ruby-on-rails – 为什么我的根节点最后将自己作为带有acts_as_t

新的root以一个parent_id结束,该parent_id匹配它的新id而不是NULL.成功更改现有根以将新根作为父级.

# Rake task
desc "Change categories to use new root"
task :make_new_category_root => :environment do
  Company.all.each do |company|
    current_roots = company.root_categories
    new_root = Category.new(name: "New root")
    new_root.company = company
    new_root.parent = nil
    if new_root.save
      current_roots.each do |current|
        current.parent = new_root
        current.save
      end
    end
  end

# Category class,abbreviated
class Category < ActiveRecord::Base
  include ActsAsTree
  acts_as_tree :order => "name"

  belongs_to :company,touch: true
  validates :name,uniqueness: { scope: :company_id },:if => :root?      
  scope :roots,where(:parent_id => nil)      
end