code: function parseSelector(selector = '') {
    const tagMatch = selector.match(/^[a-zA-Z0-9='"[\]_-]*/g)
    const classNamesMatch = selector.match(/\.[a-zA-Z0-1_-]*/g)
  
    return {
      tag: tagMatch ? tagMatch[0] : undefined,
      classNames: classNamesMatch ? classNamesMatch.map(cname => cname.substr(1)) : []
    }
  }
docs: Parse tag and classNames from given selector, if any are specified
  
  @param  {?String} selector
  @return {Object}