Matt Dell mattdell

Project-specific lint rules with ESLint

A quick introduction

First there was JSLint, and there was much rejoicing. The odd little language called JavaScript finally had some static code analysis tooling to go with its many quirks and surprising edge cases. But people gradually became annoyed with having to lint their code according to the rules dictated by Douglas Crockford, instead of their own.

So JSLint got forked into JSHint, and there was much rejoicing. You could set it up to only complain about the things you didn't want to allow in your project, and shut up about the rest. JSHint has been the de-facto standard JavaScript linter for a long while, and continues to do so. Yet there will always be things your linter could check for you, but doesn't: your team has agreed on some convention that makes sense for them, but JSHint doesn't have an option

	#!/bin/bash
	#
	# This program is free software. It comes without any warranty, to
	# the extent permitted by applicable law. You can redistribute it
	# and/or modify it under the terms of the Do What The Fuck You Want
	# To Public License, Version 2, as published by Sam Hocevar. See
	# http://sam.zoy.org/wtfpl/COPYING for more details.
	#

	# Version 3, enhanced for Ubuntu 13.X+, Fedora 19+, and similar distros.

	// @license http://opensource.org/licenses/MIT
	// copyright Paul Irish 2015


	// Date.now() is supported everywhere except IE8. For IE8 we use the Date.now polyfill
	// github.com/Financial-Times/polyfill-service/blob/master/polyfills/Date.now/polyfill.js
	// as Safari 6 doesn't have support for NavigationTiming, we use a Date.now() timestamp for relative values

	// if you want values similar to what you'd get with real perf.now, place this towards the head of the page
	// but in reality, you're just getting the delta between now() calls, so it's not terribly important where it's placed