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

A collection of stylistic/formatting Stylelint rules

import { hasInterpolation } from "../hasInterpolation/index.js"

/**
 * Check whether a value is standard
 *
 * @param {string} value
 * @returns {boolean}
 */
export function isStandardSyntaxValue (value) {
	let normalizedValue = value

	// Ignore operators before variables (example -$variable)
	if ((/^[-+*/]/).test(value.charAt(0))) {
		normalizedValue = normalizedValue.slice(1)
	}

	// SCSS variable (example $variable)
	if (normalizedValue.startsWith(`$`)) {
		return false
	}

	// SCSS namespace (example namespace.$variable)
	if ((/^.+\.\$/).test(value)) {
		return false
	}

	// SCSS namespace (example namespace.function-name())
	if ((/^.+\.[-\w]+\(/).test(value)) {
		return false
	}

	// Less variable
	if (normalizedValue.startsWith(`@`)) {
		return false
	}

	// SCSS or Less interpolation
	if (hasInterpolation(normalizedValue)) {
		return false
	}

	// WebExtension replacement keyword used by Chrome/Firefox
	// more information: https://developer.chrome.com/extensions/i18n
	// and https://github.com/stylelint/stylelint/issues/4707
	if ((/__MSG_\S+__/).test(value)) {
		return false
	}

	return true
}