Partial update behavior

elasticsearch-model/lib/elasticsearch/model/indexing.rb

@@ -336,7 +336,11 @@ def delete_document(options={})
         def update_document(options={})
           if changed_attributes = self.instance_variable_get(:@__changed_attributes)
             attributes = if respond_to?(:as_indexed_json)
-              changed_attributes.select { |k,v| self.as_indexed_json.keys.include? k }
+              json = self.as_indexed_json
+              changed_attributes.inject({}) do |memo,(key,value)|
+                memo[key] = json[key] if json.keys.include? key
+                memo
+              end
             else
               changed_attributes
             end

elasticsearch-model/test/unit/indexing_test.rb

@@ -295,6 +295,24 @@ def as_indexed_json(options={})
 
         instance.update_document
       end
+
+      should "get attributes from as_indexed_json during partial update" do
+        client   = mock('client')
+        instance = ::DummyIndexingModelWithCallbacksAndCustomAsIndexedJson.new
+
+        instance.instance_variable_set(:@__changed_attributes, {foo: {ru:'B'} })
+
+        client.expects(:update).with do |payload|
+          assert_equal({foo: 'B'}, payload[:body][:doc])
+        end
+
+        instance.expects(:client).returns(client)
+        instance.expects(:index_name).returns('foo')
+        instance.expects(:document_type).returns('bar')
+        instance.expects(:id).returns('1')
+
+        instance.update_document
+      end
     end
 
     context "Re-creating the index" do