Files
oxc-guard 0389c4010e release(crates): oxc v0.146.0 (#25912)
### 🚀 Features

- 83cb516 minifier: Improve negation of expressions in boolean context (#25755) (Armano)

### 🐛 Bug Fixes

- 134fb22 isolated-declarations: Preserve unresolved parameter types (#25909) (Dunqing)
- 526c2b3 codegen: Remove deprecated test APIs (#25889) (camc314)
- 344a9b2 codegen: Align enum template sourcemaps (#25872) (camc314)

### ⚡ Performance

- 5ef0c93 minifier: Unwrap all unary exprs without creating dummy expressions (#25891) (Armano)
- 8783524 packages/codegen: Remove loop from `growMappingBuffer` (#25886) (overlookmotel)
- b6b14c0 packages/codegen: Remove redundant branch (#25885) (overlookmotel)
- be6adf0 packages/sourcemap: Make `location` passed to `recordSourceMapping` always a number (#25884) (overlookmotel)
- f720f15 packages/codegen: Take named-mapping only code off hot path in `recordSourceMapping` (#25883) (overlookmotel)
- a734af5 packages/codegen: Remove redundant setting of `last` in `printImportAttributes` and `printIf` (#25882) (overlookmotel)
- c6e44c6 packages/codegen: Combine 2 writes in `printJSXElement` (#25881) (overlookmotel)
- 8801662 packages/codegen: Remove redundant mapping from `printParams` (#25880) (overlookmotel)

### 📚 Documentation

- 5ad330e packages/codegen: Reformat comments (#25876) (overlookmotel)
2026-08-19 08:29:51 +00:00
..

Oxc Span

Source position utilities and span management for precise error reporting.

Overview

This crate provides essential utilities for managing source positions and spans in JavaScript and TypeScript code. It enables precise error reporting, source mapping, and location-aware transformations across all oxc tools.

Key Features

  • Precise positions: Accurate byte-level source positions
  • Span utilities: Source ranges with start and end positions
  • Source type detection: Automatic language and module detection
  • Content comparison: Semantic equality for AST nodes

Architecture

Span System

  • Byte positions: All positions are UTF-8 byte offsets
  • Inclusive ranges: Spans include start position, exclude end position
  • Efficiency: Uses u32 for positions, supporting files up to 4GB
  • Precision: Enables precise error highlighting and source maps

Source Type System

The source type encodes important metadata:

  • Language: JavaScript vs TypeScript
  • Module system: ESM vs Script
  • JSX support: JSX vs plain syntax
  • Variant: Standard vs definition files (.d.ts)

Integration Points

  • Parser: Creates spans during tokenization and parsing
  • Semantic: Tracks spans for all symbols and references
  • Linter: Uses spans for precise error reporting
  • Codegen: Maintains spans for source map generation
  • Transformer: Preserves spans during AST manipulation

This crate provides the foundation for precise source location tracking throughout the oxc toolchain.