Mark Hkr Eslint and Prettier Setup

My settings for ESLint and Prettier

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.

Local / Per Project Install

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

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

npx install-peerdeps --dev eslint-config-markhkr

3. 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": [
    "markhkr"
  ]
}

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

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

5. Now you can manually lint your code by running npm run lint and fix all fixable issues with npm run lint:fix.

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 this config (trailing comma, and single quote), so you'll need to include those as well.

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

With VS Code

Once you have done the install. 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 Open (Open Settings) 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
},
// show eslint icon at bottom toolbar
"eslint.alwaysShowStatus": true,
// tell the ESLint plugin to run on save
"editor.codeActionsOnSave": {
  "source.fixAll": 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"],

After attempting to lint your file for the first time, you may need to click on 'ESLint' in the bottom right and select 'Allow Everywhere' in the alert window.

Finally you'll usually need to restart VS code. They say you don't need to, but it's never worked for me until I restart.

With Create React App

1. Run npx install-peerdeps --dev eslint-config-markhkr
2. Crack open your package.json and replace "extends": "react-app" with "extends": "markhkr"

With Yarn

It should just work, but if they aren't showing up in your package.json, try npx install-peerdeps --dev eslint-config-markhkr -Y