1 files changed, 23 insertions, 0 deletions
diff --git a/actionpack/test/controller/render_json_test.rb b/actionpack/test/controller/render_json_test.rb
index 5958b18d80..fc604a2db3 100644
--- a/actionpack/test/controller/render_json_test.rb
+++ b/actionpack/test/controller/render_json_test.rb
@@ -9,6 +9,10 @@ class RenderJsonTest < ActionController::TestCase
       hash.except!(*options[:except]) if options[:except]
       hash
     end
+
+    def to_json(options = {})
+      super :except => [:c, :e]
+    end
   end
 
   class TestController < ActionController::Base
@@ -22,6 +26,10 @@ class RenderJsonTest < ActionController::TestCase
       render :json => nil
     end
 
+    def render_json_render_to_string
+      render :text => render_to_string(:json => '[]')
+    end
+
     def render_json_hello_world
       render :json => ActiveSupport::JSON.encode(:hello => 'world')
     end
@@ -49,6 +57,10 @@ class RenderJsonTest < ActionController::TestCase
     def render_json_with_extra_options
       render :json => JsonRenderable.new, :except => [:c, :e]
     end
+
+    def render_json_without_options
+      render :json => JsonRenderable.new
+    end
   end
 
   tests TestController
@@ -68,6 +80,12 @@ class RenderJsonTest < ActionController::TestCase
     assert_equal 'application/json', @response.content_type
   end
 
+  def test_render_json_render_to_string
+    get :render_json_render_to_string
+    assert_equal '[]', @response.body
+  end
+
+
   def test_render_json
     get :render_json_hello_world
     assert_equal '{"hello":"world"}', @response.body
@@ -109,4 +127,9 @@ class RenderJsonTest < ActionController::TestCase
     assert_equal '{"a":"b"}', @response.body
     assert_equal 'application/json', @response.content_type
   end
+
+  def test_render_json_calls_to_json_from_object
+    get :render_json_without_options
+    assert_equal '{"a":"b"}', @response.body
+  end
 end