Implement has_one's embed ids include true

lib/active_model/serializer.rb

@@ -74,7 +74,8 @@ module ActiveModel
       self.class._associations.each_with_object({}) do |association, hash|
         if association.embed_ids?
           hash[association.key] = serialize_ids association
-        elsif association.embed_objects?
+        end
+        if association.embed_objects?
           associated_data = send(association.name)
           hash[association.embedded_key] = association.build_serializer(associated_data).serializable_hash
         end

lib/active_model/serializer/associations.rb

@@ -13,7 +13,8 @@ module ActiveModel
         @serializer_class = serializer.is_a?(String) ? serializer.constantize : serializer
       end
 
-      attr_reader :name, :embed_ids, :embed_objects, :embed_key, :include
+      attr_reader :name, :embed_ids, :embed_objects, :embed_key
+      attr_accessor :include
       alias embed_ids? embed_ids
       alias embed_objects? embed_objects
       alias include? include
@@ -23,6 +24,10 @@ module ActiveModel
         @embed_objects = embed == :object || embed == :objects
       end
 
+      def embed_objects?
+        @embed_objects || @embed_ids && @include
+      end
+
       def build_serializer(object)
         @serializer_class ||= Serializer.serializer_for(object)
 

test/unit/active_model/serializer/has_one_test.rb

@@ -7,6 +7,8 @@ module ActiveModel
       def setup
         @model = ::Model.new({ :attr1 => 'value1', :attr2 => 'value2', :attr3 => 'value3' })
         @model_serializer = AnotherSerializer.new(@model)
+        @model_serializer.class._associations[0].include = false
+        @model_serializer.class._associations[0].embed = :ids
       end
 
       def test_associations_definition
@@ -18,14 +20,12 @@ module ActiveModel
       end
 
       def test_associations_embedding_ids_serialization_using_serializable_hash
-        @model_serializer.class._associations[0].embed = :ids
         assert_equal({
           'attr2' => 'value2', 'attr3' => 'value3', 'model_id' => @model.model.object_id
         }, @model_serializer.serializable_hash)
       end
 
       def test_associations_embedding_ids_serialization_using_as_json
-        @model_serializer.class._associations[0].embed = :ids
         assert_equal({
           'attr2' => 'value2', 'attr3' => 'value3', 'model_id' => @model.model.object_id
         }, @model_serializer.as_json)
@@ -44,6 +44,20 @@ module ActiveModel
           'attr2' => 'value2', 'attr3' => 'value3', 'model' => { 'attr1' => 'v1', 'attr2' => 'v2' }
         }, @model_serializer.as_json)
       end
+
+      def test_associations_embedding_ids_including_objects_serialization_using_serializable_hash
+        @model_serializer.class._associations[0].include = true
+        assert_equal({
+          'attr2' => 'value2', 'attr3' => 'value3', 'model_id' => @model.model.object_id, 'model' => { 'attr1' => 'v1', 'attr2' => 'v2' }
+        }, @model_serializer.serializable_hash)
+      end
+
+      def test_associations_embedding_ids_including_objects_serialization_using_as_json
+        @model_serializer.class._associations[0].include = true
+        assert_equal({
+          'attr2' => 'value2', 'attr3' => 'value3', 'model_id' => @model.model.object_id, 'model' => { 'attr1' => 'v1', 'attr2' => 'v2' }
+        }, @model_serializer.as_json)
+      end
     end
   end
 end