eslint-deprecation-counter

A CLI tool to detect and count deprecated API usage in your TypeScript and JavaScript projects using ESLint.

Features

• Detects deprecated code in .ts, .tsx, .js, and .jsx files.
• Customizable file patterns and ignore patterns.
• Outputs a JSON summary of deprecation counts.
• Supports TypeScript type-level deprecation detection.

Installation

Run directly using npx:

npx eslint-deprecation-counter

Usage

Run the command in your project's root directory:

npx eslint-deprecation-counter

Environment Variables

• LINT_FILES: Override the default file pattern (./**/*.{ts,tsx}) to specify files to lint.

  Example:

  LINT_FILES='./src/**/*.{js,ts,tsx}' npx eslint-deprecation-counter

• IGNORE_PATTERNS: Customize ignore patterns (comma-separated). Defaults to "**/node_modules/**,.git/**".

  Example:

  IGNORE_PATTERNS="**/dist/**,**/build/**" npx eslint-deprecation-counter

• CI: When set, optimizes ESLint's caching strategy for CI environments.

TypeScript Support

To detect deprecations in TypeScript declaration files (.d.ts) and type-level deprecations, ensure you have a tsconfig.json file in your project's root.

Example Output

{
  "'oldFunction' is deprecated.": 3,
  "'legacyAPI' is deprecated.": 1
}