code: function record(depend, level) {
      if (!depend) {
        return;
      }
      depend.split(/\s*,\s*/).forEach(function (name) {
        var item = fnNodes[name];
        if (!item) {
          return;
        }
        var node = item.node;
        if (node.pending) {
          console.error(colors.red('A circular reference. name = %j'), name);
          return;
        }
        if (!fns[name]) {
          list.push(fnNodes[name]);
        }
        fns[name] = fnNodes[name];
        fns[name].require += level;
        node.pending = true;
        record(node.attrs.depend, level + 1);
        node.pending = false;
      });
    }
docs: 记录依赖关系
  
  @param {string} depend 依赖列表