Adding ESLint with gulp.js

By  on  

I've noticed that I am a loose coder on my personal projects but want some level of decorum on Mozilla and other open source projects.  The more developers you have contributing to a project, the tighter the ship you must keep.  The easiest way to do that is requiring contributions to meet a certain code convention criteria via a tool like ESLint.  Since I like to use gulp.js for my build process, I thought I'd share a very basic use of ESLint for your project.

You start by adding ESLint to your package.json file or installing via NPM manually:

npm install gulp-eslint

With ESLint available somewhere within the node path, you can set up a lint task within your gulpfile.js:

gulp.task('lint', function() {
  return gulp.src('lib/**').pipe(eslint({
    'rules':{
        'quotes': [1, 'single'],
        'semi': [1, 'always']
    }
  }))
  .pipe(eslint.format())
  // Brick on failure to be super strict
  .pipe(eslint.failOnError());
});

You can get a full list of rules and possible values here.  How strict you want to be depends on your general philosophy within JavaScript.  Many people make lint a part of their test task as well so that travis-ci can reject code that isn't up to snuff.

Now that I've written this post, I'll probably take the time to add ESLint to my personal projects so that I can get in the habit of always coding to a certain standard.  Practice makes perfect!

Recent Features

  • By
    CSS @supports

    Feature detection via JavaScript is a client side best practice and for all the right reasons, but unfortunately that same functionality hasn't been available within CSS.  What we end up doing is repeating the same properties multiple times with each browser prefix.  Yuck.  Another thing we...

  • By
    5 More HTML5 APIs You Didn’t Know Existed

    The HTML5 revolution has provided us some awesome JavaScript and HTML APIs.  Some are APIs we knew we've needed for years, others are cutting edge mobile and desktop helpers.  Regardless of API strength or purpose, anything to help us better do our job is a...

Incredible Demos

  • By
    MooTools Equal Heights Plugin:  Equalizer

    Keeping equal heights between elements within the same container can be hugely important for the sake of a pretty page. Unfortunately sometimes keeping columns the same height can't be done with CSS -- you need a little help from your JavaScript friends. Well...now you're...

  • By
    Jack Rugile’s Favorite CodePen Demos

    CodePen is an amazing source of inspiration for code and design. I am blown away every day by the demos users create. As you'll see below, I have an affinity toward things that move. It was difficult to narrow down my favorites, but here they are!

Discussion

  1. Bradley

    One thing you’d likely want to handle differently is putting your linting rules in the root directory of your project in a file named .eslintrc. Then it’s won’t bloat up your gulpfile if you have lots of rules, stays in your git repos, etc.

    There’s also a .eslintignore to specify directories and files to avoid for linting, for node_modules for example.

  2. I can recommend using lints as Editor/Ide plugins.
    It may be annoying (errors and warning pop up while you write) but on the other hand it helps to learn the style.

    Atom has quite collection of various lints: https://atom.io/users/AtomLinter

  3. nathan

    gulp-eslint has not been updated for a while and still uses ESLint 6 instead of ESLint 8, missing a lot of new features. I would recommend using an alternative that is actively maintained like gulp-eslint-new, or simply running ESLint as an npm task.

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!