code: function handleTree(username, repos, branch, tree, download) {
      let filterList = tree.filter(item => {
          return item.type === 'blob';
      })
      if (download !== '') {
          filterList = filterList.filter(item => {
              // create reg
              const downRepl = download.replace(/\//g, '\\\/').replace(/\./g, '\\\.');
              const reg = new RegExp(`^${downRepl}`)
              return reg.test(item.path);
          })
      }
      // request list is ready
      spinner.stop();
      bar = new ProgressBar(':bar :current/:total', {
          total: filterList.length
      });
  
      filterList.map(item => {
          downloadFile(username, repos, branch, item.path)
      });
  }
docs: parse response
  @param {String} username
  @param {String} repos
  @param {String} branch
  @param {String} tree
  @param {String} download