lib/rbbt/tsv/manipulate.rb in rbbt-util-5.5.50 vs lib/rbbt/tsv/manipulate.rb in rbbt-util-5.5.51

@@ -247,15 +247,22 @@
         else
           case type 
           when :double
             new_key_field_name, new_field_names = through new_key_field, new_fields, uniq, zipped do |key, value|
               if data[key].nil?
-                #data[key] = value.collect{|v| v.dup}
-                data[key] = value.collect{|v| v.dup}
+                #data[key] = value.collect{|v| v.nil? ? nil : v.dup}
+                data[key] = value.dup
               else
-                current = data[key]
-                value.each_with_index do |v, i|
-                  current[i].concat v
+                if current = data[key] 
+                  value.each_with_index do |v, i|
+                    if _c = current[i]
+                      _c.concat v if v
+                    else
+                      current[i] = v || []
+                    end
+                  end
+                else
+                  current = v.collect{|e| [e] }
                 end
                 data[key] = current if data.respond_to? :tokyocabinet_class
               end
             end
           when :flat