Introducing Stylelint

Stylelint is a linter for CSS files and can be extended to also understand CSS dialects such as SCSS, Sass, Less, or SugarCSS. It has over 170 built-in rules but, much like ESLint, provides support for custom rules.

To install Stylelint, we can follow the same steps as with ESLint:

1. Here, it usually makes sense to rely on the standard configuration provided by Stylelint. Unlike ESLint, the standard configuration is released in a separate package and, therefore, needs to be installed as well. The command to install both packages as development dependencies looks like this:

   $ npm install stylelint stylelint-config-standard

     --save-dev

2. In any case, we still require a configuration file. For the moment, it is sufficient to just let stylelint know that we want to use the configuration from the stylelint-config-standard package. Here, we can write another configuration file next to the project’s package.json:

.stylelintrc...