Run backported serialized test without Identity Map

It fails with Identity Map because the find call returns the same
object, so the "content" attribute that we expect to raise "missing
attribute" is actually present.

1 files changed, 4 insertions, 2 deletions

diff --git a/activerecord/test/cases/base_test.rb b/activerecord/test/cases/base_test.rb
index efcfe3f612..5631ac9ce2 100644
--- a/activerecord/test/cases/base_test.rb
+++ b/activerecord/test/cases/base_test.rb
@@ -1449,8 +1449,10 @@ class BasicsTest < ActiveRecord::TestCase
     myobj = MyObject.new('value1', 'value2')
     topic = Topic.create(:content => myobj)
 
-    assert_equal(myobj, Topic.select(:content).find(topic.id).content)
-    assert_raise(ActiveModel::MissingAttributeError) { Topic.select(:id).find(topic.id).content }
+    ActiveRecord::IdentityMap.without do
+      assert_equal(myobj, Topic.select(:content).find(topic.id).content)
+      assert_raise(ActiveModel::MissingAttributeError) { Topic.select(:id).find(topic.id).content }
+    end
   ensure
     ActiveRecord::Base.time_zone_aware_attributes = false
   end