jscpd

Copy-paste detector for JavaScript, TypeScript, and many other languages.

Quick Start

# With ignore patterns
bunx jscpd --ignore "**/node_modules/**,**/dist/**" <path>

Common Options

| Option | Description | | ------------------ | ---------------------------------------- | | --min-tokens N | Minimum tokens for duplicate detection | | --min-lines N | Minimum lines for duplicate detection | | --threshold N | Fail if duplication % exceeds threshold | | --ignore "glob" | Ignore patterns (comma-separated) | | --reporters type | Output format: console, json, html | | --output path | Output directory for reports | | --silent | Suppress console output |

Workflow

1. Run jscpd to find duplicates
2. Review the reported duplicates
3. Refactor to eliminate duplication
4. Re-run to verify cleanup

Related Skills

• maintenance: Refactoring and technical debt management
• design: DRY principle violations
• ast-grep: Structural refactoring of duplicated patterns