Eslint and Prettier Setup

Custom settings for ESLint and Prettier, forked from Wes Bos's original setup, for my personal use. This version is actively updated to be compatible with the latest Create-React-App.

• What it does
• Installing
• Local Project Install
• Settings
• With VS Code
• With Create React App
• IT'S NOT WORKING

What it does

• Lints JavaScript based on the latest standards
• Fixes issues and formatting errors with Prettier
• Lints + Fixes inside of html script tags
• Lints + Fixes React via eslint-config-airbnb
• You can see all the rules here

Installing

You can use eslint globally and/or locally per project.

It's usually best to install this locally once per project, that way you can have project specific settings as well as sync those settings with others working on your project via git.

I also install globally so that any project or rogue JS file I write will have linting and formatting applied without having to go through the setup.

Local Project Install

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-eyy

1. You can see in your package.json there are now a big list of devDependencies.

2. 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": ["eyy"]
}

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

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

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

1. 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.

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 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": [
    "eyy"
  ],
  "rules": {
    "no-console": 2,
    "prettier/prettier": [
      "error",
      {
        "trailingComma": "es5",
        "singleQuote": true,
        "printWidth": 120,
        "tabWidth": 8,
      }
    ]
  }
}

With VS Code

You should read this entire thing. Serious!

⚠️ Eslint v6 with VScode only works with one project opened in VS code window, multiple projects in the same VS code window will not work because Eslint in VScode will look for modules in the current window's work directory.

Once you have done one, or both, of 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,
// Optional BUT IMPORTANT: If you have the prettier extension enabled for other languages like CSS and HTML, turn it off for JS since we are doing it through Eslint already
"prettier.disableLanguages": ["javascript", "javascriptreact"],

With Create React App

1. Run npx install-peerdeps --dev eslint-config-eyy
2. Crack open CRA's package.json:

replace:

  "eslintConfig": {
    "extends": "react-app"
  },

to:

  "eslintConfig": {
    "extends": ["react-app", "eyy"]
  },

IT'S NOT WORKING

Start fresh. Sometimes global modules can goof you up. This will remove them all.

npm remove --global eslint-config-eyy babel-eslint eslint eslint-config-prettier eslint-config-airbnb eslint-plugin-html eslint-plugin-prettier eslint-plugin-import eslint-plugin-jsx-a11y eslint-plugin-react prettier eslint-plugin-react-hooks

To do the above for local, omit the --global flag.

Then if you are using a local install, remove your package-lock.json file and delete the node_modules/ directory.

Then follow the above instructions again.