Fix equality to not use extend.

This can totally kill performance.

lib/draper/decoratable/equality.rb

@@ -9,6 +9,10 @@ module Draper
           other.respond_to?(:decorated?) && other.decorated? &&
           other.respond_to?(:source) && self == other.source
       end
+
+      def self.test(first, other)
+        first == other
+      end
     end
   end
 end

lib/draper/decorator.rb

@@ -163,7 +163,7 @@ module Draper
     #
     # @return [Boolean]
     def ==(other)
-      source.extend(Draper::Decoratable::Equality) == other
+      Draper::Decoratable::Equality.test(source, other)
     end
 
     # Checks if `self.kind_of?(klass)` or `source.kind_of?(klass)`

spec/draper/decorator_spec.rb

@@ -380,15 +380,6 @@ module Draper
     end
 
     describe "#==" do
-      it "ensures the source has a decoration-aware #==" do
-        source = Object.new
-        decorator = Decorator.new(source)
-
-        expect(source).not_to be_a_kind_of Draper::Decoratable::Equality
-        decorator == :something
-        expect(source).to be_a_kind_of Draper::Decoratable::Equality
-      end
-
       it "is true when source #== is true" do
         source = Model.new
         decorator = Decorator.new(source)