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 with:

npm install nodeos-standard

The rules

For a quick list of the rules, please refer to ESLint's recommended rules here.

The specific additions to these rules are as followed:

• semicolons are optional
• Unix style line breaks

Table of Contents

• Install
• Usage
  • What you might do if you're clever
• FAQ
  • How do I ignore files?
  • How do I hide a certain warning?
  • I use a library that pollutes the global namespace. How do I prevent "variable is not defined" errors?
  • Can I use a custom JS parser for bleeding-edge ES6 or ES7 support?
  • What about Web Workers?
  • What about Mocha, Jasmine, QUnit, etc?
  • Is there a Git pre-commit hook?
  • How do I make the output all colorful and pretty?
• Node.js API
  • standard.lintText(text, [opts], callback)
  • standard.lintFiles(files, [opts], callback)
• License

Install

The easiest way to use NodeOS 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 standard globally on your system, omit it if you want to install in the current working directory):

npm install nodeos-standard --global

Or, you can run this command to install nodeos-standard locally, for use in your module:

npm install nodeos-standard --save-dev

Node.js and npm are required to run the preceding commands.

Usage

After you've installed nodeos-standard, you should be able to use the nodeos-standard program. The simplest use case would be checking the style of all JavaScript files in the current working directory:

$ nodeos-standard
Error: Use NodeOS 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 nodeos-standard instead of your shell:

$ nodeos-standard "src/util/**/*.js" "test/**/*.js"

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

What you might do if you're clever

1. Add it to package.json

{
  "name": "my-cool-package",
  "devDependencies": {
    "nodeos-standard": "*"
  },
  "scripts": {
    "test": "nodeos-standard && node my-tests.js"
  }
}

2. Check style automatically when you run npm test

$ npm test
Error: Use NodeOS Standard Style
  lib/torrent.js:950:11: Expected '===' and instead saw '=='.

3. Never give style feedback on a pull request again!

How do I ignore files?

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 ignored.

Sometimes you need to ignore additional folders or specific minified files. To do that, add a nodeos-standard.ignore property to package.json:

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

FAQ

How do I hide a certain warning?

In rare cases, you'll need to break a rule and hide the warning generated by nodeos-standard.

NodeOS Standard Style uses eslint under-the-hood and you can hide warnings as you normally would if you used eslint directly.

To get verbose output (so you can find the particular rule name to ignore), run:

$ nodeos-standard --verbose
Error: Use NodeOS Standard Style
  routes/error.js:20:36: 'file' was used before it was defined. (no-use-before-define)

Disable all rules on a specific line:

file = 'I know what I am doing' // eslint-disable-line

Or, disable only the "no-use-before-define" rule:

file = 'I know what I am doing' // eslint-disable-line no-use-before-define

Or, disable the "no-use-before-define" rule for multiple lines:

/* eslint-disable no-use-before-define */
console.log('offending code goes here...')
console.log('offending code goes here...')
console.log('offending code goes here...')
/* eslint-enable no-use-before-define */

I use a library that pollutes the global namespace. How do I prevent "variable is not defined" errors?

Some packages (e.g. mocha) put their functions (e.g. describe, it) on the global object (poor form!). Since these functions are not defined or required anywhere in your code, nodeos-standard will warn that you're using a variable that is not defined (usually, this rule is really useful for catching typos!). But we want to disable it for these global variables.

To let nodeos-standard (as well as humans reading your code) know that certain variables are global in your code, add this to the top of your file:

/* global myVar1, myVar2 */

If you have hundreds of files, adding comments to every file can be tedious. In these cases, you can add this to package.json:

{
  "nodeos-standard": {
    "globals": [ "myVar1", "myVar2" ]
  }
}

Can I use a custom JS parser for bleeding-edge ES6 or ES7 support?

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

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

If you're using nodeos-standard globally (you installed it with -g), then you also need to install babel-eslint globally with npm install babel-eslint -g.

What about Web Workers?

Add this to the top of your files:

/* eslint-env serviceworker */

This lets nodeos-standard (as well as humans reading your code) know that self is a global in web worker code.

What about Mocha, Jasmine, QUnit, etc?

To support mocha in your test files, add this to the beginning of your test files:

/* eslint-env mocha */

Where mocha can be one of jasmine, qunit, phantomjs, and so on. To see a full list, check ESLint's specifying environments documentation. For a list of what globals are available for these environments, check the globals npm module.

Is there a Git pre-commit hook?

Funny you should ask!

#!/bin/sh
# Ensure all javascript files staged for commit pass standard code style
git diff --name-only --cached --relative | grep '\.jsx\?$' | xargs nodeos-standard
if [ $? -ne 0 ]; then exit 1; fi

How do I make the output all colorful and pretty?

The built-in output is simple and straightforward, but if you like shiny things, install snazzy:

npm install snazzy

And run:

$ nodeos-standard --verbose | snazzy

There's also standard-tap, standard-json, standard-reporter, and standard-summary.

Node.js API

nodeos-standard.lintText(text, [opts], callback)

Lint the provided source text to enforce JavaScript Standard Style. An opts object may be provided:

var opts = {
  globals: [],  // global variables to declare
  parser: ''    // custom js parser (e.g. babel-eslint)
}

The callback will be called with an Error and results object:

var results = {
  results: [
    {
      filePath: '',
      messages: [
        { ruleId: '', message: '', line: 0, column: 0 }
      ],
      errorCount: 0,
      warningCount: 0
    }
  ],
  errorCount: 0,
  warningCount: 0
}

nodeos-standard.lintFiles(files, [opts], callback)

Lint the provided files globs. An opts object may be provided:

var opts = {
  globals: [],  // global variables to declare
  parser: '',   // custom js parser (e.g. babel-eslint)
  ignore: [],   // file globs to ignore (has sane defaults)
  cwd: ''       // current working directory (default: process.cwd())
}

The callback will be called with an Error and results object (same as above).

License

MIT. Copyright (c) Feross Aboukhadijeh.