eslint-plugin-require-js-extension

TypeScript doesn't transform extensions and doesn't enforce file extensions.

This is a simple eslint plugin that ensures that relative imports and exports have .js extensions.

Credit for the original implementation goes to johnrees. ❤️

1. Install

npm install --save-dev eslint-plugin-require-js-extension

2. Create eslint.config.js

import eslintPluginRequireJsExtension from 'eslint-plugin-require-js-extension'

export default [
  {
    plugins: {
      'require-js-extension': eslintPluginRequireJsExtension,
    },
    rules: {
      'require-js-extension/require-js-extension': 'error',
      'require-js-extension/require-index': 'error',
    },
  },
]

Alternatively, use the recommended config:

import eslintPluginRequireJsExtension from 'eslint-plugin-require-js-extension'

export default [
  {
    plugins: {
      'require-js-extension': eslintPluginRequireJsExtension,
    },
    extends: ['eslintPluginRequireJsExtension/recommended'],
  },
]

3. Code

// source.js

import Target from './target'

4. Lint

eslint .

source.js
  1:1  error  Relative imports and exports must end with .js  require-js-extension/require-js-extension

5. Fix

eslint --fix .

// source.js

import Target from './target.js'