lib/axlsx/drawing/series_title.rb in axlsx-2.0.1 vs lib/axlsx/drawing/series_title.rb in axlsx-2.1.0.pre

@@ -7,14 +7,14 @@
     # @param [String] str
     # @return [String]
     def to_xml_string(str = '')
       str << '<c:tx>'
       str << '<c:strRef>'
-      str << '<c:f>' << Axlsx::cell_range([@cell]) << '</c:f>'
+      str << ('<c:f>' << Axlsx::cell_range([@cell]) << '</c:f>')
       str << '<c:strCache>'
       str << '<c:ptCount val="1"/>'
       str << '<c:pt idx="0">'
-      str << '<c:v>' << @text << '</c:v>'
+      str << ('<c:v>' << @text << '</c:v>')
       str << '</c:pt>'
       str << '</c:strCache>'
       str << '</c:strRef>'
       str << '</c:tx>'
     end