Rails 4.1.4 ' nested_set_options '抛出异常

Question

我有一个名为Collection的模型，它被配置为:

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

使用nested_set_options视图助手工作得很好，直到我升级到Rails 4.1.4(从4.0.5):

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

我得到了这个异常:

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'

这是最新的GitHub(提交f823ffb)。

Answer 1

事实证明，我的belongs_to配置是不需要的，并且导致了问题。

我从模型中删除了这一行，并且我所有的测试都通过了，并且应用程序工作正常:

belongs_to :parent, class_name: 'Collection'

不确定我之前是不是有什么原因，但我觉得即使少了一行代码也是一种胜利