class ActiveRecord::Associations::BelongsToPolymorphicAssociation

def inverse_reflection_for(record)
  reflection.polymorphic_inverse_of(record.class)
end

def klass
  type = owner[reflection.foreign_type]
  type.presence && owner.class.polymorphic_class_for(type)
end

def raise_on_type_mismatch!(record)
  # A polymorphic association cannot have a type mismatch, by definition
end

def replace_keys(record, force: false)
  super
  target_type = record ? record.class.polymorphic_name : nil
  if force || owner._read_attribute(reflection.foreign_type) != target_type
    owner[reflection.foreign_type] = target_type
  end
end

def saved_change_to_target?
  super || owner.saved_change_to_attribute?(reflection.foreign_type)
end

def stale_state
  foreign_key = super
  foreign_key && [foreign_key.to_s, owner[reflection.foreign_type].to_s]
end

def target_changed?
  super || owner.attribute_changed?(reflection.foreign_type)
end

def target_previously_changed?
  super || owner.attribute_previously_changed?(reflection.foreign_type)
end