utility.rb in write_xlsx-0.85.2

- old
+ new

@@ -257,13 +257,13 @@
     # Ex: ("A4", "Hello") is converted to (3, 0, "Hello").
     #
     def substitute_cellref(cell, *args)       #:nodoc:
       return [*args] if cell.respond_to?(:coerce) # Numeric
 
-      cell.upcase!
+      normalized_cell = cell.upcase
 
-      case cell
+      case normalized_cell
       # Convert a column range: 'A:A' or 'B:G'.
       # A range such as A:A is equivalent to A1:65536, so add rows as required
       when /\$?([A-Z]{1,3}):\$?([A-Z]{1,3})/
         row1, col1 =  xl_cell_to_rowcol($1 + '1')
         row2, col2 =  xl_cell_to_rowcol($2 + ROW_MAX.to_s)
@@ -276,10 +276,10 @@
       # Convert a cell reference: 'A1' or 'AD2000'
       when /\$?([A-Z]{1,3}\$?\d+)/
         row1, col1 =  xl_cell_to_rowcol($1)
         return [row1, col1, *args]
       else
-        raise("Unknown cell reference #{cell}")
+        raise("Unknown cell reference #{normalized_cell}")
       end
     end
 
     def underline_attributes(underline)
       if underline == 2