Add serializers

lib/draper.rb

@@ -1,5 +1,8 @@
 require 'action_view'
+require 'active_model/naming'
 require 'active_model/serialization'
+require 'active_model/serializers/json'
+require 'active_model/serializers/xml'
 require 'active_support/inflector'
 require 'active_support/core_ext/hash/keys'
 require 'active_support/core_ext/hash/reverse_merge'

lib/draper/decorator.rb

@@ -2,7 +2,10 @@ module Draper
   class Decorator
     include Draper::ViewHelpers
     extend Draper::Delegation
+
     include ActiveModel::Serialization
+    include ActiveModel::Serializers::JSON
+    include ActiveModel::Serializers::Xml
 
     # @return the object being decorated.
     attr_reader :source

spec/dummy/spec/decorators/post_decorator_spec.rb

@@ -40,6 +40,17 @@ describe PostDecorator do
     expect(decorator.serializable_hash["updated_at"]).to be :overridden
   end
 
+  it "serializes to JSON" do
+    json = decorator.to_json
+    expect(json).to match /^{"post":{.+}}$/
+    expect(json).to match /"updated_at":"overridden"/
+  end
+
+  it "serializes to XML" do
+    xml = Capybara.string(decorator.to_xml)
+    expect(xml).to have_css "post > updated-at", text: "overridden"
+  end
+
   it "uses a test view context from ApplicationController" do
     expect(Draper::ViewContext.current.controller).to be_an ApplicationController
   end