validations.patch

diff --git a/activemodel/lib/active_model/validations.rb b/activemodel/lib/active_model/validations.rb
index a0f9045..efd071f 100644
--- a/activemodel/lib/active_model/validations.rb
+++ b/activemodel/lib/active_model/validations.rb
@@ -147,9 +147,9 @@ module ActiveModel
 
       # List all validators that being used to validate a specific attribute.
       def validators_on(*attributes)
-        attributes.inject([]) do |all, attribute|
-          all |= _validators[attribute.to_sym] || []
-        end
+        attributes.map do |attribute|
+          _validators[attribute.to_sym]
+        end.flatten
       end
 
       # Check if method is an attribute method or not.