lion/packages/ui/components/localize/date/getMonthNames.js
2022-10-31 16:55:07 +01:00

37 lines
1.2 KiB
JavaScript

import { normalizeIntlDate } from './utils/normalizeIntlDate.js';
import { forceShortMonthNamesForEnGb } from './utils/forceShortMonthNamesForEnGb.js';
/** @type {Object.<string, Object.<string,string[]>>} */
const monthsLocaleCache = {};
/**
* @desc Returns month names for locale
* @param {Object} [options]
* @param {string} [options.locale] locale
* @param {"long" | "numeric" | "2-digit" | "short" | "narrow"} [options.style=long] long, short or narrow
* @returns {string[]} like: ['January', 'February', ...etc].
*/
export function getMonthNames({ locale = 'en-GB', style = 'long' } = {}) {
let months = monthsLocaleCache[locale] && monthsLocaleCache[locale][style];
if (months) {
return months;
}
months = [];
const formatter = new Intl.DateTimeFormat(locale, { month: style });
for (let i = 0; i < 12; i += 1) {
const date = new Date(2019, i, 1);
const formattedDate = formatter.format(date);
const normalizedDate = normalizeIntlDate(formattedDate);
months.push(normalizedDate);
}
if (locale === 'en-GB' && style === 'short') {
months = forceShortMonthNamesForEnGb(months);
}
monthsLocaleCache[locale] = monthsLocaleCache[locale] || {};
monthsLocaleCache[locale][style] = months;
return months;
}