From 55647286da76950a77955317d74f4b97901f9530 Mon Sep 17 00:00:00 2001
From: Yehuda Katz <wycats@gmail.com>
Date: Wed, 11 Jan 2012 21:30:10 -0700
Subject: [PATCH] Make it possible to supply default serializer options in a
 controller.

---
 lib/action_controller/serialization.rb |  8 ++++++++
 test/serialization_test.rb             | 16 +++++++++++++++-
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/lib/action_controller/serialization.rb b/lib/action_controller/serialization.rb
index 583309fa..7c81a231 100644
--- a/lib/action_controller/serialization.rb
+++ b/lib/action_controller/serialization.rb
@@ -36,6 +36,9 @@ module ActionController
       send(_serialization_scope)
     end
 
+    def default_serializer_options
+    end
+
     def _render_option_json(json, options)
       if json.respond_to?(:to_ary)
         options[:root] ||= controller_name
@@ -43,6 +46,11 @@ module ActionController
 
       if json.respond_to?(:active_model_serializer) && (serializer = json.active_model_serializer)
         options[:scope] = serialization_scope
+
+        if default_options = default_serializer_options
+          options = options.merge(default_options)
+        end
+
         json = serializer.new(json, options)
       end
       super
diff --git a/test/serialization_test.rb b/test/serialization_test.rb
index e930f476..4032774f 100644
--- a/test/serialization_test.rb
+++ b/test/serialization_test.rb
@@ -22,6 +22,7 @@ class RenderJsonTest < ActionController::TestCase
     def as_json(*)
       hash = { :object => serializable_hash, :scope => @options[:scope].as_json }
       hash.merge!(:options => true) if @options[:options]
+      hash.merge!(:check_defaults => true) if @options[:check_defaults]
       hash
     end
 
@@ -109,6 +110,13 @@ class RenderJsonTest < ActionController::TestCase
       @current_user = Struct.new(:as_json).new(:current_user => true)
       render :json => JsonSerializable.new(true)
     end
+
+  private
+    def default_serializer_options
+      if params[:check_defaults]
+        { :check_defaults => true }
+      end
+    end
   end
 
   tests TestController
@@ -133,7 +141,6 @@ class RenderJsonTest < ActionController::TestCase
     assert_equal '[]', @response.body
   end
 
-
   def test_render_json
     get :render_json_hello_world
     assert_equal '{"hello":"world"}', @response.body
@@ -181,6 +188,13 @@ class RenderJsonTest < ActionController::TestCase
     assert_match '"object":{"serializable_object":true}', @response.body
   end
 
+  def test_render_json_with_serializer
+    get :render_json_with_serializer, :check_defaults => true
+    assert_match '"scope":{"current_user":true}', @response.body
+    assert_match '"object":{"serializable_object":true}', @response.body
+    assert_match '"check_defaults":true', @response.body
+  end
+
   def test_render_json_with_serializer_and_implicit_root
     get :render_json_with_serializer_and_implicit_root
     assert_match '"test":[{"serializable_object":true}]', @response.body