- 789969f transformer: Gate this capture by owning async transform (#26227) (Dunqing)
- affeb14 minifier: Mangle class private members in Node API (#26118) (碳苯 Carbon)
- 8b35abd semantic: Detect duplicate private class elements (#26361) (camc314)
- 457ed57 semantic: Reject await and yield in rest parameter defaults (#26359) (camc314)
- 4b89c7b semantic: Reject jumps across arrow functions (#26357) (camc314)
- c966aca parser: Do not omit `<` token opening type argument list (#26328) (overlookmotel)
- f07dca5 ast_visit: Add the trimmed prefix length to translation table offsets (#26173) (Bharadwaj Pendyala)
- 3ab9bd1 parser: Do not re-lex template substitution tail after fatal error (#26230) (overlookmotel)
- 07851b9 parser: Fix debug assert failure when lexer error with tokens enabled (#26229) (overlookmotel)
- 00dea7a allocator: Gate `Allocator::data_end_ptr` behind fixed_size feature (#26248) (camc314)
- 853ffab ecmascript: Avoid `charAt` panic on 32-bit (#26244) (camc314)
- 34feccb runtime: Remove stale regenerator exports (#26243) (camc314)

### ⚡ Performance

- 34a242e minifier: Use `Ident` for property mangler (#26334) (sapphi-red)
- 5303f5c minifier: Unify merging of last expression into target sequence (#26264) (Armano)
- 2ca7d29 minifier: Consume nodes in minimize_statements in reverse order (#26258) (Armano)
- d2354b4 mangler: Use `Ident` for variable names to keep (#26333) (sapphi-red)
- 5b3e335 minifier: Use `Ident` instead of `Str` in `KeepVar` (#26332) (sapphi-red)
- 51366fb minifier: Use `IdentHashSet` in `PrivateMemberUsageStack` (#26331) (sapphi-red)
- d19c42a minifier: Merge nested if stmt in place instead of creating dummies (#26351) (Armano)
- 356def6 parser: Shrink annotation comment ranges (#26356) (overlookmotel)
- a5be474 parser: Shave instruction off `parse_jsx_element_name` (#26355) (overlookmotel)
- 9780663 parser: Remove fatal error guard from `parse_jsx_element_name` (#26354) (overlookmotel)
- 766e12f parser: Remove `token` field from `LexerCheckpoint` (#26350) (overlookmotel)

### 📚 Documentation

- d4b4e61 transformer: Document ES2015 target floor (#26378) (Dunqing)
- 67dd054 ast_visit: Correct out-of-date comments on `Utf8ToUtf16` converter (#26285) (overlookmotel)
- a8ed2a7 minifier: Fix stale validation instructions (#26251) (camc314)
2026-09-07 14:29:34 +00:00
..
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Oxc Transformer Plugins

Specialized transformation plugins for common JavaScript and TypeScript patterns.

Overview

This crate provides specific transformation plugins that can be used independently or as part of the broader oxc transformation pipeline. These plugins handle common transformation needs like global variable injection and module format conversion.

Key Features

  • Global variable injection: Add global variables to modules
  • Module runner transforms: Transform modules for different execution environments
  • Global defines replacement: Replace compile-time constants
  • Composable plugins: Use individually or combine multiple plugins

Architecture

Plugin System

Each plugin implements the transformation logic for a specific use case:

  • Focused responsibility: Each plugin handles one type of transformation
  • Traverse integration: Uses oxc's traversal system for efficient AST walking
  • Composable: Multiple plugins can be applied in sequence
  • Context-aware: Access to semantic information when needed

Common Use Cases

Build-time Optimizations

  • Dead code elimination: Remove unreachable code paths
  • Constant folding: Replace compile-time constants
  • Environment variables: Inject environment-specific values

Module System Compatibility

  • Polyfill injection: Add necessary polyfills for target environments
  • Global shimming: Provide Node.js globals in browser environments
  • Format conversion: Transform between module formats

Development Tools

  • Debug injection: Add development-time debugging code
  • Hot module replacement: Support for HMR systems
  • Testing utilities: Inject test-specific globals

Integration Points

These plugins integrate with:

  • oxc_transformer: Core transformation infrastructure
  • oxc_traverse: AST traversal and mutation
  • Build tools: Webpack, Vite, Rollup, and other bundlers
  • CLI tools: Direct usage in command-line transformations

The plugin architecture enables extensible, composable transformations while maintaining high performance through oxc's efficient traversal system.