modulize AR::NullRelation

now we can invoke previously added scope extension methods

3 files changed, 9 insertions, 4 deletions

diff --git a/activerecord/lib/active_record/null_relation.rb b/activerecord/lib/active_record/null_relation.rb
index c2d3eeb8ce..ff79f1d398 100644
--- a/activerecord/lib/active_record/null_relation.rb
+++ b/activerecord/lib/active_record/null_relation.rb
@@ -2,7 +2,7 @@
 
 module ActiveRecord
   # = Active Record Null Relation
-  class NullRelation < Relation
+  module NullRelation
     def exec_queries
       @records = []
     end
@@ -60,4 +60,4 @@ module ActiveRecord
     end
 
   end
-end
\ No newline at end of file
+end
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 19fe8155d9..a89d0f3ebf 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -279,7 +279,7 @@ module ActiveRecord
     #   end
     #
     def none
-      NullRelation.new(@klass, @table)
+      scoped.extending(NullRelation)
     end
 
     def readonly(value = true)
diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index 2dc8f0053b..90367df5ee 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -226,7 +226,6 @@ class RelationTest < ActiveRecord::TestCase
     assert_no_queries do
       assert_equal [], Developer.none
       assert_equal [], Developer.scoped.none
-      assert           Developer.none.is_a?(ActiveRecord::NullRelation)
     end
   end
 
@@ -236,6 +235,12 @@ class RelationTest < ActiveRecord::TestCase
     end
   end
 
+  def test_none_chainable_to_existing_scope_extension_method
+    assert_no_queries do
+      assert_equal 1, Topic.anonymous_extension.none.one
+    end
+  end
+
   def test_none_chained_to_methods_firing_queries_straight_to_db
     assert_no_queries do
       assert_equal [],    Developer.none.pluck(:id) # => uses select_all