stylelint-css-modules-no-global-scoped-selector

Stylelint rule for CSS modules to prevent usage of global-scoped selectors.

To be scoped locally a selector must contain at least one local class or id, otherwise the selector can have unwanted effects on other elements. More information is available on the CSS Modules documentation.

Internally this rule uses the same logic as css-loader to check if a selector is pure i.e. scoped locally. The concept of pure selector is explained in the readme of css-loader.

✅ Example of local-scoped selectors:

// SCSS

.container {
  // ...
}

.container {
  :global .external-class {
    // ...
  }
}

❌ Example of global-scoped selectors:

// SCSS

h1 {
  // ...
}

:global .external-class {
  // ...
}

h1 {
  :global .external-class {
    // ...
  }
}

Installation

Install the plugin:

# npm
npm i stylelint-css-modules-no-global-scoped-selector --save-dev

# yarn
yarn add stylelint-css-modules-no-global-scoped-selector --dev

Update your stylelint.config.js:

module.exports = {
  plugins: [
    ...,
+   "stylelint-css-modules-no-global-scoped-selector",
  ],
  rules: {
    ...,
+   "css-modules/no-global-scoped-selector": true,
  },
}

Configuration

If you don't want to check all your CSS files, you can use the fileExtensions option to specify which file extensions you want to check. For example, if your project contains CSS and SCSS modules all ending with .module.css or .module.scss you can update your stylelint.config.js like this:

module.exports = {
  plugins: [
    ...,
+   "stylelint-css-modules-no-global-scoped-selector",
  ],
  rules: {
    ...,
+   "css-modules/no-global-scoped-selector": [
+     true,
+     { fileExtensions: [".module.css", ".module.scss"] },
+   ],
  },
}