Pitfall: ResourceController overwrites where ActiveRecord enqueues

Defining one callback several times in the same class behaves different in ActiveRecord and ResourceController.
While in ActiveRecord the callbacks are enqueued, they overwrite each other in ResourceController.

ActiveRecord - a common practice

Copyclass Post < ActiveRecord::Base
  does 'post/behavior'
  before_validation :do_something
end

module Post::BehaviorTrait
  as_trait do
    before_validation :do_something_else
  end
end

do_something_else and do_something are executed before validation in exactly this order

ResourceController - here you have to be careful

Copyclass PostController
  include ResourceController::Controller
  does 'post_controller/behavior'
  index.before { do_something }
end

module PostController::BehaviorTrait
  as_trait do
    index.before { do_something_else }
  end
end

Only do_something is executed before index because the callback defined in the trait is overwritten.