What is the problem you're trying to solve?

Thanks to the CSS Houdini API, the property name of a custom property could appear in the value of some declarations, such as transition (or more precisely, transition-property). However, the current custom-property-no-missing-var-function rule will report errors for these custom property names that are not wrapped in var().

Online demo

What solution would you like to see?

One possibility is to not report transition, etc. by default, but this could also produce breaking changes.

It is also possible to add options to the rule to ignore certain property names, as we did in property-no-vendor-prefix.

module.exports = {
  rules: {
    'custom-property-no-missing-var-function': [true, { ignoreProperties: ['transition', 'transition-property'] }],
  }
}