Ruby on rails 调试坎坎

我正在尝试调试下面的块

  can :create, Todo do |todo|
    todo.user.account == user.account
  end

我正在使用

todocontroller

顶部的

load\u和\u authorize\u资源

我遇到的问题是执行：create操作时，“account”是上述
todo.user.account
的nil方法。todo对象在传递时似乎没有完全实例化；我不知道如何控制这一点

以下是TodosController的相关部分：

  def new
    #@todo = Todo.new
    @todo = current_user.todos.build
    respond_to do |format|
      format.html # new.html.erb
      format.json { render :json => @todo }
    end
  end

  def create
    #@todo = Todo.new(params[:todo])

    #Build the @todo object including the relations of who's made this todo.
    @todo = current_user.todos.build(params[:todo])
    @todo.subscriptions.build(:user => current_user, :todo => @todo)
    @todo.subscriptions.build(:user => @todo.assignee, :todo => @todo)
    respond_to do |format|
      if @todo.save
        #format.html { redirect_to @todo, :notice => 'Todo was successfully created.' }
        Notifier.notify_assignee(@todo,current_user).deliver
        format.html { redirect_to :back }
        format.json { render :json => @todo, :status => :created, :location => @todo }
      else
        format.html { render :action => "new" }
        format.json { render :json => @todo.errors, :status => :unprocessable_entity }
      end
    end
  end

然后：

def create
  #@todo = Todo.new(params[:todo])

  #Build the @todo object including the relations of who's made this todo.
  @todo = current_user.todos.build(params[:todo])
  authorize! :create, @todo

然后：

def create
  #@todo = Todo.new(params[:todo])

  #Build the @todo object including the relations of who's made this todo.
  @todo = current_user.todos.build(params[:todo])
  authorize! :create, @todo