refactor the checking of the attributes of the record in IdentityMap#…

…add, so it's more readable

activerecord/lib/active_record/identity_map.rb

@@ -90,7 +90,7 @@ def get(klass, primary_key)
       end
 
       def add(record)
-        repository[record.class.symbolized_sti_name][record.id] = record if record.class.column_names - record.attribute_names == []
+        repository[record.class.symbolized_sti_name][record.id] = record if contain_all_columns(record)
       end
 
       def remove(record)
@@ -104,6 +104,12 @@ def remove_by_id(symbolized_sti_name, id)
       def clear
         repository.clear
       end
+
+      private
+
+        def contain_all_columns(record)
+          (record.class.column_names - record.attribute_names) == []
+        end
     end
 
     # Reinitialize an Identity Map model object from +coder+.

activerecord/test/cases/identity_map_test.rb

@@ -404,11 +404,12 @@ def test_find_using_identity_map_respects_readonly
     assert comment.save
   end
 
-  def test_do_not_add_to_identity_map_if_record_do_not_contain_all_columns
-    post = Post.select(:id).first
-    comment = post.comments[0]
+  def test_do_not_add_to_repository_if_record_does_not_contain_all_columns
+    author = Author.select(:id).first
+    post = author.posts.first
+
     assert_nothing_raised do
-      assert_not_nil comment.post.title
+      assert_not_nil post.author.name
     end
   end