ValueObject #clone and #dup return self

lib/virtus/value_object.rb

@@ -53,6 +53,16 @@ def initialize(attributes = {})
       def with(attribute_updates)
         self.class.new(get_attributes(&FILTER_NONE).merge(attribute_updates))
       end
+
+      # ValueObjects are immutable and can't be cloned. They always represent the same value.
+      #
+      # @return [self]
+      #
+      # @api public
+      def clone
+        self
+      end
+      alias dup clone
     end
 
     module ClassMethods

spec/integration/default_values_spec.rb

@@ -53,7 +53,7 @@ def default_editor_title
     it 'should not duplicate the ValueObject' do
       page1 = Examples::Page.new
       page2 = Examples::Page.new
-      page1.reference.object_id.should == page2.reference.object_id
+      page1.reference.should equal(page2.reference)
     end
   end
 

spec/unit/virtus/value_object/instance_methods/duplicates_spec.rb

@@ -0,0 +1,22 @@
+require 'spec_helper'
+
+describe Virtus::ValueObject::InstanceMethods, 'duplication' do
+  let(:described_class) do
+    Class.new do
+      include Virtus::ValueObject
+
+      attribute :name, String
+    end
+  end
+
+  subject { described_class.new }
+
+  it '#clone returns the same instance' do
+    subject.should equal(subject.clone)
+  end
+
+  it '#dup returns the same instance' do
+    subject.should equal(subject.dup)
+  end
+
+end