Files
oxc-guard 5a6e37e5cf release(crates): oxc v0.150.0 (#26632)
### 🚀 Features

- ca649e0 ecma: Define math constants as known globals and resolve their types (#26585) (Armano)
- 9ef028c codegen: Add `ascii_only` option (#25994) (Samuel Attard)
- 80a76a0 minifier: Negate binary comparison for `typeof x < 'u'` (#26367) (Armano)

### 🐛 Bug Fixes

- 8ca76da parser: Reject `accessor` modifiers on methods (#26617) (camc314)
- 1916f31 parser: Reject `readonly` modifier on constructors (#26612) (camc314)
- 1c42008 parser: Handle escaped let in for loops (#26583) (camc314)
- d21d5cf parser: Recognize annotated empty arrows in conditionals (#26537) (camc314)
- d7713ad parser: Classify Unicode line breaks in block comments (#26536) (camc314)
- 75cd919 transformer: Preserve receivers in private optional chains (#26535) (camc314)
- b32d25d parser: Reject escaped import-phase keywords (#26534) (camc314)
- 47b8311 parser: Recognize contextual binding names in type lookaheads (#26532) (camc314)
- d6b6705 parser: Require arrow separator in TypeScript function types (#26529) (camc314)
- e98beef parser: Disambiguate await using in for initializers (#26527) (camc314)
- 92afee6 parser: Allow parenthesized JSX comma expressions with preserve_parens=false (#26524) (camc314)
- 31508b1 parser: Reject return types on constructor overloads (#26523) (camc314)
- a091fc4 parser: Validate await context for await using declarations (#26495) (camc314)
- 5501e86 parser: Disallow in expressions in using for-loop initializers (#26490) (camc314)
- c8e5fa7 parser: Allow escaped type names in import and export specifiers (#26487) (camc314)
- 2dcee2f parser: Reject async modifiers on class fields (#26486) (camc314)
- 973d58e parser: Require comma after TypeScript this parameter (#26480) (camc314)
- 32d00c5 codegen: Preserve instantiation expression precedence (#26424) (camc314)
- cfa47ab parser: Allow `in` expressions in class static blocks (#26423) (camc314)
- 5986187 packages/codegen: Preserve private-in right operand precedence (#26420) (camc314)
- f8e6c6c packages/codegen: Preserve in restriction through yield arguments (#26421) (camc314)
- d61e3bf parser: Validate TS named tuple rest elements (#26419) (camc314)
- ae6c386 codegen: Preserve in restriction through yield arguments (#26413) (camc314)
- 42ac916 codegen: Preserve private-in right operand precedence (#26411) (camc314)
- 10521b2 parser: Allow escaped type default import bindings (#26409) (camc314)
- 72cb5e3 parser: Reject rest parameters in getters (#26400) (camc314)
- 6e15ad5 packages/codegen: Print matching quoted import names as identifiers (#26404) (camc314)
- bbbb4bc packages/codegen: Preserve private-in left operand precedence (#26403) (camc314)
- a111b5b packages/codegen: Print accessibility modifiers before abstract (#26402) (camc314)
- 4e76602 parser: Allow `in` in arrow block bodies within `for` initializers (#26395) (camc314)
- b20fc19 parser: Reject partially parenthesized mixed coalesce expressions (#26394) (camc314)

###  Performance

- 1f902a6 isolated_declarations: Key scope maps by `Ident` (#26380) (Dunqing)
- a242469 minfiier: Reduce allocs when creating indirect access (#26601) (Armano)
- 5b4787f minifier: Update chain expressions in place (#26544) (Armano)
- 0bc1661 minifier: Try merging before creating new expression statements (#26556) (Armano)
- c78d707 minifier: Process newly created stmt in handle_if_statement (#26541) (Armano)
- 029c84b minfier: Update expressions in place when substituting alternate syntax (#26460) (Armano)
- d198982 codegen: Outline postfix source mapping work (#26450) (camc314)
- 53f006e ecmascript: Format small integer literals with itoa (#26446) (camc314)
- 8bfb8c0 codegen: Avoid duplicate sourcemap name lookups (#26441) (camc314)

### 📚 Documentation

- 38533ac ast: Move type annotation span comment to span field (#26522) (camc314)
2026-09-14 11:25:40 +00:00
..

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.