Test ignored_columns value is inheritable by subclasses

activerecord/test/cases/base_test.rb

@@ -1512,17 +1512,24 @@ def test_default_values_are_deeply_dupped
     cache_columns = Developer.connection.schema_cache.columns_hash(Developer.table_name)
     assert_includes cache_columns.keys, "first_name"
     assert_not_includes Developer.columns_hash.keys, "first_name"
+    assert_not_includes SubDeveloper.columns_hash.keys, "first_name"
   end
 
   test "ignored columns have no attribute methods" do
     refute Developer.new.respond_to?(:first_name)
     refute Developer.new.respond_to?(:first_name=)
     refute Developer.new.respond_to?(:first_name?)
+    refute SubDeveloper.new.respond_to?(:first_name)
+    refute SubDeveloper.new.respond_to?(:first_name=)
+    refute SubDeveloper.new.respond_to?(:first_name?)
   end
 
   test "ignored columns don't prevent explicit declaration of attribute methods" do
     assert Developer.new.respond_to?(:last_name)
     assert Developer.new.respond_to?(:last_name=)
     assert Developer.new.respond_to?(:last_name?)
+    assert SubDeveloper.new.respond_to?(:last_name)
+    assert SubDeveloper.new.respond_to?(:last_name=)
+    assert SubDeveloper.new.respond_to?(:last_name?)
   end
 end

activerecord/test/models/developer.rb

@@ -85,6 +85,9 @@ def track_instance_count
   private :track_instance_count
 end
 
+class SubDeveloper < Developer
+end
+
 class AuditLog < ActiveRecord::Base
   belongs_to :developer, validate: true
   belongs_to :unvalidated_developer, class_name: "Developer"