<備忘録> railsサーバー立ち上げ時エラー対応

環境

• macOS Monterey 12.0.1
• Ruby 2.6.3
• Bundler 2.2.17
• Rails 6.0.4.7

エラー内容

ubuntu:~/environment/hello_app (master) $ rails s
=> Booting Puma
=> Rails 6.0.4 application starting in development
=> Run `rails server --help` for more startup options
warning ../../package.json: No license field
Puma starting in single mode...
* Version 4.3.6 (ruby 2.6.3-p62), codename: Mysterious Traveller
* Min threads: 5, max threads: 5
* Environment: development
* Listening on tcp://127.0.0.1:8080
* Listening on tcp://[::1]:8080
Use Ctrl-C to stop

どうやらyarnのインストールを複数回行ったことが原因らしい。

rm -rf yarn.lock

参考文献