ruby-on-rails - ID=# のユーザーが見つかりませんでした

Question

「編集」をクリックすると、次のエラーが表示されます。

Couldn't find User with id=#<ActiveRecord::Relation::ActiveRecord_Relation_User:0x2eb9b58> 

ActiveRecord::RecordNotFound in UsersController#edit

は次のUsersControllerとおりです。

class UsersController < ApplicationController
  before_action :set_user, only: [:index, :show, :edit, :create, :update, :destroy]
  ...
  def edit
    @user = User.find(params[:id])  #the error points to this line.
  end
  ...
end

フルトレースは次のとおりです。

Activerecord (4.0.0) lib/active_record/relation/finder_methods.rb:198: raise_record_not_found_exception!' activerecord (4.0.0) lib/active_record/relation/finder_methods.rb:284:infind_one で Activerecord (4.0.0) lib/active_record/relation/finder_methods.rb:268: find_with_ids' activerecord (4.0.0) lib/active_record/relation/finder_methods.rb:35:infind で activerecord-deprecated_finders (1.0.3) lib/active_record/deprecated_finders/relation.rb:122:in find' C:in find' app/controllers/users_controller.rb:18:in edit' actionpack (4.0.0) lib/action_controller/metal/implicit_render.rb:4:in send_action' actionpack (4.0.0) lib/abstract_controller/base.rb:189:in process_action' actionpack (4.0.0) lib/action_controller/metal/rendering.rb:10:in process_action' actionpack (4.0) .0) lib/abstract_controller/callbacks.rb:18: in block in process_action' activesupport (4.0.0) lib/active_support/callbacks.rb:413:in run _759441773__process_action__callbacks' activesupport (4.0.0) lib/active_support/callbacks.rb:80: in run_callbacks' actionpack (4.0.0) lib/abstract_controller/callbacks.rb:17:inprocess_action' actionpack (4.0.0) lib/action_controller/metal/rescue. rb:29:で process_action' actionpack (4.0.0) lib/action_controller/metal/instrumentation.rb:31:inblock in process_action' activesupport (4.0.0) lib/active_support/notifications.rb:159:in block in instrument' activesupport (4.0.0) lib/active_support/notifications/instrumenter.rb:20:ininstrument' activesupport (4.0.0) lib/active_support/notifications.rb:159:in instrument' actionpack (4.0.0) lib/action_controller/metal/instrumentation.rb:30:inprocess_action' actionpack (4.0.0) lib/ action_controller/metal/params_wrapper.rb:245:in process_action' activerecord (4.0.0) lib/active_record/railties/controller_runtime.rb:18:in process_action' actionpack (4.0.0) lib/abstract_controller/base.rb:136:in process' actionpack (4.0.0) lib/abstract_controller/rendering.rb:44:inprocess' actionpack (4.0.0) lib/action_controller/metal.rb:195:in dispatch' actionpack (4.0.0) lib/action_controller/metal/rack_delegation.rb:13:in dispatch ' actionpack (4.0.0) lib/action_controller/metal.rb:231: block in action' actionpack (4.0.0) lib/action_dispatch/routing/route_set.rb:80:in呼び出し中' actionpack (4.0.0) lib/action_dispatch/routing/route_set.rb:80:dispatch' actionpack (4.0.0) lib/action_dispatch/routing/route_set.rb:48:in 呼び出し中' actionpack (4.0.0) lib/action_dispatch /journey/router.rb:71:in block in call' actionpack (4.0.0) lib/action_dispatch/journey/router.rb:59:ineach' アクションパック (4.0.0) lib/action_dispatch/journey/router.rb:59:incall' actionpack (4.0.0) lib/action_dispatch/routing/route_set.rb:655:incall' ラック (1.5.2) lib/rack/etag.rb:23:in call' rack (1.5.2) lib/rack/conditionalget.rb:25:incall' ラック (1.5.2) lib/rack/head.rb:11:in call' actionpack (4.0.0) lib/action_dispatch/middleware/params_parser.rb:27:incall' actionpack (4.0.0) lib/action_dispatch/ middleware/flash.rb:241: in call' rack (1.5.2) lib/rack/session/abstract/id.rb:225:incontext' ラック (1.5.2) lib/rack/session/abstract/id.rb:220: in call' actionpack (4.0.0) lib/action_dispatch/middleware/cookies.rb:486:incall' activerecord (4.0.0) lib/active_record/query_cache.rb:36: in call' activerecord (4.0.0) lib/active_record/connection_adapters/abstract/connection_pool.rb:626:in call' activerecord (4.0.0) lib/active_record/migration.rb:369: call' actionpack (4.0.0) lib/action_dispatch/middleware/callbacks.rb:29:inin call' activesupport (4.0.0) lib/active_support/callbacks.rb:373: in _run__847569706__call__callbacks' activesupport (4.0.0) lib/active_support/callbacks.rb:80:inrun_callbacks' actionpack (4.0.0) lib /action_dispatch/middleware/callbacks.rb:27:in call' actionpack (4.0.0) lib/action_dispatch/middleware/reloader.rb:64:in call' actionpack (4.0.0) lib/action_dispatch/middleware/remote_ip.rb:76:in call' actionpack (4.0.0) lib/action_dispatch/middleware/debug_exceptions.rb:17:in call' actionpack (4.0.0) lib/action_dispatch/middleware/show_exceptions.rb :30:インチcall' railties (4.0.0) lib/rails/rack/logger.rb:38:incall_app' railties (4.0.0) lib/rails/rack/logger.rb:21:block in call' activesupport (4.0.0) lib/active_support/tagged_logging.rb:67:inタグ付きのブロック内 ' activesupport (4.0.0) lib/active_support/tagged_logging.rb:25: tagged' activesupport (4.0.0) lib/active_support/tagged_logging.rb:67:inタグ付きの railties (4.0.0) lib/rails/rack/logger.rb:21:in call' actionpack (4.0.0) lib/action_dispatch/middleware/request_id.rb:21:incall' ラック (1.5.2) lib/rack/methodoverride.rb:21:in call' rack (1.5.2) lib/rack/runtime.rb:17:incall' activesupport (4.0.0) lib/active_support/cache/strategy/local_cache. rb:83:in call' rack (1.5.2) lib/rack/lock.rb:17:incall' actionpack (4.0.0) lib/action_dispatch/middleware/static.rb:64:in call' railties (4.0.0) lib/rails/engine.rb:511:incall' railties (4.0.0) lib/rails/application.rb:97:in call' rack (1.5.2) lib/rack/lock.rb:17:incall' rack (1.5 .2) lib/rack/content_length.rb:14:in call' rack (1.5.2) lib/rack/handler/webrick.rb:60:inservice' C:/RailsInstaller/Ruby1.9.3/lib/ruby/1.9.1/webrick/httpserver.rb:138:in service' C:/RailsInstaller/Ruby1.9.3/lib/ruby/1.9.1/webrick/httpserver.rb:94:in run' C:/RailsInstaller/Ruby1 .9.3/lib/ruby/1.9.1/webrick/server.rb:191:「start_thread のブロック」で