Merge 3b0f5a0 into 2e31a14

.gitignore

@@ -17,3 +17,5 @@ test/version_tmp
 tmp
 *.swp
 .ruby-version
+.ruby-gemset
+.idea

lib/active_model/serializer.rb

@@ -60,7 +60,7 @@ def serializer_for(resource)
         end
       end
 
-      attr_accessor :_root, :_attributes, :_associations
+      attr_accessor :_root, :_attributes, :_associations, :_serialize_all_attributes
       alias root  _root=
       alias root= _root=
 
@@ -71,6 +71,10 @@ def root_name
       def attributes(*attrs)
         @_attributes.concat attrs
 
+        if attrs.empty?
+          @_serialize_all_attributes = true
+        end
+
         attrs.each do |attr|
           define_method attr do
             object.read_attribute_for_serialization attr
@@ -121,10 +125,11 @@ def json_key
       end
     end
 
-    def attributes
-      filter(self.class._attributes.dup).each_with_object({}) do |name, hash|
+    def attributes(object=nil)
+      attribute_hash = filter(self.class._attributes.dup).each_with_object({}) do |name, hash|
         hash[name] = send(name)
       end
+      self.class._serialize_all_attributes && object && object.respond_to?(:attributes) ? object.attributes : attribute_hash
     end
 
     def associations
@@ -192,7 +197,7 @@ def serialize_ids(association)
 
     def serializable_object(options={})
       return @wrap_in_array ? [] : nil if @object.nil?
-      hash = attributes
+      hash = attributes(@object)
       hash.merge! associations
       @wrap_in_array ? [hash] : hash
     end

test/fixtures/poro.rb

@@ -25,6 +25,11 @@ def profile
 class Profile < Model
 end
 
+# Allows us to test ActiveRecord::Base-like attributes capability
+class ProfileWithAttributes < Profile
+  attr_accessor :attributes
+end
+
 class Post < Model
   def comments
     @comments ||= [Comment.new(content: 'C1'),
@@ -53,6 +58,13 @@ def description
   attributes :name, :description
 end
 
+class ProfileAllAttributesSerializer < ActiveModel::Serializer
+  attributes
+end
+
+class ProfileNoAttributesSerializer < ActiveModel::Serializer
+end
+
 class PostSerializer < ActiveModel::Serializer
   attributes :title, :body
 

test/unit/active_model/serializer/attributes_test.rb

@@ -13,6 +13,22 @@ def test_attributes_definition
                      @profile_serializer.class._attributes)
       end
 
+      def test_all_attributes_definition
+        initial_attributes = { name: 'Name 1', description: 'Description 1', comments: 'Comments 1' }
+        @profile_with_attributes = ProfileWithAttributes.new(initial_attributes)
+        @profile_all_attributes_serializer = ProfileAllAttributesSerializer.new(@profile_with_attributes)
+        serialized_attributes = @profile_all_attributes_serializer.as_json
+        assert_equal({"profile_all_attributes" => initial_attributes}, serialized_attributes)
+      end
+
+      def test_no_attributes_definition
+        initial_attributes = { name: 'Name 1', description: 'Description 1', comments: 'Comments 1' }
+        @profile_with_attributes = ProfileWithAttributes.new(initial_attributes)
+        @profile_no_attributes_serializer = ProfileNoAttributesSerializer.new(@profile_with_attributes)
+        serialized_attributes = @profile_no_attributes_serializer.as_json
+        assert_equal({"profile_no_attributes" => {}}, serialized_attributes)
+      end
+
       def test_attributes_serialization_using_serializable_hash
         assert_equal({
           name: 'Name 1', description: 'Description 1'