Adding old_password reader method to authenticatable

lib/devise/models/authenticatable.rb

@@ -47,7 +47,7 @@ module Devise
           extend ClassMethods
           extend SessionSerializer
 
-          attr_reader :password
+          attr_reader :password, :old_password
           attr_accessor :password_confirmation
         end
       end

test/models/authenticatable_test.rb

@@ -160,6 +160,10 @@ class AuthenticatableTest < ActiveSupport::TestCase
     end
   end
 
+  test 'should respond to old password' do
+    assert new_user.respond_to?(:old_password)
+  end
+
   test 'should update password with valid old password' do
     user = create_user
     assert user.update_with_password(:old_password => '123456',