Configuring ESLint

The @pagopa/eslint-config package provides a shared ESLint configuration for JavaScript and TypeScript projects.

note

Most rules are autofixable - run eslint --fix src to automatically fix formatting and style issues.

Requirements

This ESLint configuration requires ESLint > 9 with flat config files (eslint.config.js or eslint.config.mjs). We do not support older versions of ESLint or classic configuration files (.eslintrc.*).

Features

• Import Organization: Uses the perfectionist plugin for natural import/export sorting, grouping, and object key reordering
• TypeScript Support: Uses typescript-eslint strict and stylistic configurations
• Prettier Integration: Combines ESLint with Prettier for consistent formatting
• Testing Rules: Specialized configuration for Vitest test files
• Code Quality: Enforces complexity limits and modern JavaScript practices

Installation

pnpm add -D eslint @pagopa/eslint-config

Configuration

Create an eslint.config.js file at the root of your project:

// eslint.config.js
import pagopa from "@pagopa/eslint-config";

export default pagopa;

For CommonJS projects, use eslint.config.mjs instead.

Rules

The configuration includes rules for:

• Unused variables and expressions
• Function complexity (maximum 200 lines)
• Equality operators (== vs ===)
• ... many other code quality checks!

For the complete list of rules, see the configuration implementation.

Scripts

Add these scripts to your package.json:

{
  "scripts": {
    "lint": "eslint --fix src",
    "lint:check": "eslint src"
  }
}