function mergeSortTables()

in frontend/app/components/chart/table_utils.ts [201:287]
79 lines of code
19 McCabe index (conditional complexity)

function mergeSortTables(
    diffTable: google.visualization.DataTable,
    oldTable: google.visualization.DataTable,
    newTable: google.visualization.DataTable, referenceCol: number,
    comparisonCol: number, formatDiffInfo: FormatDiffInfo[],
    formatValueInfo: FormatValueInfo[]): number {
  oldTable.sort({column: referenceCol, desc: false});  // Ascending order.
  newTable.sort({column: referenceCol, desc: false});  // Ascending order.
  const oldSize = oldTable.getNumberOfRows();
  const newSize = newTable.getNumberOfRows();
  // colsCount is number of columns in the original tables. In diffTable
  // there is one additional column at the end which is the difference
  // in self time between two stats.  The column is used solely for
  // sorting the diffTable and gets hidden before function returns.
  const colsCount = oldTable.getNumberOfColumns();
  const largeCharInASCII = '~~~~';
  let rowIndex = 0;
  for (let oldRow = 0, newRow = 0; oldRow < oldSize || newRow < newSize;
       rowIndex++) {
    // Assign the largest character in ASCII table for comparison.
    const oldReferenceValue = (oldRow < oldSize) ?
        oldTable.getValue(oldRow, referenceCol) :
        largeCharInASCII;
    const newReferenceValue = (newRow < newSize) ?
        newTable.getValue(newRow, referenceCol) :
        largeCharInASCII;
    if (oldRow < oldSize && newRow < newSize &&
        oldReferenceValue === newReferenceValue) {
      // If reference value is the same, then diff the two stats.
      for (let colIndex = 0; colIndex < colsCount; colIndex++) {
        if (colIndex !== 0 && oldTable.getColumnType(colIndex) === 'number') {
          const baseVal = oldTable.getValue(oldRow, colIndex);
          const diffVal = newTable.getValue(newRow, colIndex) -
              oldTable.getValue(oldRow, colIndex);
          diffTable.setCell(
              rowIndex, colIndex,
              formatValue(baseVal, colIndex, formatValueInfo) +
                  formatDiff(diffVal, baseVal, colIndex, formatDiffInfo));
        } else {  // Use oldTable's string values, or rank.
          diffTable.setCell(
              rowIndex, colIndex, oldTable.getValue(oldRow, colIndex));
        }
      }
      const diffValue = newTable.getValue(newRow, comparisonCol) -
          oldTable.getValue(oldRow, comparisonCol);
      diffTable.setCell(rowIndex, colsCount, diffValue);
      oldRow++, newRow++;
    } else if (newRow === newSize || oldReferenceValue < newReferenceValue) {
      // If only old stats, then assign the diff as negative old stats.
      for (let colIndex = 0; colIndex < colsCount; colIndex++) {
        if (colIndex !== 0 && oldTable.getColumnType(colIndex) === 'number') {
          const baseVal = oldTable.getValue(oldRow, colIndex);
          const diffVal = -oldTable.getValue(oldRow, colIndex);
          diffTable.setCell(
              rowIndex, colIndex,
              formatValue(baseVal, colIndex, formatValueInfo) +
                  formatDiff(diffVal, baseVal, colIndex, formatDiffInfo));
        } else {  // Use oldTable's string values, or rank.
          diffTable.setCell(
              rowIndex, colIndex, oldTable.getValue(oldRow, colIndex));
        }
      }
      const diffValue = -oldTable.getValue(oldRow, comparisonCol);
      diffTable.setCell(rowIndex, colsCount, diffValue);
      oldRow++;
    } else {  // if (oldRow == oldSize || oldReferenceValue > newReferenceValue)
      // If only new stats, then assign the diff as new stats.
      for (let colIndex = 0; colIndex < colsCount; colIndex++) {
        if (colIndex !== 0 && newTable.getColumnType(colIndex) === 'number') {
          const baseVal = 0;
          const diffVal = newTable.getValue(newRow, colIndex);
          diffTable.setCell(
              rowIndex, colIndex,
              formatValue(baseVal, colIndex, formatValueInfo) +
                  formatDiff(diffVal, baseVal, colIndex, formatDiffInfo));
        } else {  // Use newTable's string values, or rank.
          diffTable.setCell(
              rowIndex, colIndex, newTable.getValue(newRow, colIndex));
        }
      }
      const diffValue = newTable.getValue(newRow, comparisonCol);
      diffTable.setCell(rowIndex, colsCount, diffValue);
      newRow++;
    }  // End of if condition comparing opName.
  }    // End of for loop over all rows.
  return rowIndex;
}