ruby-on-rails - RSpecでacts_as_nested_setするモデルのテスト

Question

私は、以下を使用するOrganizationモデルを持っています:acts_as_nested_setawesome_nested_set

class Organization < ActiveRecord::Base
  acts_as_nested_set
  attr_accessible :name, :location_id, :parent_id

  has_many :org_prod_relationships, dependent: :destroy
  has_many :products, through: :org_prod_relationships

  def has_product?(prod)
    org_prod_relationships.find_by_product_id(prod.id)
  end

  def add_product!(prod)
    org_prod_relationships.create!(product_id: prod.id)
  end

  def publish_product!(prod)
    self.descendants.each do |d|
      d.add_product!(prod)
    end
  end
end

RSpec forpublish_product!でテストを作成するにはどうすればよいですか?また、これはネストされたセットで作成するための間違ったアプローチorg_product_relationshipsであり、したがってテストするのは難しいですか? 私の非動作の試みはここにあります（より大きな仕様ファイルから切り取られました）https://gist.github.com/3911555。

編集: エラー メッセージを含めるように更新します。79行目と80行目は次のとおりです。

it { should have_product(product) }
its(:products) { should include(product) }

要旨で。

---

Failures:

  1) Organization publishes_product 
     Failure/Error: it { should have_product(product) }
       expected #has_product?(#<Product id: 34, name: "floo powder", created_at: "2012-10-21 14:15:08", updated_at: "2012-10-21 14:15:08", photo_file_name: nil, photo_content_type: nil, photo_file_size: nil, photo_updated_at: nil>) to return true, got false
     # ./spec/models/organization_spec.rb:79:in `block (3 levels) in <top (required)>'

  2) Organization publishes_product products 
     Failure/Error: its(:products) { should include(product) }
       expected [] to include #<Product id: 35, name: "floo powder", created_at: "2012-10-21 14:15:08", updated_at: "2012-10-21 14:15:08", photo_file_name: nil, photo_content_type: nil, photo_file_size: nil, photo_updated_at: nil>
       Diff:
       @@ -1,2 +1,2 @@
       -[#<Product id: 35, name: "floo powder", created_at: "2012-10-21 14:15:08", updated_at: "2012-10-21 14:15:08", photo_file_name: nil, photo_content_type: nil, photo_file_size: nil, photo_updated_at: nil>]
       +[]
     # ./spec/models/organization_spec.rb:80:in `block (3 levels) in <top (required)>'

Finished in 29.93 seconds
184 examples, 2 failures

Failed examples:

rspec ./spec/models/organization_spec.rb:79 # Organization publishes_product 
rspec ./spec/models/organization_spec.rb:80 # Organization publishes_product products