2 files changed, 31 insertions, 3 deletions
diff --git a/activerecord/test/cases/scoping/default_scoping_test.rb b/activerecord/test/cases/scoping/default_scoping_test.rb
index 86316ab476..ad5ca70f36 100644
--- a/activerecord/test/cases/scoping/default_scoping_test.rb
+++ b/activerecord/test/cases/scoping/default_scoping_test.rb
@@ -459,4 +459,18 @@ class DefaultScopingTest < ActiveRecord::TestCase
     scope = Bus.all
     assert_equal scope.where_clause.ast.children.length, 1
   end
+
+  def test_sti_conditions_are_not_carried_in_default_scope
+    ConditionalStiPost.create! body: ''
+    SubConditionalStiPost.create! body: ''
+    SubConditionalStiPost.create! title: 'Hello world', body: ''
+
+    assert_equal 2, ConditionalStiPost.count
+    assert_equal 2, ConditionalStiPost.all.to_a.size
+    assert_equal 3, ConditionalStiPost.unscope(where: :title).to_a.size
+
+    assert_equal 1, SubConditionalStiPost.count
+    assert_equal 1, SubConditionalStiPost.all.to_a.size
+    assert_equal 2, SubConditionalStiPost.unscope(where: :title).to_a.size
+  end
 end
diff --git a/activerecord/test/cases/scoping/relation_scoping_test.rb b/activerecord/test/cases/scoping/relation_scoping_test.rb
index 4bfffbe9c6..c15d57460b 100644
--- a/activerecord/test/cases/scoping/relation_scoping_test.rb
+++ b/activerecord/test/cases/scoping/relation_scoping_test.rb
@@ -209,9 +209,23 @@ class RelationScopingTest < ActiveRecord::TestCase
     assert_not_equal [], Developer.all
   end
 
-  def test_current_scope_does_not_pollute_other_subclasses
-    Post.none.scoping do
-      assert StiPost.all.any?
+  def test_current_scope_does_not_pollute_sibling_subclasses
+    Comment.none.scoping do
+      assert_not SpecialComment.all.any?
+      assert_not VerySpecialComment.all.any?
+      assert_not SubSpecialComment.all.any?
+    end
+
+    SpecialComment.none.scoping do
+      assert Comment.all.any?
+      assert VerySpecialComment.all.any?
+      assert_not SubSpecialComment.all.any?
+    end
+
+    SubSpecialComment.none.scoping do
+      assert Comment.all.any?
+      assert VerySpecialComment.all.any?
+      assert SpecialComment.all.any?
     end
   end
 end