DirtyModel uses a hash to keep track of any changes made to attributes

of an instance. When using the attribute_will_change! method, you must
supply a string and not a symbol or the *_changed? method will break
(because it is looking for the attribute name as a string in the keys
of the underlying hash). To remedy this, I simply made the underlying
hash a HashWithIndifferentAccess so it won't matter if you supply
the attribute name as a symbol or string to attribute_will_change!.

1 files changed, 1 insertions, 1 deletions

diff --git a/activemodel/lib/active_model/dirty.rb b/activemodel/lib/active_model/dirty.rb
index 6e67cd2285..b89b98feed 100644
--- a/activemodel/lib/active_model/dirty.rb
+++ b/activemodel/lib/active_model/dirty.rb
@@ -139,7 +139,7 @@ module ActiveModel
     #   person.name = 'robert'
     #   person.changed_attributes # => {"name" => "bob"}
     def changed_attributes
-      @changed_attributes ||= {}
+      @changed_attributes ||= ActiveSupport::HashWithIndifferentAccess.new
     end
 
     private