Opinionated Eslint Setup

Eslint modularized config based on Andres Troinano rules.

Support for React, Typescript and Node projects with or without Prettier.

What it does

• Lints JavaScript and Typescript based with our opinionated rules
• Fixes issues and formatting errors with Prettier

Installing

1. If you don't already have a package.json file, create one with npm init.

2. Then we need to install everything needed by the config:

npx install-peerdeps --dev eslint-config-restrictor

3. You can see in your package.json there are now a few list of devDependencies.

4. Create a .eslintrc file in the root of your project's directory (it should live where package.json does). Your .eslintrc file should look like this:

{
  "extends": ["restrictor"]
}

Tip: You can alternatively put this object in your package.json under the property "eslintConfig":. This makes one less file in your project.

5. You can add two scripts to your package.json to lint and/or fix:

"scripts": {
  "lint": "eslint './**/*.{js,jsx,ts,tsx}'",
  "lint:fix": "eslint './**/*.{js,jsx,ts,tsx}' --fix"
},

6. Now you can manually lint your code by running npm run lint and fix all fixable issues with npm run lint:fix. You probably want your editor to do this though.

Add additional configuration

A few extra configuration files are available but they require additionals dependencies. You can combine them.

React

For react projects you should also extend this configuration.

npm install -D eslint-config-react-app eslint-plugin-react eslint-plugin-flowtype eslint-plugin-import eslint-plugin-react-hooks eslint-plugin-jsx-a11y

And extend your .eslintrc file.

{
  "extends": ["restrictor", "restrictor/react"]
}

Typescript

For Typescript project you should also extend this configuration.

npm install -D @typescript-eslint/eslint-plugin @typescript-eslint/parser eslint-import-resolver-typescript

And extend your .eslintrc file

{
  "extends": ["restrictor", "restrictor/typescript"]
}

Node.js

For use in a node.js project you should also extend this configuration.

npm install -D eslint-plugin-import eslint-plugin-node eslint-plugin-promise

And extend your .eslintrc file.

{
  "extends": ["restrictor", "restrictor/node"]
}

Prettier

For use prettier in your project you should also extend this configuration.

npm install -D prettier eslint-plugin-prettier eslint-config-prettier

And extend your .eslintrc file.

{
  "extends": ["restrictor", "restrictor/prettier"]
}

Important note: restrictor/prettier should be placed last because overrides some rules from the other config files.

All of them!

You can use them all together if the project requires.

Install all devDependencies together.

npm install -D eslint-config-react-app eslint-plugin-react eslint-plugin-flowtype eslint-plugin-import eslint-plugin-react-hooks eslint-plugin-jsx-a11y @typescript-eslint/eslint-plugin @typescript-eslint/parser prettier eslint-plugin-prettier eslint-config-prettier

And add all the config files to .eslintrc.

{
  "extends": [
    "restrictor",
    "restrictor/react",
    "restrictor/typescript",
    "restrictor/prettier"
  ]
}

Settings

If you'd like to overwrite eslint or prettier settings, you can add the rules in your .eslintrc file. The ESLint rules go directly under "rules" while prettier options can be defined in a .prettierrc file or go under "prettier/prettier". Note that prettier rules overwrite anything in my config (trailing comma, and single quote), so you'll need to include those as well.

{
  "extends": [
    "restrictor"
  ],
  "rules": {
    "no-console": 2,
    "prettier/prettier": [
      "error",
      {
        "semi": false,
        "singleQuote": true
      }
    ]
  }
}

OR in a .prettierrc.

{
  "semi": false,
  "singleQuote": true
}

With VS Code

Once you have done the above installs. You probably want your editor to lint and fix for you. Here are the instructions for VS Code:

1. Install the ESLint package
2. Now we need to setup some VS Code settings via Code/File → Preferences → Settings. It's easier to enter these settings while editing the settings.json file, so click the {} icon in the top right corner:

// These are all my auto-save configs
"editor.formatOnSave": true,
// turn it off for JS and JSX, we will do this via eslint
"[javascript]": {
  "editor.formatOnSave": false
},
"[javascriptreact]": {
  "editor.formatOnSave": false
},
// tell the ESLint plugin to run on save
"eslint.autoFixOnSave": true,
// turn on eslint on .js,.jsx,.ts and .tsx files
"eslint.validate": [
  "javascript",
  "javascriptreact",
  "typescript",
  "typescriptreact"
],