从Rails 2迁移到Rails 3的问题(没有,有吗?)

我已经将我的应用程序从Rails 2.3.8升级到Rails 3。

在完成了所有的基本工作(配置、路由和新的AR API,用Devise替换Authlogic)并使一些基本上是静态的页面显示良好之后,我在我的站点的其余部分得到了一个错误:

You have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occurred while evaluating nil.any?

当我引用时总是出现此错误 SomeModel 这是第一次。 E、 g.,在我的 news#index :

@news_story = NewsStory.new # gets called from before_filter

app/models/news_story.rb 无法加载。

我一整天都在和这个做斗争。有人知道发生了什么事吗?

# stack trace:
activesupport (3.0.0) lib/active_support/dependencies.rb:497:in `load_missing_constant'
activesupport (3.0.0) lib/active_support/dependencies.rb:183:in `block in const_missing'
activesupport (3.0.0) lib/active_support/dependencies.rb:181:in `each'
activesupport (3.0.0) lib/active_support/dependencies.rb:181:in `const_missing'
app/controllers/news_controller.rb:82:in `new_post'
activesupport (3.0.0) lib/active_support/callbacks.rb:451:in `_run__810448074__process_action__85542351__callbacks'
activesupport (3.0.0) lib/active_support/callbacks.rb:409:in `_run_process_action_callbacks'
activesupport (3.0.0) lib/active_support/callbacks.rb:93:in `run_callbacks'
actionpack (3.0.0) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (3.0.0) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
...

控制器动作:

class NewsController < ApplicationController
  before_filter :new_post_from_params, :only => :create
  before_filter :new_post, :only => [:index, :new]
  before_filter :find_post, :except => [:index, :create, :new]
  filter_access_to :all, :attribute_check => true

  def index
    @user = current_user
    @news = NewsStory.all
    respond_to do |format|
      format.html # index.html.erb
      format.xml { render :xml => @user.news }
    end
  end
  #...
  private

  def new_post_from_params
    @news_story = NewsStory.new(params[:news_story])
  end

  def new_post
    @news_story = NewsStory.new
  end

  def find_post
    @news_story = NewsStory.find(params[:id])
  end
end

其他信息:

• app/models/news_story.rb
• Gemfile

• config/application.rb

• Ruby版本:

  ~ $ ruby -v
  ruby 1.9.2p0 (2010-08-18 revision 29036) [i686-linux]
  

• irb(main):001:0> NewsStory.new
  => #<NewsStory id: nil, title: nil, body: nil, user_id: nil, created_at: nil, updated_at: nil>