4 files changed, 40 insertions, 12 deletions
diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index 38a761384e..4eccea2848 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,3 +1,8 @@
+*   Ensure classes which `include Enumerable` get `#to_json` in addition to
+    `#as_json`.
+
+    *Sammy Larbi*
+
 *   Change the signature of `fetch_multi` to return a hash rather than an
     array. This makes it consistent with the output of `read_multi`.
 
diff --git a/activesupport/lib/active_support/core_ext/object/json.rb b/activesupport/lib/active_support/core_ext/object/json.rb
index 8e08cfbf26..5496692373 100644
--- a/activesupport/lib/active_support/core_ext/object/json.rb
+++ b/activesupport/lib/active_support/core_ext/object/json.rb
@@ -26,7 +26,7 @@ require 'active_support/core_ext/module/aliasing'
 # bypassed completely. This means that as_json won't be invoked and the JSON gem will simply
 # ignore any options it does not natively understand. This also means that ::JSON.{generate,dump}
 # should give exactly the same results with or without active support.
-[Object, Array, FalseClass, Float, Hash, Integer, NilClass, String, TrueClass].each do |klass|
+[Object, Array, FalseClass, Float, Hash, Integer, NilClass, String, TrueClass, Enumerable].each do |klass|
   klass.class_eval do
     def to_json_with_active_support_encoder(options = nil)
       if options.is_a?(::JSON::State)
diff --git a/activesupport/lib/active_support/core_ext/object/to_json.rb b/activesupport/lib/active_support/core_ext/object/to_json.rb
index 3dcae6fc7f..f58364f9c6 100644
--- a/activesupport/lib/active_support/core_ext/object/to_json.rb
+++ b/activesupport/lib/active_support/core_ext/object/to_json.rb
@@ -2,4 +2,4 @@ ActiveSupport::Deprecation.warn 'You have required `active_support/core_ext/obje
   'This file will be removed in Rails 4.2. You should require `active_support/core_ext/object/json` ' \
   'instead.'
 
-require 'active_support/core_ext/object/json'
+require 'active_support/core_ext/object/json'
+\ No newline at end of file
diff --git a/activesupport/test/json/encoding_test.rb b/activesupport/test/json/encoding_test.rb
index c4283ee79a..f22d7b8b02 100644
--- a/activesupport/test/json/encoding_test.rb
+++ b/activesupport/test/json/encoding_test.rb
@@ -327,12 +327,39 @@ class TestJSONEncoding < ActiveSupport::TestCase
     assert_equal(%([{"address":{"city":"London"}},{"address":{"city":"Paris"}}]), json)
   end
 
-  def test_enumerable_should_pass_encoding_options_to_children_in_as_json
-    people = [
-      { :name => 'John', :address => { :city => 'London', :country => 'UK' }},
-      { :name => 'Jean', :address => { :city => 'Paris' , :country => 'France' }}
+  People = Class.new(BasicObject) do
+    include Enumerable
+    def initialize()
+      @people = [
+        { :name => 'John', :address => { :city => 'London', :country => 'UK' }},
+        { :name => 'Jean', :address => { :city => 'Paris' , :country => 'France' }}
+      ]
+    end
+    def each(*, &blk)
+      @people.each do |p|
+        yield p if blk
+        p
+      end.each
+    end
+  end
+
+  def test_enumerable_should_generate_json_with_as_json
+    json = People.new.as_json :only => [:address, :city]
+    expected = [
+      { 'address' => { 'city' => 'London' }},
+      { 'address' => { 'city' => 'Paris' }}
     ]
-    json = people.each.as_json :only => [:address, :city]
+
+    assert_equal(expected, json)
+  end
+
+  def test_enumerable_should_generate_json_with_to_json
+    json = People.new.to_json :only => [:address, :city]
+    assert_equal(%([{"address":{"city":"London"}},{"address":{"city":"Paris"}}]), json)
+  end
+
+  def test_enumerable_should_pass_encoding_options_to_children_in_as_json
+    json = People.new.each.as_json :only => [:address, :city]
     expected = [
       { 'address' => { 'city' => 'London' }},
       { 'address' => { 'city' => 'Paris' }}
@@ -342,11 +369,7 @@ class TestJSONEncoding < ActiveSupport::TestCase
   end
 
   def test_enumerable_should_pass_encoding_options_to_children_in_to_json
-    people = [
-      { :name => 'John', :address => { :city => 'London', :country => 'UK' }},
-      { :name => 'Jean', :address => { :city => 'Paris' , :country => 'France' }}
-    ]
-    json = people.each.to_json :only => [:address, :city]
+    json = People.new.each.to_json :only => [:address, :city]
 
     assert_equal(%([{"address":{"city":"London"}},{"address":{"city":"Paris"}}]), json)
   end