Function addSubtract$1

tests/test_code/js/moment/moment.js:5189–5197

(duration, input, value, direction)

    }

    function addSubtract$1(duration, input, value, direction) {
        var other = createDuration(input, value);

        duration._milliseconds += direction * other._milliseconds;
        duration._days += direction * other._days;
        duration._months += direction * other._months;

        return duration._bubble();
    }

    // supports only 2.0-style add(1, 's') or add(duration)
    function add$1(input, value) {