docs: function getDatasetModel(seriesModel) {
      var option = seriesModel.option;
      // Caution: consider the scenario:
      // A dataset is declared and a series is not expected to use the dataset,
      // and at the beginning `setOption({series: { noData })` (just prepare other
      // option but no data), then `setOption({series: {data: [...]}); In this case,
      // the user should set an empty array to avoid that dataset is used by default.
      var thisData = option.data;
      if (!thisData) {
          return seriesModel.ecModel.getComponent('dataset', option.datasetIndex || 0);
      }
  }