2 files changed, 20 insertions, 16 deletions

diff --git a/activerecord/lib/active_record/scoping/default.rb b/activerecord/lib/active_record/scoping/default.rb
index 2daa48859a..70b2693b28 100644
--- a/activerecord/lib/active_record/scoping/default.rb
+++ b/activerecord/lib/active_record/scoping/default.rb
@@ -5,11 +5,8 @@ module ActiveRecord
 
       included do
         # Stores the default scope for the class.
-        class_attribute :default_scopes, instance_writer: false, instance_predicate: false
-        class_attribute :default_scope_override, instance_writer: false, instance_predicate: false
-
-        self.default_scopes = []
-        self.default_scope_override = nil
+        class_attribute :default_scopes, instance_writer: false, instance_predicate: false, default: []
+        class_attribute :default_scope_override, instance_writer: false, instance_predicate: false, default: nil
       end
 
       module ClassMethods
@@ -110,7 +107,11 @@ module ActiveRecord
 
             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
diff --git a/activerecord/lib/active_record/scoping/named.rb b/activerecord/lib/active_record/scoping/named.rb
index 27cdf8cb7e..a61fdd6454 100644
--- a/activerecord/lib/active_record/scoping/named.rb
+++ b/activerecord/lib/active_record/scoping/named.rb
@@ -30,12 +30,15 @@ module ActiveRecord
         end
 
         def default_scoped # :nodoc:
-          scope = build_default_scope
+          scope = relation
+          build_default_scope(scope) || scope
+        end
 
-          if scope
-            relation.spawn.merge!(scope)
+        def default_extensions # :nodoc:
+          if scope = current_scope || build_default_scope
+            scope.extensions
           else
-            relation
+            []
           end
         end
 
@@ -156,17 +159,17 @@ module ActiveRecord
 
           if body.respond_to?(:to_proc)
             singleton_class.send(:define_method, name) do |*args|
-              scope = all.scoping { instance_exec(*args, &body) }
+              scope = all
+              scope = scope.scoping { instance_exec(*args, &body) || scope }
               scope = scope.extending(extension) if extension
-
-              scope || all
+              scope
             end
           else
             singleton_class.send(:define_method, name) do |*args|
-              scope = all.scoping { body.call(*args) }
+              scope = all
+              scope = scope.scoping { body.call(*args) || scope }
               scope = scope.extending(extension) if extension
-
-              scope || all
+              scope
             end
           end
         end