Only use the `_before_type_cast` in the form when from user input

While we don't want to change the form input when validations fail,
blindly using `_before_type_cast` will cause the input to display the
wrong data for any type which does additional work on database values.

1 files changed, 9 insertions, 2 deletions

diff --git a/actionview/lib/action_view/helpers/tags/base.rb b/actionview/lib/action_view/helpers/tags/base.rb
index f8abb19698..7740c60eac 100644
--- a/actionview/lib/action_view/helpers/tags/base.rb
+++ b/actionview/lib/action_view/helpers/tags/base.rb
@@ -32,12 +32,19 @@ module ActionView
           unless object.nil?
             method_before_type_cast = @method_name + "_before_type_cast"
 
-            object.respond_to?(method_before_type_cast) ?
-              object.send(method_before_type_cast) :
+            if value_came_from_user?(object) && object.respond_to?(method_before_type_cast)
+              object.public_send(method_before_type_cast)
+            else
               value(object)
+            end
           end
         end
 
+        def value_came_from_user?(object)
+          method_name = "#{@method_name}_came_from_user?"
+          !object.respond_to?(method_name) || object.public_send(method_name)
+        end
+
         def retrieve_object(object)
           if object
             object