ESLint Config iPlayer

10.0.1 verified Sat Apr 25 auth: no javascript

ESLint configuration for BBC iPlayer projects. Version 10.0.1 requires ESLint 9 and uses FlatConfig (eslint.config.js) instead of the legacy .eslintrc format. Provides presets: base, js, jsx, ts, tsx, legacy. Peer dependencies include eslint >=9.0.0 and typescript >=4.0.0. Breaking change from v9 to v10: switch to FlatConfig; old package.json extends no longer work. Release cadence follows BBC iPlayer needs.

Common errors

error Configuration for rule "no-console" is invalid ↓

cause FlatConfig does not accept legacy rule config format (e.g., array).

fix

Use object format for rule options. Check each rule's schema.

error Cannot find module 'eslint-config-iplayer' ↓

cause Missing peer dependency or wrong extends name without full package name.

fix

Ensure eslint-config-iplayer is installed and use full name in FlatCompat.extends.

Warnings

breaking Version 10 drops support for .eslintrc files and package.json eslintConfig. Must use eslint.config.js with FlatCompat. ↓

fix Switch to FlatConfig as shown in quickstart.

deprecated Legacy extends 'iplayer/base' etc. from .eslintrc are deprecated. Use FlatCompat instead. ↓

fix Use eslint.config.js with FlatCompat.extends('eslint-config-iplayer/base').

gotcha Full package name required in compat.extends: e.g., 'eslint-config-iplayer/tsx' not 'iplayer/tsx'. ↓

fix Always prefix with 'eslint-config-iplayer/'.

Install

npm install eslint-config-iplayer

yarn add eslint-config-iplayer

pnpm add eslint-config-iplayer

Imports

flat config with compat

wrong

module.exports = { extends: 'iplayer/tsx' }

correct

const compat = new (require('@eslint/eslintrc').FlatCompat)({ baseDirectory: __dirname }); module.exports = [ { ignores: ['node_modules'] }, ...compat.extends('eslint-config-iplayer/tsx') ];

v10 uses ESLint 9 FlatConfig; require('@eslint/eslintrc').FlatCompat is needed to extend. Old object format breaks.

import in ESM

wrong

import config from 'eslint-config-iplayer'

correct

import { FlatCompat } from '@eslint/eslintrc'; const compat = new FlatCompat({ baseDirectory: import.meta.url });

Package is not ESM; use FlatCompat with import.meta.url in ESM projects.

presets js/jsx/ts/tsx/base/legacy
wrong
```
compat.extends('iplayer')
```
correct
```
compat.extends('eslint-config-iplayer/tsx')
```
scoped extends require full package name.

Quickstart

Shows how to set up ESLint 9 FlatConfig with eslint-config-iplayer v10 using FlatCompat for TypeScript+JSX.

// Install
npm install --save-dev eslint eslint-config-iplayer @eslint/eslintrc

// eslint.config.js
const { FlatCompat } = require('@eslint/eslintrc');
const path = require('path');
const compat = new FlatCompat({
  baseDirectory: __dirname
});
module.exports = [
  {
    ignores: ['node_modules', 'dist']
  },
  ...compat.extends('eslint-config-iplayer/tsx')
];