Polymorphic Association不使用ActiveHash

我有一个ActiveHash类，我想在多态关联中使用它：

class Person < ActiveRecord::Base
extend ActiveHash::Associations::ActiveRecordExtensions

belongs_to :placeable, polymorphic: true
end

class Country < ActiveHash::Base
include ActiveHash::Associations

has_many :people, as: :placeable

self.data = [

{ id: 1, name: 'US' },
{ id: 2, name: 'Canada' }

]
end

设置多态关联时，它会持久保存到将多态类型设置为的数据库ActiveHash::Base。稍后访问时，我收到undefined method 'arel_table'错误。

person = Person.create
person.placeable = Country.last
person.save
person
=> #

person.placeable
NoMethodError: undefined method `arel_table' for ActiveHash::Base:Class

from (irb):2

我也尝试将多态类型设置为Country，但我收到Country类的相同错误。

非多态belongs_to似乎工作得很好。