Adding ESLint with gulp.js
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!
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
.eslintignoreto specify directories and files to avoid for linting, fornode_modulesfor example.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
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.