code: function getTags(html) {
          const closed = html.match(new RegExp(`<${options.tagName}(.*)/${options.tagName}>`, 'g')) || [];
          const selfClosed = html.match(new RegExp(`<${options.tagName}(.*?)\/>`, 'g')) || [];
  
          return [].concat(closed, selfClosed);
      }
docs: Matches <tagName></tagName> and <tagName />
  
  @param {String} html - stringified file content
  @returns {Array.<String>}