func addColumns()

in pkg/printers/tableprinter.go [244:302]
45 lines of code
12 McCabe index (conditional complexity)

func addColumns(pos columnAddPosition, table *metav1.Table, columns []metav1.TableColumnDefinition, valueFuncs []cellValueFunc) error {
	if len(columns) != len(valueFuncs) {
		return fmt.Errorf("cannot prepend columns, unmatched value functions")
	}
	if len(columns) == 0 {
		return nil
	}

	// Compute the new rows
	newRows := make([][]interface{}, len(table.Rows))
	for i := range table.Rows {
		newCells := make([]interface{}, 0, len(columns)+len(table.Rows[i].Cells))

		if pos == end {
			// If we're appending, start with the existing cells,
			// then add nil cells to match the number of columns
			newCells = append(newCells, table.Rows[i].Cells...)
			for len(newCells) < len(table.ColumnDefinitions) {
				newCells = append(newCells, nil)
			}
		}

		// Compute cells for new columns
		for _, f := range valueFuncs {
			newCell, err := f(table.Rows[i])
			if err != nil {
				return err
			}
			newCells = append(newCells, newCell)
		}

		if pos == beginning {
			// If we're prepending, add existing cells
			newCells = append(newCells, table.Rows[i].Cells...)
		}

		// Remember the new cells for this row
		newRows[i] = newCells
	}

	// All cells successfully computed, now replace columns and rows
	newColumns := make([]metav1.TableColumnDefinition, 0, len(columns)+len(table.ColumnDefinitions))
	switch pos {
	case beginning:
		newColumns = append(newColumns, columns...)
		newColumns = append(newColumns, table.ColumnDefinitions...)
	case end:
		newColumns = append(newColumns, table.ColumnDefinitions...)
		newColumns = append(newColumns, columns...)
	default:
		return fmt.Errorf("invalid column add position: %v", pos)
	}
	table.ColumnDefinitions = newColumns
	for i := range table.Rows {
		table.Rows[i].Cells = newRows[i]
	}

	return nil
}