moment/src/lib/locale/formats.js

Parse, validate, manipulate, and display dates

import { formattingTokens } from '../format/format';

export var defaultLongDateFormat = {
    LTS: 'h:mm:ss A',
    LT: 'h:mm A',
    L: 'MM/DD/YYYY',
    LL: 'MMMM D, YYYY',
    LLL: 'MMMM D, YYYY h:mm A',
    LLLL: 'dddd, MMMM D, YYYY h:mm A',
};

export function longDateFormat(key) {
    var format = this._longDateFormat[key],
        formatUpper = this._longDateFormat[key.toUpperCase()],
        formatCache = this._longDateFormatCache;

    if (format || !formatUpper) {
        return format;
    }

    if (
        formatCache &&
        formatCache[key] &&
        formatCache[key].formatUpper === formatUpper
    ) {
        return formatCache[key].format;
    }

    format = formatUpper
        .match(formattingTokens)
        .map(function (tok) {
            if (
                tok === 'MMMM' ||
                tok === 'MM' ||
                tok === 'DD' ||
                tok === 'dddd'
            ) {
                return tok.slice(1);
            }
            return tok;
        })
        .join('');

    if (!formatCache) {
        formatCache = this._longDateFormatCache = {};
    }
    formatCache[key] = {
        formatUpper: formatUpper,
        format: format,
    };
    return format;
}