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

A collection of stylistic/formatting Stylelint rules

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

/**
 * Checks whether a value is standard (i.e. not a preprocessor construct).
 * @param {string} value - The value to check.
 * @returns {boolean} True if the value is standard syntax, false otherwise.
 */
export function isStandardSyntaxValue (value) {
	let normalizedValue = value

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

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

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

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

	return true
}