4 files changed, 26 insertions, 2 deletions
diff --git a/activerecord/test/cases/associations/extension_test.rb b/activerecord/test/cases/associations/extension_test.rb
index 87d842f21d..f707a170f5 100644
--- a/activerecord/test/cases/associations/extension_test.rb
+++ b/activerecord/test/cases/associations/extension_test.rb
@@ -78,6 +78,12 @@ class AssociationsExtensionsTest < ActiveRecord::TestCase
     assert_equal post.association(:comments), post.comments.where("1=1").the_association
   end
 
+  def test_association_with_default_scope
+    assert_raises OopsError do
+      posts(:welcome).comments.destroy_all
+    end
+  end
+
   private
 
     def extend!(model)
diff --git a/activerecord/test/cases/associations/has_many_associations_test.rb b/activerecord/test/cases/associations/has_many_associations_test.rb
index 6a479a344c..a794eba691 100644
--- a/activerecord/test/cases/associations/has_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_associations_test.rb
@@ -2251,7 +2251,15 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
   test "association with extend option with multiple extensions" do
     post = posts(:welcome)
     assert_equal "lifo",  post.comments_with_extend_2.author
-    assert_equal "hello", post.comments_with_extend_2.greeting
+    assert_equal "hullo", post.comments_with_extend_2.greeting
+  end
+
+  test "extend option affects per association" do
+    post = posts(:welcome)
+    assert_equal "lifo",  post.comments_with_extend.author
+    assert_equal "lifo",  post.comments_with_extend_2.author
+    assert_equal "hello", post.comments_with_extend.greeting
+    assert_equal "hullo", post.comments_with_extend_2.greeting
   end
 
   test "delete record with complex joins" do
diff --git a/activerecord/test/models/comment.rb b/activerecord/test/models/comment.rb
index 76b484e616..8cba788598 100644
--- a/activerecord/test/models/comment.rb
+++ b/activerecord/test/models/comment.rb
@@ -19,6 +19,16 @@ class Comment < ActiveRecord::Base
   has_many :children, class_name: "Comment", foreign_key: :parent_id
   belongs_to :parent, class_name: "Comment", counter_cache: :children_count
 
+  class ::OopsError < RuntimeError; end
+
+  module OopsExtension
+    def destroy_all(*)
+      raise OopsError
+    end
+  end
+
+  default_scope { extending OopsExtension }
+
   # Should not be called if extending modules that having the method exists on an association.
   def self.greeting
     raise
diff --git a/activerecord/test/models/post.rb b/activerecord/test/models/post.rb
index a2028b3eb9..4c913b3b72 100644
--- a/activerecord/test/models/post.rb
+++ b/activerecord/test/models/post.rb
@@ -13,7 +13,7 @@ class Post < ActiveRecord::Base
 
   module NamedExtension2
     def greeting
-      "hello"
+      "hullo"
     end
   end