1 files changed, 12 insertions, 7 deletions
diff --git a/activerecord/test/cases/serialized_attribute_test.rb b/activerecord/test/cases/serialized_attribute_test.rb
index 1192b30b14..ecf81b2042 100644
--- a/activerecord/test/cases/serialized_attribute_test.rb
+++ b/activerecord/test/cases/serialized_attribute_test.rb
@@ -1,18 +1,23 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "models/topic"
-require "models/reply"
 require "models/person"
 require "models/traffic_light"
 require "models/post"
-require "bcrypt"
 
 class SerializedAttributeTest < ActiveRecord::TestCase
   fixtures :topics, :posts
 
   MyObject = Struct.new :attribute1, :attribute2
 
+  class Topic < ActiveRecord::Base
+    serialize :content
+  end
+
+  class ImportantTopic < Topic
+    serialize :important, Hash
+  end
+
   teardown do
     Topic.serialize("content")
   end
@@ -49,10 +54,10 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   def test_serialized_attributes_from_database_on_subclass
     Topic.serialize :content, Hash
 
-    t = Reply.new(content: { foo: :bar })
+    t = ImportantTopic.new(content: { foo: :bar })
     assert_equal({ foo: :bar }, t.content)
     t.save!
-    t = Reply.last
+    t = ImportantTopic.last
     assert_equal({ foo: :bar }, t.content)
   end
 
@@ -367,9 +372,9 @@ class SerializedAttributeTest < ActiveRecord::TestCase
   end
 
   def test_serialized_attribute_works_under_concurrent_initial_access
-    model = Topic.dup
+    model = Class.new(Topic)
 
-    topic = model.last
+    topic = model.create!
     topic.update group: "1"
 
     model.serialize :group, JSON