Linting and Formatting configuration with ESlint and Prettier

These are my settings for ESLint and Prettier

You might like them - or you might not. Don't worry you can always change them.

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. You might disagree and that is okay, just don't do it then 😃.

Local / Per 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-blaze

3. You can see in your package.json there are now a big 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": [ "blaze" ]
}

For TypeScript projects, use blaze/typescript.

{
  "extends": [ "blaze/typescript" ]
}

TypeScript users will also need a tsconfig.json file in their project. An empty object ({}) will do if this is a new project.

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 .",
  "lint:fix": "eslint . --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.

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": [
    "blaze"
  ],
  "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!

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 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
}

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-blaze
2. Crack open your package.json and replace "extends": "react-app" with "extends": "blaze"

With Gatsby

1. Run npx install-peerdeps --dev eslint-config-blaze
2. If you have an existing .prettierrc file, delete it.
3. follow the Local / Per Project Install steps above

With WSL

Can someone add this?

With JetBrains Products (IntelliJ IDEA, WebStorm, RubyMine, PyCharm, PhpStorm, etc)

If you have previously configured ESLint to run via a File Watcher, turn that off.

If you choose Local / Per Project Install Above

1. Open ESLint configuration by going to File > Settings (Edit > Preferences on Mac) > Languages & Frameworks > Code Quality Tools > ESLint (optionally just search settings for "eslint")
2. Select Automatic ESLint Configuration
3. Check Run eslint --fix on save

If you choose Global Install

The following steps are for a typical Node / ESLint global installtion. If you have a customized setup, refer to JetBrains docs for more ESLint Configuration Options.

1. Open ESLint configuration by going to File > Settings (Edit > Preferences on Mac) > Languages & Frameworks > Code Quality Tools > ESLint (optionally just search settings for "eslint")
2. Select Manual ESLint configuration
3. Choose your Node interpreter from the detected installations
4. Select the global ESLint package from the dropdown
5. Leave Configuration File as Automatic Search
6. Check Run eslint --fix on save

Ensure the Prettier plugin is disabled if installed.

1. Open Prettier configuration by going to File > Settings (Edit > Preferences on Mac) > Languages & Frameworks > Code Quality Tools > Prettier (optionally just search settings for "prettier")
2. Uncheck both On code reformat and On save
3. 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.
   1. Make sure the Run for files glob does not include js,ts,jsx,tsx.
   2. An example glob for styles, config, and markdown. {**/*,*}.{yml,css,sass,md}

With Typescript

Same instructions as above, just make sure you extend blaze/typescript instead of just blaze.

With Yarn

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