_markDataTables()

in Readability.js [2281:2339]

• 46 lines of code
• 13 McCabe index (conditional complexity)

  _markDataTables(root) {
    var tables = root.getElementsByTagName("table");
    for (var i = 0; i < tables.length; i++) {
      var table = tables[i];
      var role = table.getAttribute("role");
      if (role == "presentation") {
        table._readabilityDataTable = false;
        continue;
      }
      var datatable = table.getAttribute("datatable");
      if (datatable == "0") {
        table._readabilityDataTable = false;
        continue;
      }
      var summary = table.getAttribute("summary");
      if (summary) {
        table._readabilityDataTable = true;
        continue;
      }

      var caption = table.getElementsByTagName("caption")[0];
      if (caption && caption.childNodes.length) {
        table._readabilityDataTable = true;
        continue;
      }

      // If the table has a descendant with any of these tags, consider a data table:
      var dataTableDescendants = ["col", "colgroup", "tfoot", "thead", "th"];
      var descendantExists = function (tag) {
        return !!table.getElementsByTagName(tag)[0];
      };
      if (dataTableDescendants.some(descendantExists)) {
        this.log("Data table because found data-y descendant");
        table._readabilityDataTable = true;
        continue;
      }

      // Nested tables indicate a layout table:
      if (table.getElementsByTagName("table")[0]) {
        table._readabilityDataTable = false;
        continue;
      }

      var sizeInfo = this._getRowAndColumnCount(table);

      if (sizeInfo.columns == 1 || sizeInfo.rows == 1) {
        // single colum/row tables are commonly used for page layout purposes.
        table._readabilityDataTable = false;
        continue;
      }

      if (sizeInfo.rows >= 10 || sizeInfo.columns > 4) {
        table._readabilityDataTable = true;
        continue;
      }
      // Now just go by size entirely:
      table._readabilityDataTable = sizeInfo.rows * sizeInfo.columns > 10;
    }
  },