@luxass/eslint-config v4.4.0

@luxass/eslint-config

✨ Features

• Based on antfu's ESLint Config with some modifications
• Auto fix for formatting (aimed to be used standalone without Prettier)
• Designed to work with TypeScript, JSX, Vue out-of-box
• Lints also for json, yaml, toml, markdown
• Sorted imports, dangling commas
• Reasonable defaults, best practices, only one-line of config
• Opinionated, but very customizable
• ESLint Flat config, compose easily!
• Using ESLint Stylistic
• Respects .gitignore by default
• Optional React, Svelte, Solid, UnoCSS, Astro support
• Optional formatters support for CSS, HTML, etc.

Usage

npm install -D eslint @luxass/eslint-config

And create a eslint.config.mjs in your project root:

// eslint.config.mjs
import luxass from '@luxass/eslint-config'

export default luxass()

If you still use some configs from the legacy ESLint RC format, you can use the @eslint/eslintrc package to convert them to the flat config.

// eslint.config.mjs
import luxass from '@luxass/eslint-config'
import { FlatCompat } from '@eslint/eslintrc'

const compat = new FlatCompat()

export default luxass(
  {
    ignores: [],
  },

  // Legacy config
  ...compat.config({
    extends: [
      'eslint:recommended',
      // Other extends...
    ],
  })

  // Other flat configs...
)

Note that .eslintignore no longer works in Flat config, see customization for more details.

Add script for package.json

For example:

{
  "scripts": {
    "lint": "eslint .",
    "lint:fix": "eslint . --fix"
  }
}

Setup for Visual Studio Code (with auto-fix)

Install ESLint extension and add the following to your .vscode/settings.json:

// .vscode/settings.json
{
  // will ensure that eslint can use the experimental flat config
  "eslint.experimental.useFlatConfig": true,

  // disable the default formatter
  "prettier.enable": false,
  "editor.formatOnSave": false,

  // auto fix on save
  "editor.codeActionsOnSave": {
    "source.fixAll.eslint": "explicit",
    "source.organizeImports": "never"
  },

  // silent the stylistic rules in you IDE, but still auto fix them
  "eslint.rules.customizations": [
    { "rule": "style/*", "severity": "off" },
    { "rule": "*-indent", "severity": "off" },
    { "rule": "*-spacing", "severity": "off" },
    { "rule": "*-spaces", "severity": "off" },
    { "rule": "*-order", "severity": "off" },
    { "rule": "*-dangle", "severity": "off" },
    { "rule": "*-newline", "severity": "off" },
    { "rule": "*quotes", "severity": "off" },
    { "rule": "*semi", "severity": "off" }
  ],

  // The following is optional.
  // It's better to put under project setting `.vscode/settings.json`
  // to avoid conflicts with working with different eslint configs
  // that does not support all formats.
  "eslint.validate": [
    "javascript",
    "javascriptreact",
    "typescript",
    "typescriptreact",
    "vue",
    "html",
    "markdown",
    "json",
    "jsonc",
    "yaml",
    "toml",
    "gql",
    "graphql"
  ]
}

Customization

Normally you would only need to import the config and export it:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass()

And that's it! Or you can configure each integration individually, for example:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  // Enable stylistic formatting rules
  // stylistic: true,

  // Or customize the stylistic rules
  stylistic: {
    indent: 2, // 4, or 'tab'
    quotes: 'single', // or 'double'
  },

  // TypeScript and Vue are auto-detected, you can also explicitly enable them:
  typescript: true,
  vue: true,

  // Disable jsonc and yaml support
  jsonc: false,
  yaml: false,

  // `.eslintignore` is no longer supported in Flat config, use `ignores` instead
  ignores: [
    '**/fixtures',
    // ...globs
  ]
})

The luxass factory function also accepts any number of arbitrary custom config overrides:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass(
  {
    // Configures for luxass's config
  },

  // From the second arguments they are ESLint Flat Configs
  // you can have multiple configs
  {
    files: ['**/*.ts'],
    rules: {},
  },
  {
    rules: {},
  },
)

Going more advanced, you can also import fine-grained configs and compose them as you wish:

We wouldn't recommend using this style in general unless you know exactly what they are doing, as there are shared options between configs and might need extra care to make them consistent.

// eslint.config.js
import {
  combine,
  comments,
  ignores,
  imports,
  javascript,
  jsdoc,
  jsonc,
  markdown,
  node,
  sortPackageJson,
  sortTsconfig,
  stylistic,
  typescript,
  unicorn,
  vue,
  yaml
} from '@luxass/eslint-config'

export default combine(
  ignores(),
  javascript(/* Options */),
  comments(),
  node(),
  jsdoc(),
  imports(),
  unicorn(),
  typescript(/* Options */),
  stylistic(),
  vue(),
  jsonc(),
  yaml(),
  markdown(),
)

Check out the configs and factory for more details.

Thanks to sxzz/eslint-config and antfu/eslint-config for the inspiration and references.

Plugins Renaming

Since flat config requires us to explicitly provide the plugin names (instead of mandatory convention from NPM package name), we renamed some plugins to make overall scope more consistent and easier to write.

When you want to override rules, or disable them inline, you need to update to the new prefix:

-// eslint-disable-next-line @typescript-eslint/consistent-type-definitions
+// eslint-disable-next-line ts/consistent-type-definitions
type foo = { bar: 2 }

!NOTE About plugin renaming - it is actually rather a dangerous move that might lead to potential naming collisions, pointed out here and here. As this config also very personal and opinionated, I ambitiously position this config as the only "top-level" config per project, that might pivot the taste of how rules are named.

This config cares more about the user-facings DX, and try to ease out the implementation details. For example, users could keep using the semantic import/order without ever knowing the underlying plugin has migrated twice to eslint-plugin-i and then to eslint-plugin-import-x. User are also not forced to migrate to the implicit i/order halfway only because we swapped the implementation to a fork.

That said, it's probably still not a good idea. You might not want to do this if you are maintaining your own ESLint config.

Feel free to open issues if you want to combine this config with some other config presets but faced naming collisions. I am happy to figure out a way to make them work. But at this moment I have no plan to revert the renaming.

Since v4.3.0, this preset will automatically rename the plugins also for your custom configs. You can use the original prefix to override the rules directly.

Rules Overrides

Certain rules would only be enabled in specific files, for example, ts/* rules would only be enabled in .ts files and vue/* rules would only be enabled in .vue files. If you want to override the rules, you need to specify the file extension:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass(
  {
    vue: true,
    typescript: true
  },
  {
    // Remember to specify the file glob here, otherwise it might cause the vue plugin to handle non-vue files
    files: ['**/*.vue'],
    rules: {
      'vue/operator-linebreak': ['error', 'before'],
    },
  },
  {
    // Without `files`, they are general rules for all files
    rules: {
      'style/semi': ['error', 'never'],
    },
  }
)

We also provided a overrides options in each integration to make it easier:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  vue: {
    overrides: {
      'vue/operator-linebreak': ['error', 'before'],
    },
  },
  typescript: {
    overrides: {
      'ts/consistent-type-definitions': ['error', 'interface'],
    },
  },
  yaml: {
    overrides: {
      // ...
    },
  },
})

Config Composer

Since v4.3.0, the factory function luxass() returns a FlatConfigComposer object from eslint-flat-config-utils where you can chain the methods to compose the config even more flexibly.

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass()
  .prepend(
    // some configs before the main config
  )
  // overrides any named configs
  .override(
    'luxass/imports',
    {
      rules: {
        'import/order': ['error', { 'newlines-between': 'always' }],
      }
    }
  )
  // rename plugin prefixes
  .renamePlugins({
    'old-prefix': 'new-prefix',
    // ...
  })
// ...

Optional Configs

We provide some optional configs for specific use cases, that we don't include their dependencies by default.

Formatters

Use external formatters to format files that ESLint cannot handle yet (.css, .html, etc.). Powered by eslint-plugin-format.

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  formatters: {
    /**
     * Format CSS, LESS, SCSS files, also the `<style>` blocks in Vue
     * By default uses Prettier
     */
    css: true,
    /**
     * Format HTML files
     * By default uses Prettier
     */
    html: true,
    /**
     * Format Markdown files
     * Supports Prettier and dprint
     * By default uses Prettier
     */
    markdown: 'prettier'
  }
})

Running npx eslint should prompt you to install the required dependencies, otherwise, you can install them manually:

npm i -D eslint-plugin-format

React

To enable React support, you need to explicitly turn it on:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  react: true,
})

Running npx eslint should prompt you to install the required dependencies, otherwise, you can install them manually:

npm i -D @eslint-react/eslint-plugin eslint-plugin-react-hooks eslint-plugin-react-refresh

Next.JS

To enable Next.JS support, need to explicitly turn it on:

Next.JS also enables React support.

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  nextjs: true,
})

Running npx eslint should prompt you to install the required dependencies, otherwise, you can install them manually:

npm i -D eslint-plugin-react eslint-plugin-react-hooks @next/eslint-plugin-next

Astro

To enable Astro support, you need to explicitly turn it on:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  astro: true,
})

Running npx eslint should prompt you to install the required dependencies, otherwise, you can install them manually:

npm i -D eslint-plugin-astro

UnoCSS

To enable UnoCSS support, you need to explicitly turn it on:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  unocss: true,
})

Running npx eslint should prompt you to install the required dependencies, otherwise, you can install them manually:

npm i -D @unocss/eslint-plugin

TailwindCSS

To enable TailwindCSS support, need to explicitly turn it on:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  tailwindcss: true,
})

Running npx eslint should prompt you to install the required dependencies, otherwise, you can install them manually:

npm i -D eslint-plugin-tailwindcss

Optional Rules

This config also provides some optional plugins/rules for extended usages.

Type Aware Rules

You can optionally enable the type aware rules by passing the options object to the typescript config:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  typescript: {
    tsconfigPath: 'tsconfig.json',
  },
})

Editor Specific Disables

Some rules are disabled when inside ESLint IDE integrations, namely unused-imports/no-unused-imports test/no-focused-tests

This is to prevent unused imports from getting removed by the IDE during refactoring to get a better developer experience. Those rules will be applied when you run ESLint in the terminal or Lint Staged. If you don't want this behavior, you can disable them:

// eslint.config.js
import luxass from '@luxass/eslint-config'

export default luxass({
  editor: false
})

Lint Staged

If you want to apply lint and auto-fix before every commit, you can add the following to your package.json:

{
  "simple-git-hooks": {
    "pre-commit": "pnpm lint-staged"
  },
  "lint-staged": {
    "*": "eslint --fix"
  }
}

and then

npm i -D lint-staged simple-git-hooks

// to active the hooks
npx simple-git-hooks

View what rules are enabled

antfu built a visual tool to help you view what rules are enabled in your project and apply them to what files, @eslint/config-inspector

Go to your project root that contains eslint.config.js and run:

npx @eslint/config-inspector

Versioning Policy

This project follows Semantic Versioning for releases. However, since this is just a config and involves opinions and many moving parts, we don't treat rules changes as breaking changes.

Changes Considered as Breaking Changes

• Node.js version requirement changes
• Huge refactors that might break the config
• Plugins made major changes that might break the config
• Changes that might affect most of the codebases

Changes Considered as Non-breaking Changes

• Enable/disable rules and plugins (that might become stricter)
• Rules options changes
• Version bumps of dependencies

📄 License

Published under MIT License.