AwesomeNestedSet + Rails 4.1.4`neested_set_options`拋出異常

Question

我有一個名為Collection的模型，配置如下：

acts_as_nested_set scope: :account, dependent: :destroy
belongs_to :parent, class_name: 'Collection'

使用nested_set_options視圖幫助程序工作正常，直到我升級到Rails 4.1.4（從4.0.5開始）：

<%= f.input :parent_id, label: 'Parent Collection',
            collection: nested_set_options(@collections) { |collection|
              "#{'-' * collection.level} #{collection.name}"
            },
            include_blank: '-- No Parent --' %>

我得到這個例外：

undefined method `name' for nil:NilClass

/Users/cpeters/Sites/plugins/awesome_nested_set/lib/awesome_nested_set/model.rb:45:in  `add_to_inverse_association'
/Users/cpeters/Sites/plugins/awesome_nested_set/lib/awesome_nested_set/model.rb:37:in `block in associate_parents'
activerecord (4.1.4) lib/active_record/relation/delegation.rb:46:in `each'
activerecord (4.1.4) lib/active_record/relation/delegation.rb:46:in `each'
/Users/cpeters/Sites/plugins/awesome_nested_set/lib/awesome_nested_set/model.rb:31:in `associate_parents'
/Users/cpeters/Sites/plugins/awesome_nested_set/lib/awesome_nested_set/helper.rb:33:in `block in nested_set_options'
/Users/cpeters/Sites/plugins/awesome_nested_set/lib/awesome_nested_set/helper.rb:32:in `each'
/Users/cpeters/Sites/plugins/awesome_nested_set/lib/awesome_nested_set/helper.rb:32:in `nested_set_options'
app/views/admin/resources/collections/_form.html.erb:7:in `block in _app_views_admin_resources_collections__form_html_erb__1427458998633439544_70350945783440'

這是從GitHub運行最新的（提交f823ffb ）。

Answer 1

事實證明，我的belongs_to配置不是必需的，並且導致了問題。

我從模型中刪除了這一行，我的所有測試都通過了，應用程序正常工作：

belongs_to :parent, class_name: 'Collection'

我不確定我之前是否因為某種原因而把它放在那里，但我覺得連一行代碼都是一個勝利。