@formatjs/ecma402-abstract/IsWellFormedUnitIdentifier.js

A collection of implementation for ECMAScript abstract operations

import { IsSanctionedSimpleUnitIdentifier } from "./IsSanctionedSimpleUnitIdentifier.js";
/**
* This follows https://tc39.es/ecma402/#sec-case-sensitivity-and-case-mapping
* @param str string to convert
*/
function toLowerCase(str) {
	return str.replace(/([A-Z])/g, (_, c) => c.toLowerCase());
}
/**
* https://tc39.es/ecma402/#sec-iswellformedunitidentifier
* @param unit
*/
export function IsWellFormedUnitIdentifier(unit) {
	unit = toLowerCase(unit);
	if (IsSanctionedSimpleUnitIdentifier(unit)) {
		return true;
	}
	const units = unit.split("-per-");
	if (units.length !== 2) {
		return false;
	}
	const [numerator, denominator] = units;
	if (!IsSanctionedSimpleUnitIdentifier(numerator) || !IsSanctionedSimpleUnitIdentifier(denominator)) {
		return false;
	}
	return true;
}