has_many through association sql error

Question

So, I'm trying to test my models associations with the following test:

it 'retrieve items registered under person' do
  p = FactoryGirl.create(:person)
  o = FactoryGirl.create(:order, customer: p)
  o.customer.should == p
  i = FactoryGirl.create(:item)
  o.items << i
  o.save
  p.items.count.should == 1
end

My models:

class Person < AR:Base
  has_many :orders, :as => :customer
  has_many :items, :through => :orders
end

class Order < AR:Base
  has_many :items
  belongs_to :customer, :class_name => Person
end

class Item < AR:Base
  belongs_to :order
  has_one :customer, :class_name => Person, :through => :order
end

But when I run the test it gives me the following error:

SQLite3::SQLException: no such column: orders.customer_type: SELECT COUNT(*) FROM "items" INNER JOIN "orders" ON "items"."order_id" = "orders"."id" WHERE "orders"."customer_id" = 1 AND "orders"."customer_type" = 'Person'

What am I doing wrong?

Update: The problem was on the ':as => :customer' bit. But my real problem was with the test. I should have assigned an order in the creation of an item.

Answer 1

It's because the :as option specifies a polymorphic interface. This explains "orders"."customer_type" = 'Person' in the where clause. I think what you mean to do is:

class Person < ActiveRecord::Base
  has_many :orders, :foreign_key => :customer_id
  has_many :items, :through => :orders
end

See the :as option in the guide.