Updated ManyToOne::Proxy to delegate #class to parent

* Fixes issue with Merb resource() helper method not being able to
  figure out route using ManyToOne::Proxy object.

[#628 state:resolved]

lib/dm-core/associations/many_to_one.rb

@@ -48,7 +48,7 @@ def #{name}_association
       class Proxy
         include Assertions
 
-        instance_methods.each { |m| undef_method m unless %w[ __id__ __send__ class kind_of? respond_to? assert_kind_of should should_not instance_variable_set instance_variable_get ].include?(m) }
+        instance_methods.each { |m| undef_method m unless %w[ __id__ __send__ kind_of? respond_to? assert_kind_of should should_not instance_variable_set instance_variable_get ].include?(m.to_s) }
 
         def replace(parent)
           @parent = parent

lib/dm-core/associations/one_to_many.rb

@@ -72,7 +72,7 @@ def #{name}_association
       class Proxy
         include Assertions
 
-        instance_methods.each { |m| undef_method m unless %w[ __id__ __send__ class kind_of? respond_to? assert_kind_of should should_not instance_variable_set instance_variable_get ].include?(m) }
+        instance_methods.each { |m| undef_method m unless %w[ __id__ __send__ class kind_of? respond_to? assert_kind_of should should_not instance_variable_set instance_variable_get ].include?(m.to_s) }
 
         # FIXME: remove when RelationshipChain#get_children can return a Collection
         def all(query = {})

lib/dm-core/query.rb

@@ -573,7 +573,7 @@ def initialize(target, operator)
     class Path
       include Assertions
 
-   %w[ id type ].each { |m| undef_method m }
+      instance_methods.each { |m| undef_method m if %w[ id type ].include?(m.to_s) }
 
       attr_reader :relationships, :model, :property, :operator
 

spec/unit/associations/many_to_one_spec.rb

@@ -30,6 +30,13 @@ class Vehicle
     @association.should respond_to(:replace)
   end
 
+  describe '#class' do
+    it 'should be forwarded to parent' do
+      @parent.should_receive(:class).and_return(Manufacturer)
+      @association.class.should == Manufacturer
+    end
+  end
+
   describe '#replace' do
     before do
       @other = mock('other parent')