1 files changed, 6 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 91bfa4d131..4533f3263f 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -655,6 +655,10 @@ module ActiveRecord
     #    # SELECT `posts`.* FROM `posts`  WHERE (('id = 1' OR 'author_id = 3'))
     #
     def or(other)
+      unless other.is_a? Relation
+        raise ArgumentError, "You have passed #{other.class.name} object to #or. Pass an ActiveRecord::Relation object instead."
+      end
+
       spawn.or!(other)
     end
 
@@ -1112,6 +1116,8 @@ module ActiveRecord
 
       order_query.flat_map do |o|
         case o
+        when Arel::Attribute
+          o.desc
         when Arel::Nodes::Ordering
           o.reverse
         when String