[](https://travis-ci.com/mdx-js/eslint-mdx) [](https://www.codacy.com/app/JounQin/eslint-mdx) [](https://codecov.io/gh/mdx-js/eslint-mdx) [](https://github.com/plantain-00/type-coverage) [](https://github.com/mdx-js/eslint-mdx/releases) [](https://david-dm.org/mdx-js/eslint-mdx?type=dev) [](https://conventionalcommits.org) [](https://github.com/prettier/prettier) [](https://lerna.js.org) [](https://codechecks.io) > [ESLint][] Parser/Plugin for [MDX][], helps you lint all ES syntaxes. > Linting `code` blocks can be enabled with `mdx/code-blocks` setting too! > Work perfectly with `eslint-plugin-import`, `eslint-plugin-prettier` or any other eslint plugins. > And also can be integrated with [remark-lint][] plugins to lint markdown syntaxes. ## TOC - [VSCode Extension](#vscode-extension) - [Packages](#packages) - [Install](#install) - [Usage](#usage) - [Parser Options](#parser-options) - [Rules](#rules) - [mdx/no-jsx-html-comments](#mdxno-jsx-html-comments) - [mdx/no-unused-expressions](#mdxno-unused-expressions) - [mdx/remark](#mdxremark) - [Prettier Integration](#prettier-integration) - [Changelog](#changelog) - [License](#license) ## VSCode Extension [](https://marketplace.visualstudio.com/items?itemName=JounQin.vscode-mdx) [VSCode MDX][]\: Integrates with [VSCode ESLint][], syntaxes highlighting and error reporting. ## Packages This repository is a monorepo managed by [Lerna][] what means we actually publish several packages to npm from same codebase, including: | Package | Description | Version | Peer Dependencies | Dependencies | | -------------------------------------------------- | ---------------------------------------------- | ------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [`eslint-mdx`](/packages/eslint-mdx) | ESLint Parser for MDX | [](https://www.npmjs.com/package/eslint-mdx) | [](https://david-dm.org/mdx-js/eslint-mdx?path=packages/eslint-mdx&type=peer) | [](https://david-dm.org/mdx-js/eslint-mdx?path=packages/eslint-mdx) | | [`eslint-plugin-mdx`](/packages/eslint-plugin-mdx) | ESLint Plugin, Configuration and Rules for MDX | [](https://www.npmjs.com/package/eslint-plugin-mdx) | [](https://david-dm.org/mdx-js/eslint-mdx?path=packages/eslint-plugin-mdx&type=peer) | [](https://david-dm.org/mdx-js/eslint-mdx?path=packages/eslint-plugin-mdx) | ## Install ```sh # yarn yarn add -D eslint-plugin-mdx # npm npm i -D eslint-plugin-mdx ``` ## Usage 1. In your ESLint config file: 1. If you're using `eslint >= 6.4.0`, just add: ```jsonc { "extends": ["plugin:mdx/recommended"], // optional, if you want to lint code blocks at the same time "settings": { "mdx/code-blocks": true } } ``` 2. If you're using `eslint >=6.0.0 and <6.4.0`, add as following because it does not support overrides from npm pkg: ```jsonc { "extends": ["plugin:mdx/recommended"], // optional, if you want to lint code blocks at the same time "settings": { "mdx/code-blocks": true }, "overrides": [ { "files": ["*.md"], "rules": { "prettier/prettier": [ 2, { // unnecessary if you're not using `eslint-plugin-prettier`, but required if you are "parser": "markdown" } ] } }, { "files": ["*.mdx"], "extends": ["plugin:mdx/overrides"] }, { "files": "**/*.{md,mdx}/**", "extends": "plugin:mdx/code-blocks" } ] } ``` 3. If you're using `eslint@^5.0.0`, you need to enable this parser/plugin manually, because `eslint@5` does not support `extends` for `overrides` property in its configuration: ```js const { configs } = require('eslint-plugin-mdx') module.exports = { extends: ['plugin:mdx/recommended'], // optional, if you want to lint code blocks at the same time settings: { 'mdx/code-blocks': true, }, overrides: [ { files: ['*.md'], rules: { 'prettier/prettier': [ 2, { // unnecessary if you're not using `eslint-plugin-prettier`, but required if you are parser: 'markdown', }, ], }, }, { files: ['*.mdx'], ...configs.overrides, }, { files: '**/*.{md,mdx}/**', ...configs.codeBlocks, }, ], } ``` 2. Make sure ESLint knows to run on `.md` or `.mdx` files: ```sh eslint . --ext js,md,mdx ``` ## Parser Options 1. `parser` (`string | ParserConfig | ParserFn`): Custom parser for ES syntax is supported, although `@typescript-eslint/parser` or `@babel/eslint-parser` or `babel-eslint` will be detected automatically what means you actually do not need to do this: ```json { "extends": ["plugin:mdx/recommended"], "parserOptions": { "parser": "babel-eslint" } } ``` 2. `extensions` (`string | string[]`): `eslint-mdx` will only resolve `.mdx` files by default, files with other extensions will be resolved by the `parser` option. If you want to resolve other extensions as like `.mdx`, you can use this option. 3. `markdownExtensions` (`string | string[]`): `eslint-mdx` will only treat `.md` files as plain markdown by default, and will lint them via remark plugins. If you want to resolve other extensions as like `.md`, you can use this option. ## Rules ### mdx/no-jsx-html-comments _Fixable_: HTML style comments in jsx block is invalid, this rule will help you to fix it by transforming it to JSX style comments. ### mdx/no-unused-expressions [MDX][] can render `jsx` block automatically without exporting them, but [ESLint][] will report `no-unused-expressions` issue which could be unexpected, this rule is the replacement, so make sure that you've turned off the original `no-unused-expressions` rule. ### mdx/remark _possible fixable depends on your remark plugins_: Integration with [remark-lint][] plugins, it will read [remark's configuration](https://github.com/remarkjs/remark/tree/master/packages/remark-cli#remark-cli) automatically via [cosmiconfig][]. But `.remarkignore` will not be respected, you should use `.eslintignore` instead. If you want to disable or change severity of some related rules, it won't work by setting rules in eslint config like `'remark-lint-no-duplicate-headings': 0`, you should change your remark config instead like following: ```jsonc { "plugins": [ "@1stg/remark-config", // change to error severity, notice `[]` is required ["lint-no-duplicate-headings", [2]], // disable following plugin [ "lint-no-multiple-toplevel-headings", [0] // or false ] ] } ``` ## Prettier Integration If you're using [remark-lint][] feature with [Prettier][] both together, you can try [remark-preset-prettier][] which helps you to _turn off all rules that are unnecessary or might conflict with [Prettier][]_. ```json { "plugins": [ "preset-lint-consistent", "preset-lint-recommended", "preset-lint-markdown-style-guide", "preset-prettier" ] } ``` ## Changelog Detailed changes for each release are documented in [CHANGELOG.md](./CHANGELOG.md). ## License [MIT][] © [JounQin][]@[1stG.me][] [1stg.me]: https://www.1stg.me [cosmiconfig]: https://github.com/davidtheclark/cosmiconfig [eslint]: https://eslint.org [eslint-plugin-react]: https://github.com/yannickcr/eslint-plugin-react [jounqin]: https://GitHub.com/JounQin [lerna]: https://github.com/lerna/lerna [mdx]: https://github.com/mdx-js/mdx [mit]: http://opensource.org/licenses/MIT [prettier]: https://prettier.io [remark-lint]: https://github.com/remarkjs/remark-lint [remark-preset-prettier]: https://github.com/JounQin/remark-preset-prettier [vscode eslint]: https://marketplace.visualstudio.com/items?itemName=dbaeumer.vscode-eslint [vscode mdx]: https://github.com/mdx-js/vscode-mdx