Admit locales (es-ES, en-GB, etc.) to format the numbers

Current behavior

Currently is necessary to describe how to format numbers and currencies by hand (except some languages), which makes it more involved on apps with a lot of languages because it’s necessary to provide the configuration for each of them.

Expected behavior

There is a native Intl.NumberFormat object (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/NumberFormat) that supports the locales.

Those locales work quite well, although they aren’t as customizable as autoNumeric, and it’s not possible to use cryptocurrencies or custom currencies. The biggest advantage is that they are just ready to use on all browsers without coding anything.

It could work like this:

new AutoNumeric(domElement, { locale: 'ja-JP' });

The locale configuration could later be overridden by any of the autoNumeric options.

[ozum]

@AlexandreBonneau I submitted polished versions covering edge cases of above functions to npm and github. Please see intl-data source code.

You can use it or copy/paste it into your source code as you wish. I appreciate if you include my credits also.

[ozum]

@AlexandreBonneau please see above proposed solution. Also it could be a good idea to memoize values.

const localeOptionsCache = {};
const currencyCache = {};

/**
 * Returns group separators, decimal character, currency symbol placement, percent symbol and percent symbol placement for given locale.
 * @param {string} locale   - Locale to get options for.
 * @returns {Object}        - Group separators, decimal character, currency symbol, percent symbol and percent symbol placement.
 */
function getLocaleOptions(locale) {
  if (localeOptionsCache[locale] === undefined) {
    const [digitGroupSeparator, decimalCharacter] = (1111.1).toLocaleString(locale).replace(/1/g, "");
    const currencySymbolPlacement = (1).toLocaleString(locale, { style: "currency", currency: "USD" })[0] === "1" ? "s" : "p";
    localeOptionsCache[locale] = { digitGroupSeparator, decimalCharacter, currencySymbolPlacement };
    const percentString = (0.01).toLocaleString(locale, { style: "percent" });
    const percentSymbolPlacement = percentString[0] === "1" ? "s" : "p";
    const percentSymbol = percentString.replace("1", ""); // Some locales contains space, some not.
    localeOptionsCache[locale] = { digitGroupSeparator, decimalCharacter, currencySymbolPlacement, percentSymbolPlacement, percentSymbol };
  }
  return localeOptionsCache[locale];
}

/**
 * Returns currency symbol for given currency code.
 * @param {string} currencyCode - ISO currency code to get symbol for.
 * @returns {string}            - Currency symbol
 */
function getCurrencySign(currencyCode) {
  if (currencyCache[currencyCode] === undefined) {
    currencyCache[currencyCode] = (0).toLocaleString("tr-TR", { style: "currency", currency: currencyCode }).replace("0,00", "");
  }
  return currencyCache[currencyCode];
}