M: parseIso()

in charts/shared/moment.js [3492:3578]
65 lines of code
17 McCabe index (conditional complexity)

            M: parseIso(match[3], sign),
            w: parseIso(match[4], sign),
            d: parseIso(match[5], sign),
            h: parseIso(match[6], sign),
            m: parseIso(match[7], sign),
            s: parseIso(match[8], sign),
        };
    } else if (duration == null) {
        // checks for null or undefined
        duration = {};
    } else if (
        typeof duration === 'object' &&
        ('from' in duration || 'to' in duration)
    ) {
        diffRes = momentsDifference(
            createLocal(duration.from),
            createLocal(duration.to)
        );

        duration = {};
        duration.ms = diffRes.milliseconds;
        duration.M = diffRes.months;
    }

    ret = new Duration(duration);

    if (isDuration(input) && hasOwnProp(input, '_locale')) {
        ret._locale = input._locale;
    }

    if (isDuration(input) && hasOwnProp(input, '_isValid')) {
        ret._isValid = input._isValid;
    }

    return ret;
}

createDuration.fn = Duration.prototype;
createDuration.invalid = createInvalid$1;

function parseIso(inp, sign) {
    // We'd normally use ~~inp for this, but unfortunately it also
    // converts floats to ints.
    // inp may be undefined, so careful calling replace on it.
    var res = inp && parseFloat(inp.replace(',', '.'));
    // apply sign while we're at it
    return (isNaN(res) ? 0 : res) * sign;
}

function positiveMomentsDifference(base, other) {
    var res = {};

    res.months =
        other.month() - base.month() + (other.year() - base.year()) * 12;
    if (base.clone().add(res.months, 'M').isAfter(other)) {
        --res.months;
    }

    res.milliseconds = +other - +base.clone().add(res.months, 'M');

    return res;
}

function momentsDifference(base, other) {
    var res;
    if (!(base.isValid() && other.isValid())) {
        return { milliseconds: 0, months: 0 };
    }

    other = cloneWithOffset(other, base);
    if (base.isBefore(other)) {
        res = positiveMomentsDifference(base, other);
    } else {
        res = positiveMomentsDifference(other, base);
        res.milliseconds = -res.milliseconds;
        res.months = -res.months;
    }

    return res;
}

// TODO: remove 'name' arg after deprecation is removed
function createAdder(direction, name) {
    return function (val, period) {
        var dur, tmp;
        //invert the arguments, but complain about it
        if (period !== null && !isNaN(+period)) {