Value No Unknown Custom Properties is a stylelint rule to disallow usage of unknown custom properties.
Add stylelint and Value No Unknown Custom Properties to your project.
npm install stylelint stylelint-value-no-unknown-custom-properties --save-dev
Add Value No Unknown Custom Properties to your stylelint configuration.
{
"plugins": [
"stylelint-value-no-unknown-custom-properties"
],
"rules": {
"csstools/value-no-unknown-custom-properties": true || false || null
}
}
If the first option is true
, then Value No Unknown Custom Properties
requires all custom properties to be known, and the following patterns are
not considered violations:
:root {
--brand-blue: #33f;
}
.example {
color: var(--brand-blue);
}
.example {
color: var(--brand-blue);
}
.some-other-class {
--brand-blue: #33f;
}
:root {
--brand-blue: #33f;
--brand-color: var(--brand-blue);
}
While the following patterns are considered violations:
.example {
color: var(--brand-blue);
}
:root {
--brand-color: var(--brand-blue);
}
Custom Properties can be imported using the second option.
If the first option is false
or null
, then
Value No Unknown Custom Properties does nothing.
When the first option is true
, then the second option can specify sources
where Custom Properties should be imported from by using an importFrom
key.
These imports might be CSS, JS, and JSON files, functions, and directly passed
objects.
// .stylelintrc
{
"plugins": [
"stylelint-value-no-unknown-custom-properties"
],
"rules": {
"csstools/value-no-unknown-custom-properties": [true, {
"importFrom": [
"path/to/file.css", // => :root { --brand-blue: #33f; }
"path/to/file.json" // => { "custom-properties": { "--brand-blue": "#33f" } }
]
}
}
}