@sncat/eslint-config v1.0.0-alpha.3

@sncat/eslint-config

• Single quotes, no semi
• Auto fix for formatting (aimed to be used standalone without Prettier)
• Designed to work with TypeScript, Vue out-of-box
• Lints also for json, yaml, markdown
• Sorted imports, dangling commas
• Reasonable defaults, best practices, only one-line of config
• Respects .gitignore by default
• ESLint Flat config, compose easily!
• Using ESLint Stylistic
• Style principle: Minimal for reading, stable for diff, consistent

!IMPORTANT The main branch is for v1.0-beta, which rewrites to ESLint Flat config, check #250 for more details.

Usage

Install

pnpm add -D eslint @sncat/eslint-config

Create config file

With "type": "module" in package.json (recommended):

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

export default sncat()

With CJS:

// eslint.config.js
const sncat = require('@sncat/eslint-config').default

module.exports = sncat()

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"
  }
}

VS Code support (auto fix)

Install VS Code ESLint extension

Add the following settings to your .vscode/settings.json:

{
  // Enable the ESlint flat config support
  "eslint.experimental.useFlatConfig": true,

  // Disable the default formatter, use eslint instead
  "prettier.enable": false,
  "editor.formatOnSave": false,

  // Auto fix
  "editor.codeActionsOnSave": {
    "source.fixAll.eslint": true,
    "source.organizeImports": false
  },

  // 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" }
  ],

  // Enable eslint for all supported languages
  "eslint.validate": [
    "javascript",
    "javascriptreact",
    "typescript",
    "typescriptreact",
    "vue",
    "html",
    "markdown",
    "json",
    "jsonc",
    "yaml"
  ]
}

Customization

Since v1.0, we migrated to ESLint Flat config. It provides much better organization and composition.

Normally you only need to import the antfu preset:

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

export default sncat()

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

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

export default sncat({
  stylistic: true, // enable stylistic formatting rules
  typescript: true,
  vue: true,
  jsonc: false, // disable jsonc support
  yaml: false,

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

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

// eslint.config.js
import sncat from '@antfu/eslint-config'

export default sncat(
  {
    // Configures for sncat'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:

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

export default [
  ...ignores(),
  ...javascript(),
  ...comments(),
  ...node(),
  ...jsdoc(),
  ...imports(),
  ...unicorn(),
  ...typescript(),
  ...stylistic(),
  ...vue(),
  ...jsonc(),
  ...yml(),
  ...markdown(),
]

Check out the configs and factory for more details.

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 }

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 sncat from '@sncat/eslint-config'

export default sncat(
  { 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 an overrides options to make it easier:

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

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

Type Aware Rules

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

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

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

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

Badge

If you enjoy this code style, and would like to mention it in your project, here is the badge you can use:

[![code style](https://antfu.me/badge-code-style.svg)](https://github.com/antfu/eslint-config)

FAQ

Prettier?

Why I don't use Prettier

How to lint CSS?

This config does NOT lint CSS. I personally use UnoCSS so I don't write CSS. If you still prefer CSS, you can use stylelint for CSS linting.

I prefer XXX...

Sure, you can config and override rules locally in your project to fit your needs. If that still does not work for you, you can always fork this repo and maintain your own.

Check Also

• antfu/dotfiles - My dotfiles
• antfu/vscode-settings - My VS Code settings
• antfu/ts-starter - My starter template for TypeScript library
• antfu/vitesse - My starter template for Vue & Vite app

License

MIT License © 2019-PRESENT Anthony Fu