@stylistic/stylelint-plugin/lib/utils/atRuleParamIndex/index.js

A collection of stylistic/formatting Stylelint rules

/**
 * @param {import('postcss').AtRule} atRule
 * @returns {number}
 */
export function atRuleParamIndex (atRule) {
	// Initial 1 is for the `@`
	let index = 1 + atRule.name.length

	if (atRule.raws.afterName) {
		index += atRule.raws.afterName.length
	}

	return index
}