Assign_attributes only assigns child attr_accessor values if a table column is changed on updates

Here's the set up

class Order
  has_many :items
  accepts_nested_attributes_for :items
end

class Item
  belongs_to :order
  attr_accessor :discount # this is NOT a table column, just a virtual attribute I want to be able to assign
end

Let's say I have an existing order @order. I noticed that if I were to try to assign discount on the child Item from the Order model, this only works if some other attribute on the child Item is changed.

@order.assign_attributes({"items_attributes"=>[{"id"=>40, "discount"=>"test"}]})
@order.items.first.discount
=> nil

@order.assign_attributes({"items_attributes"=>[{"id"=>40, "discount"=>"test", "admin_notes"=>"hello"}]})
# where admin_notes is a table column for Item
@order.items.first.discount
=> "test
@order.items.first.admin_notes
=> "hello"

Is there a quick setting change or something to change this? I'd like attr_accessor attributes to always be assigned even if no attributes are changing?

Solution

FWIW if anyone stumbles upon this.... it appears to have resolved itself. Was working on something else today and noticed that I can't duplicate the original error anymore. A lot has changed in code, not going to go back and dig into this to figure out what happened. I do know that key configuration variables that could have affected this have not changed, e.g., inverse_of flag set on both models, Order model set to accepts_nested_attributes_for :items