code: function (dataIndex) {
          var params = SeriesModel.prototype.getDataParams.apply(this, arguments);
  
          var node = this.getData().tree.getNodeByDataIndex(dataIndex);
          params.treePathInfo = wrapTreePathInfo(node, this);
  
          return params;
      }
docs: Add tree path to tooltip param
  
  @override
  @param {number} dataIndex
  @return {Object}