shelving/util/currency.js

Toolkit for using data in JavaScript.

import { RequiredError } from "../error/RequiredError.js";
/** Array of all supported currency codes in this runtime. */
export const CURRENCY_CODES = Intl.supportedValuesOf("currency");
/**
 * Require that a value is a valid ISO 4217 currency code, and return it as a `Currency` type.
 */
export function getCurrencyCode(value) {
    const currency = value.toUpperCase().trim();
    return CURRENCY_CODES.includes(currency) ? currency : undefined;
}
/**
 * Require that a value is a valid ISO 4217 currency code, and return it as a `Currency` type.
 */
export function requireCurrencyCode(value, caller = requireCurrencyCode) {
    const currency = getCurrencyCode(value);
    if (!currency)
        throw new RequiredError("Unknown currency code", { received: value, caller });
    return currency;
}
function _formatter(currency, caller) {
    return new Intl.NumberFormat(undefined, {
        style: "currency",
        currency: requireCurrencyCode(currency, caller),
        currencyDisplay: "narrowSymbol",
    });
}
const _isCurrencyNumberPart = ({ type }) => type === "currency";
/**
 * Get the display symbol used for a currency.
 *
 * @throws {RequiredError} If the currency code is malformed or unsupported.
 *
 * @example getCurrencySymbol("GBP"); // "£"
 */
export function getCurrencySymbol(currency, caller = getCurrencySymbol) {
    return _formatter(currency, caller).formatToParts(0).find(_isCurrencyNumberPart)?.value;
}
/**
 * Get the "step" value for a currency, i.e. the smallest fractional unit that is used for that currency.
 * - E.g. `0.01` for USD, `0.001` for some cryptocurrencies, and `1` for JPY.
 * @throws {RequiredError} If the currency code is malformed or unsupported.
 */
export function getCurrencyStep(currency, caller = getCurrencyStep) {
    const { minimumFractionDigits = 0 } = _formatter(currency, caller).resolvedOptions();
    return 1 / 10 ** minimumFractionDigits;
}