Add a test for querying serialized attributes containing Module

Extracted from rails#47352

Author: byroot

activerecord/test/cases/serialized_attribute_test.rb

@@ -9,6 +9,12 @@
 class SerializedAttributeTest < ActiveRecord::TestCase
   def setup
     ActiveRecord.use_yaml_unsafe_load = true
+    @yaml_column_permitted_classes_default = ActiveRecord.yaml_column_permitted_classes
+  end
+
+  def teardown
+    Topic.serialize("content")
+    ActiveRecord.yaml_column_permitted_classes = @yaml_column_permitted_classes_default
   end
 
   fixtures :topics, :posts
@@ -23,8 +29,8 @@ class ImportantTopic < Topic
     serialize :important, type: Hash
   end
 
-  teardown do
-    Topic.serialize("content")
+  class ClassifiedTopic < Topic
+    serialize :important, type: Class
   end
 
   def test_serialize_does_not_eagerly_load_columns
@@ -166,6 +172,14 @@ def test_serialized_string_attribute
     assert_equal(myobj, topic.content)
   end
 
+  def test_serialized_class_attribute
+    ActiveRecord.yaml_column_permitted_classes += [Class]
+
+    topic = ClassifiedTopic.create(important: Symbol).reload
+    assert_equal(Symbol, topic.important)
+    assert_not_empty ClassifiedTopic.where(important: Symbol)
+  end
+
   def test_nil_serialized_attribute_without_class_constraint
     topic = Topic.new
     assert_nil topic.content
@@ -551,9 +565,17 @@ def test_serialized_attribute_works_under_concurrent_initial_access
 
 class SerializedAttributeTestWithYamlSafeLoad < SerializedAttributeTest
   def setup
+    @use_yaml_unsafe_load = ActiveRecord.use_yaml_unsafe_load
+    @yaml_column_permitted_classes_default = ActiveRecord.yaml_column_permitted_classes
     ActiveRecord.use_yaml_unsafe_load = false
   end
 
+  def teardown
+    Topic.serialize("content")
+    ActiveRecord.yaml_column_permitted_classes = @yaml_column_permitted_classes_default
+    ActiveRecord.use_yaml_unsafe_load = @use_yaml_unsafe_load
+  end
+
   def test_serialized_attribute
     Topic.serialize("content", type: String)