Merge pull request #29293 from kamipo/fix_sti_with_default_scope

Fix `default_scoped` with defined `default_scope` on STI model

activerecord/lib/active_record/scoping/default.rb

@@ -110,7 +110,11 @@ def build_default_scope(base_rel = nil)
 
             if default_scope_override
               # The user has defined their own default scope method, so call that
-              evaluate_default_scope { default_scope }
+              evaluate_default_scope do
+                if scope = default_scope
+                  (base_rel ||= relation).merge(scope)
+                end
+              end
             elsif default_scopes.any?
               base_rel ||= relation
               evaluate_default_scope do

activerecord/test/cases/inheritance_test.rb

 require "cases/helper"
 require "models/author"
 require "models/company"
+require "models/membership"
 require "models/person"
 require "models/post"
 require "models/project"
@@ -29,7 +30,7 @@ def assign_store_full_sti_class(flag)
 
 class InheritanceTest < ActiveRecord::TestCase
   include InheritanceTestHelper
-  fixtures :companies, :projects, :subscribers, :accounts, :vegetables
+  fixtures :companies, :projects, :subscribers, :accounts, :vegetables, :memberships
 
   def test_class_with_store_full_sti_class_returns_full_name
     with_store_full_sti_class do
@@ -435,6 +436,10 @@ def test_scope_inherited_properly
     assert_nothing_raised { Company.of_first_firm }
     assert_nothing_raised { Client.of_first_firm }
   end
+
+  def test_inheritance_with_default_scope
+    assert_equal 1, SelectedMembership.count(:all)
+  end
 end
 
 class InheritanceComputeTypeTest < ActiveRecord::TestCase