[MODEL] Refactored the if/elsif statement from 5fb9c56 into case

Related: elastic#369, elastic#370

Author: karmi

elasticsearch-model/lib/elasticsearch/model/adapters/multiple.rb

@@ -53,11 +53,12 @@ def __records_by_type
           def __records_for_klass(klass, ids)
             adapter = __adapter_for_klass(klass)
 
-            if Elasticsearch::Model::Adapter::ActiveRecord.equal?(adapter)
+            case
+              when Elasticsearch::Model::Adapter::ActiveRecord.equal?(adapter)
                 klass.where(klass.primary_key => ids)
-            elsif Elasticsearch::Model::Adapter::Mongoid.equal?(adapter)
+              when Elasticsearch::Model::Adapter::Mongoid.equal?(adapter)
                 klass.where(:id.in => ids)
-            else
+              else
                 klass.find(ids)
             end
           end

elasticsearch-model/test/integration/multiple_models_test.rb

@@ -88,6 +88,7 @@ class ::Series < ActiveRecord::Base
 
         should "only retrieve records for existing results" do
           ::Series.find_by_name("The greatest Series").delete
+          ::Series.__elasticsearch__.refresh_index!
           response = Elasticsearch::Model.search("\"The greatest Episode\"^2 OR \"The greatest Series\"", [Series, Episode])
 
           assert response.any?, "Response should not be empty: #{response.to_a.inspect}"