function configFromISO()

in ui/src/main/resources/static/moment/moment-2.26.js [2345:2399]
52 lines of code
17 McCabe index (conditional complexity)

function configFromISO(config) {
    var i,
        l,
        string = config._i,
        match = extendedIsoRegex.exec(string) || basicIsoRegex.exec(string),
        allowTime,
        dateFormat,
        timeFormat,
        tzFormat;

    if (match) {
        getParsingFlags(config).iso = true;

        for (i = 0, l = isoDates.length; i < l; i++) {
            if (isoDates[i][1].exec(match[1])) {
                dateFormat = isoDates[i][0];
                allowTime = isoDates[i][2] !== false;
                break;
            }
        }
        if (dateFormat == null) {
            config._isValid = false;
            return;
        }
        if (match[3]) {
            for (i = 0, l = isoTimes.length; i < l; i++) {
                if (isoTimes[i][1].exec(match[3])) {
                    // match[2] should be 'T' or space
                    timeFormat = (match[2] || ' ') + isoTimes[i][0];
                    break;
                }
            }
            if (timeFormat == null) {
                config._isValid = false;
                return;
            }
        }
        if (!allowTime && timeFormat != null) {
            config._isValid = false;
            return;
        }
        if (match[4]) {
            if (tzRegex.exec(match[4])) {
                tzFormat = 'Z';
            } else {
                config._isValid = false;
                return;
            }
        }
        config._f = dateFormat + (timeFormat || '') + (tzFormat || '');
        configFromStringAndFormat(config);
    } else {
        config._isValid = false;
    }
}