Ruby on rails 添加迁移时出错：`default_controller_和_action'；：缺少：操作（ArgumentError）

我正在尝试添加以下迁移：

rails g migration AddConfirmableToUsers confirmation_token:string confirmed_at:datetime confirmation_sent_at:datetime unconfirmed_email:string

但是，它引发了以下错误，我无法进行故障排除：

/Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:179:in `default_controller_and_action': missing :action (ArgumentError)
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:72:in `normalize_options!'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:60:in `initialize'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:1308:in `new'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:1308:in `add_route'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:1287:in `decomposed_match'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:1269:in `block in match'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:1269:in `each'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:1269:in `match'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:254:in `root'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/mapper.rb:1321:in `root'
    from /Users/tn/rails_projects/rails-prelaunch-signup/config/routes.rb:5:in `block in <top (required)>'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/route_set.rb:289:in `instance_exec'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/route_set.rb:289:in `eval_block'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/actionpack-3.2.13/lib/action_dispatch/routing/route_set.rb:267:in `draw'
    from /Users/tn/rails_projects/rails-prelaunch-signup/config/routes.rb:1:in `<top (required)>'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:245:in `load'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:245:in `block in load'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:236:in `load_dependency'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:245:in `load'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application/routes_reloader.rb:40:in `block in load_paths'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application/routes_reloader.rb:40:in `each'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application/routes_reloader.rb:40:in `load_paths'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application/routes_reloader.rb:16:in `reload!'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application/routes_reloader.rb:26:in `block in updater'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/file_update_checker.rb:78:in `call'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/file_update_checker.rb:78:in `execute'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application/routes_reloader.rb:27:in `updater'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application/routes_reloader.rb:7:in `execute_if_updated'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application/finisher.rb:66:in `block in <module:Finisher>'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/initializable.rb:30:in `instance_exec'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/initializable.rb:30:in `run'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/initializable.rb:55:in `block in run_initializers'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/initializable.rb:54:in `each'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/initializable.rb:54:in `run_initializers'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application.rb:136:in `initialize!'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/railtie/configurable.rb:30:in `method_missing'
    from /Users/tn/rails_projects/rails-prelaunch-signup/config/environment.rb:5:in `<top (required)>'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `require'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `block in require'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:236:in `load_dependency'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `require'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/application.rb:103:in `require_environment!'
    from /Users/tn/.rvm/gems/ruby-2.0.0-rc1@global/gems/railties-3.2.13/lib/rails/commands.rb:25:in `<top (required)>'
    from script/rails:6:in `require'
    from script/rails:6:in `<main>'

User.rb

class User < ActiveRecord::Base
  rolify
  # Include default devise modules. Others available are:
  # :token_authenticatable, :encryptable, :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable, :confirmable,
         :recoverable, :rememberable, :trackable, :validatable

  # Setup accessible (or protected) attributes for your model
  attr_accessible :name, :email, :password, :password_confirmation, :remember_me

end

class用户

---

任何帮助都将不胜感激

它确实是您的路由文件：

root to: "root_path"

这应该是这样的：

root to: "controller#action"

---

root\u path

是当您的routes文件中有

root

定义时，Rails自动生成的助手名称。

谢谢@Ryan Bigg！我更新了routes文件，以反映教程Github页面上的实现：

root to: "controller#action"