開発中のアプリを Rails 4.2 から Rails 5 beta1.1 にアップグレードしています。アプリはアップグレード前にうまく機能しました。基本的なアップグレード手順 (Ruby の更新、Rails の更新、および関連する手順: http://edgeguides.rubyonrails.org/upgrading_ruby_on_rails.html ) を完了しました。Gemfile も最新の Gem に更新されています。
$ rails middleware または $ rails console または $ rails server を実行すると、次のエラーが表示されます。
No such middleware to insert after: ActionDispatch::ParamsParser
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/actionpack/lib/action_dispatch/middleware/stack.rb:108:in `assert_index'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/actionpack/lib/action_dispatch/middleware/stack.rb:80:in `insert_after'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/configuration.rb:69:in `block in merge_into'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/configuration.rb:68:in `each'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/configuration.rb:68:in `merge_into'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/engine.rb:507:in `block in app'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/engine.rb:504:in `synchronize'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/engine.rb:504:in `app'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/application/finisher.rb:34:in `block in <module:Finisher>'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/initializable.rb:30:in `instance_exec'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/initializable.rb:30:in `run'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/initializable.rb:55:in `block in run_initializers'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/initializable.rb:54:in `run_initializers'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/application.rb:350:in `initialize!'
.../config/environment.rb:5:in `<top (required)>'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/activesupport/lib/active_support/dependencies.rb:302:in `require'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/activesupport/lib/active_support/dependencies.rb:302:in `block in require'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/activesupport/lib/active_support/dependencies.rb:268:in `load_dependency'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/activesupport/lib/active_support/dependencies.rb:302:in `require'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/application.rb:326:in `require_environment!'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/application.rb:446:in `block in run_tasks_blocks'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/commands/rake_proxy.rb:13:in `block in run_rake_task'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/commands/rake_proxy.rb:10:in `run_rake_task'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/commands/commands_tasks.rb:51:in `run_command!'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/command.rb:20:in `run'
.../.rvm/gems/ruby-2.3.0/bundler/gems/rails-dbf67b3a6f54/railties/lib/rails/commands.rb:19:in `<top (required)>'
bin/rails:4:in `require'
bin/rails:4:in `<main>'
これは、ActionDispatch::ParamsParser が Rails 5 ベータ ミドルウェア ( https://github.com/rails/rails/commit/38d2bf5fd1f3e014f2397898d371c339baa627b1 ) から削除されたことに関連しています。しかし、どういうわけか、私のアプリはまだそれを探しているようです。
config/application.rb の ActionDispatch::ParamsParser を削除するなど色々試しましたが、ダメだったので追加してみました。同じエラー。このエラーを回避する方法はありますか?