code: function Seeker(cron, now) {
    if (cron.parts === null) {
      throw new Error('No schedule found');
    }
    var date;
    if (cron.options.timezone) {
      date = moment.tz(now, cron.options.timezone);
    } else {
      date = moment(now);
    }
    if (!date.isValid()) {
      throw new Error('Invalid date provided');
    }
    if (date.seconds() > 0) {
      // Add a minute to the date to prevent returning dates in the past
      date.add(1, 'minute');
    }
    this.cron = cron;
    this.now = date;
    this.date = date;
    this.pristine = true;
  }
docs: Creates an instance of Seeker.
  Seeker objects search for execution times of a cron schedule.
  
  @constructor
  @this {Seeker}