Migration

ESLint deprecated of their formatting rules in v8.53.0 and recommended users to migrate to ESLint Stylistic. While ESLint never removes deprecated rules, it still means that deprecated rules will not receive any future updates. In ESLint Stylistic, we already migrated all those rules and will continue to maintain them.

This guide will help you to do the migration.

Manual Migrate

ESLint Stylistic is migrated from 3 different sources packages:

• eslint -> @stylistic/eslint-plugin-js
  • Built-in stylistic rules for JavaScript
• @typescript-eslint/eslint-plugin -> @stylistic/eslint-plugin-ts
  • Stylistic rules for TypeScript
• eslint-plugin-react -> @stylistic/eslint-plugin-jsx
  • Framework-agnostic JSX rules

There are two ways to migrate your project to ESLint Stylistic:

• Approach 1: Migrate to Single Plugin: One single package for JavaScript, TypeScript and JSX. This is the recommended way.
• Approach 2: Migrate to 1-to-1 Plugins: One package for each source package. Rules are 1:1 mapped, and would be easier to migrate.

Approach 1: Migrate to Single Plugin

To make the rules configuration easier, we merged all three plugins into one single plugin.

npm i -D @stylistic/eslint-plugin

// .eslintrc.js
module.exports = {
  plugins: [
    '@stylistic'
  ],
  rules: {
    // ESLint built-in stylistic rules:
    // Add `@stylistic/` prefix
    'semi': 'error',
    '@stylistic/semi': 'error',

    // `@typescript-eslint` rules:
    // Change `@typescript-eslint/` to `@stylistic/` prefix
    '@typescript-eslint/semi': 'error',
    '@stylistic/semi': 'error',

    // `eslint-plugin-react` rules:
    // Change `react/` to `@stylistic/` prefix
    'react/jsx-indent': 'error',
    '@stylistic/jsx-indent': 'error',
  }
}

And usually typescript-eslint would ask you to disable the built-in rules, in favor of the @typescript-eslint version. With ESLint Stylistic, you only need one rule to handle both JavaScript and TypeScript:

// .eslintrc.js

module.exports = {
  plugins: [
    '@stylistic'
  ],
  rules: {
    // Previously, you need to disable the built-in rule
    'semi': 'off',
    '@typescript-eslint/semi': 'error',

    // Now only need one rule
    '@stylistic/semi': 'error',
  }
}

Approach 2: Migrate to 1-to-1 Plugins

To make the migration easier, we also provide a 1-to-1 mapping for each source package's plugins. Unlike the single plugin approach, you need to install 3 different packages with additional prefixes in the rules.

ESLint Code (JavaScript)

npm i -D @stylistic/eslint-plugin-js

// .eslintrc.js
module.exports = {
  plugins: [
    '@stylistic/js'
  ],
  rules: {
    // ESLint built-in stylistic rules:
    // Add `@stylistic/js/` prefix
    'semi': 'error',
    '@stylistic/js/semi': 'error',
  }
}

TypeScript

npm i -D @stylistic/eslint-plugin-ts

// .eslintrc.js
module.exports = {
  plugins: [
    '@stylistic/ts'
  ],
  rules: {
    // `@typescript-eslint` rules:
    // Change `@typescript-eslint/` to `@stylistic/ts/` prefix
    '@typescript-eslint/semi': 'error',
    '@stylistic/ts/semi': 'error',
  }
}

JSX

npm i -D @stylistic/eslint-plugin-jsx

// .eslintrc.js
module.exports = {
  plugins: [
    '@stylistic/jsx'
  ],
  rules: {
    // `eslint-plugin-react` rules:
    // Change `react/` to `@stylistic/jsx/` prefix
    'react/jsx-indent': 'error',
    '@stylistic/jsx/jsx-indent': 'error',
  }
}

ESLint Migrate Plugin

We provide an ESLint plugin for migrating built-in stylistic rules to the @stylistic namespace.

npm i -D @stylistic/eslint-plugin-migrate

// .eslintrc.js
module.exports = {
  plugins: [
    '@stylistic/migrate'
  ],
}

And opt-in to your eslint configure file by adding eslint comments to the top of your file:

// Migrate built-in rules to @stylistic/js namespace
/* eslint @stylistic/migrate/migrate-js: "error" */

// Migrate `@typescript-eslint` rules to @stylistic/ts namespace
/* eslint @stylistic/migrate/migrate-ts: "error" */

module.exports = {
  rules: {
    indent: ['error', 2], // Error: Use @stylistic/js/indent instead

    '@typescript-eslint/indent': ['error', 2], // Error: Use @stylistic/ts/indent instead
  }
}

Disable Legacy Rules

In cases that you are extending some presets that still include legacy rules and haven't migrated, we provide configuration presets to disable them all.

Legacy Config

// .eslintrc.js
module.exports = {
  extends: [
    'eslint:recommended',
    'plugin:@typescript-eslint/recommended',
    // ...
    'plugin:@stylistic/disable-legacy',
  ],
  plugins: [
    '@stylistic'
  ],
  rules: {
    '@stylistic/semi': 'error',
    // ...
  }
}

Flat Config

// eslint.config.js
import { FlatCompat } from '@eslint/eslintrc'
import StylisticPlugin from '@stylistic/eslint-plugin'

const compat = new FlatCompat()

export default [
  // `extends` is not supported in flat config, can you use `@eslint/eslintrc` to handle it
  ...compat({
     extends: [
      'eslint:recommended',
      'plugin:@typescript-eslint/recommended',
      // ...
    ],
  }),
  // override the legacy rules
  StylisticPlugin.configs['disable-legacy'],
  // your own rules
  {
    plugins: {
      stylistic: StylisticPlugin
    },
    rules: {
      'stylistic/semi': 'error',
      // ...
    }
  }
]

Packages Metadata

If you want to handle the migration on your own, we also expose the metadata for easier programmatic usage.

npm i -D @eslint-stylistic/metadata

import { rules, packages } from '@eslint-stylistic/metadata'

console.log(rules)