Adding methods with a generic name to a core Ruby class (and therefore

all instances of that class) is not a good idea.

Crack was defining [1] `attributes` accessor methods on the core Ruby
`String` class which in turn caused a very difficult to track down bug
when using Mongoid, because of this [2]. This commit changes Crack so it
just defines the `attributes` accessor methods on the relevant instances
of `String`.

[1] https://github.com/jnunemaker/crack/blob/master/lib/crack/xml.rb#L85
[2] https://github.com/mongoid/mongoid/blob/master/lib/mongoid/relations/builder.rb#L38

Created by floehopper

lib/nori/xml_utility_node.rb

@@ -83,8 +83,12 @@ class << f
 
       if @text
         t = typecast_value( unnormalize_xml_entities( inner_html ) )
-        t.class.send(:attr_accessor, :attributes)
-        t.attributes = attributes
+        if t.is_a?(String)
+          class << t
+            attr_accessor :attributes
+          end
+          t.attributes = attributes
+        end
         return { name => t }
       else
         #change repeating groups into an array

spec/nori/nori_spec.rb

@@ -104,6 +104,16 @@
         it "default attributes to empty hash if not present" do
           @data['opt']['user'][1].attributes.should == {}
         end
+
+        it "add 'attributes' accessor methods to parsed instances of String" do
+          @data['opt']['user'][0].should respond_to(:attributes)
+          @data['opt']['user'][0].should respond_to(:attributes=)
+        end
+
+        it "not add 'attributes' accessor methods to all instances of String" do
+          "some-string".should_not respond_to(:attributes)
+          "some-string".should_not respond_to(:attributes=)
+        end
       end
 
       it "should typecast an integer" do