JavaScript Semi-Standard Style

One Semicolon for the Dark Lord on his dark throne

All the goodness of feross/standard with semicolons sprinkled on top.

One Style to Rule Them All

No decisions to make. No .eslintrc, .jshintrc, or .jscsrc files to manage. It just works.

This module saves you (and others!) time in two ways:

• No configuration. The easiest way to enforce consistent style in your project. Just drop it in.
• Catch style errors before they're submitted in PRs. Saves precious code review time by eliminating back-and-forth between maintainer and contributor.

Install

npm install GerHobbelt/semistandard

Rules

Importantly:

• semicolons

• Check feross/standard for the rest of the rules:

  • 2 spaces – for indentation
  • Single quotes for strings – except to avoid escaping
  • No unused variables – this one catches tons of bugs!
  • No semicolons – It's fine. Really!
  • Never start a line with ( or [
    • This is the only gotcha with omitting semicolons – automatically checked for you!
    • More details
  • Space after keywords if (condition) { ... }
  • Space after function name function name (arg) { ... }
  • Always use === instead of == – but obj == null is allowed to check null || undefined.
  • Always handle the node.js err function parameter
  • Always prefix browser globals with window – except document and navigator are okay
    • Prevents accidental use of poorly-named browser globals like open, length, event, and name.
  • And more goodness – give standard a try today!

To get a better idea, take a look at a sample file written in JavaScript Standard Style, or check out some of the repositories that use standard.

Badge

Use this in one of your projects? Include one of these badges in your readme to let people know that your code is using the standard style.

[![js-semistandard-style](https://cdn.rawgit.com/flet/semistandard/master/badge.svg)](https://github.com/Flet/semistandard)

[![js-semistandard-style](https://img.shields.io/badge/code%20style-semistandard-brightgreen.svg?style=flat-square)](https://github.com/Flet/semistandard)

Usage

The easiest way to use JavaScript Semi-Standard Style to check your code is to install it globally as a Node command line program. To do so, simply run the following command in your terminal (flag -g installs semistandard globally on your system, omit it if you want to install in the current working directory):

npm install semistandard -g

After you've done that you should be able to use the semistandard program. The simplest use case would be checking the style of all JavaScript files in the current working directory:

$ semistandard
Error: Use JavaScript Semi-Standard Style
  lib/torrent.js:950:11: Expected '===' and instead saw '=='.

You can optionally pass in a directory (or directories) using the glob pattern. Be sure to quote paths containing glob patterns so that they are expanded by semistandard instead of your shell:

$ semistandard "src/util/**/*.js" "test/**/*.js"

Note: by default semistandard will look for all files matching the patterns: **/*.js, **/*.jsx.

Text editor plugins

First, install semistandard. Then, install the appropriate plugin for your editor:

• Sublime users: Try SublimeLinter-contrib-semistandard for linting in your editor!
• Atom users - Install linter-js-standard

Formatting code to Semistandard

• CLI - semistandard-format
• Atom plugin - standard-formatter
• Sublime Text plugin - StandardFormat
• VS Code plugin - JavaScript Semi-Standard Format

Despite their names, all the above plugins support both standard and semistandard.

What you might do if you're clever

1. Add it to package.json

{
  "name": "my-cool-package",
  "devDependencies": {
    "semistandard": "*"
  },
  "scripts": {
    "test": "semistandard && node my-normal-tests-littered-with-semicolons.js"
  }
}

2. Check style automatically when you run npm test

$ npm test
Error: Code style check failed:
  lib/torrent.js:950:11: Expected '===' and instead saw '=='.

3. Never give style feedback on a pull request again! (unless it's about semicolons)

Custom Parser

To use a custom parser, install it from npm (example: npm install babel-eslint) and add this to your package.json:

{
  "semistandard": {
    "parser": "babel-eslint"
  }
}

Vim

Install Syntastic and add these lines to .vimrc:

let g:syntastic_javascript_checkers=['standard']
let g:syntastic_javascript_standard_exec = 'semistandard'

For automatic formatting on save, add these two lines to .vimrc:

autocmd bufwritepost *.js silent !semistandard % --format
set autoread

Ignoring files

Just like in standard, The paths node_modules/**, *.min.js, bundle.js, coverage/**, hidden files/folders (beginning with .), and all patterns in a project's root .gitignore file are automatically excluded when looking for .js files to check.

Sometimes you need to ignore additional folders or specific minfied files. To do that, add a semistandard.ignore property to package.json:

"semistandard": {
  "ignore": [
    "**/out/",
    "/lib/select2/",
    "/lib/ckeditor/",
    "tmp.js"
  ]
}

Make it look snazzy

If you want prettier output, just install the snazzy package and pipe semistandard to it:

$ semistandard --verbose | snazzy

See feross/standard for more information.