stylelint-no-unused-custom-properties

Remove or report on unused variable definitions

Installation

yarn add -D @spectrum-tools/stylelint-no-unused-custom-properties

Usage

Assuming you have some variables defined and rule(s) that use them:

:root {
  --prefix-component-background-color: blue;
  --prefix-component-width: 10px;
  --prefix-component-height: 10px;
  --prefix-component-size: 10px;
}

.component {
  background-color: var(--prefix-component-background-color);

  width: var(--prefix-component-width);
  height: var(--prefix-component-height);
}

The variables that are not used in any rule will be removed from the output or reported to the console:

:root {
  --prefix-component-background-color: blue;
  --prefix-component-width: 10px;
  --prefix-component-height: 10px;
}

.component {
  background-color: var(--prefix-component-background-color);

  width: var(--prefix-component-width);
  height: var(--prefix-component-height);
}

To allow variables to be defined without being used, such as when you want to pass custom properties down to a child component, you can add a /* @passthrough */ comment to the variable definition:

:root {
  /* @passthrough */
  --nested-component-background-color: blue;
  --prefix-component-width: 10px;
  --prefix-component-height: 10px;
  --prefix-component-size: 10px;
}

To allow a group of properties to be passed down, you can prefix the set with /* @passthrough start */ and suffix it with /* @passthrough end */:

:root {
  /* @passthrough start */
  --nested-component-background-color: blue;
  --nested-component-width: 10px;
  /* @passthrough end */

  --prefix-component-height: 10px;
  --prefix-component-size: 10px;
}

Options

ignoreList (default: [])

An array of strings or regular expressions that will be matched against the variable name. If a match is found, the variable will be ignored.