uninitialized constant XXXXXX::Rails::Application (NameError)の対処法

# 問題
新しくcoffeeに関するアプリを作ろうと、

```ruby:
rails new coffee
```

を実行、その後Gemfileにrspec-railsを追加し

```ruby:
bin/rails g rspec:install
```

を実行したところ

```ruby:
WARNING: Nokogiri was built against LibXML version 2.9.8, but has dynamically loaded 2.9.4
Traceback (most recent call last):
	24: from bin/rails:4:in `<main>'
	23: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
	22: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
	21: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/loaded_features_index.rb:83:in `register'
	20: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_bootsnap_lfi'
	19: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
	18: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/commands.rb:18:in `<main>'
	17: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/command.rb:46:in `invoke'
	16: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/command/base.rb:65:in `perform'
	15: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/thor-0.20.3/lib/thor.rb:387:in `dispatch'
	14: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/thor-0.20.3/lib/thor/invocation.rb:126:in `invoke_command'
	13: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/thor-0.20.3/lib/thor/command.rb:27:in `run'
	12: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/commands/generate/generate_command.rb:21:in `perform'
	11: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/railties-5.2.2.1/lib/rails/command/actions.rb:17:in `require_application_and_environment!'
	10: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:29:in `require'
	 9: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:20:in `require_with_bootsnap_lfi'
	 8: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/loaded_features_index.rb:83:in `register'
	 7: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `block in require_with_bootsnap_lfi'
	 6: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:21:in `require'
	 5: from /Users/reiforu/dev/coffee/config/application.rb:9:in `<main>'
	 4: from /Users/reiforu/dev/coffee/config/application.rb:10:in `<module:Coffee>'
	 3: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/active_support.rb:58:in `load_missing_constant'
	 2: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/active_support.rb:76:in `rescue in load_missing_constant'
	 1: from /Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/lib/bootsnap/load_path_cache/core_ext/active_support.rb:8:in `without_bootsnap_cache'

/Users/reiforu/dev/coffee/vendor/bundle/ruby/2.5.0/gems/bootsnap-1.4.1/
lib/bootsnap/load_path_cache/core_ext/active_support.rb:76:in `block in load_missing_constant': 

uninitialized constant Coffee::Rails::Application (NameError)

```

が発生。

zshを入れたばかりでrbenvが悪いのかとか、
readlineのリンクが張られてないのかとか
いろいろ試したんですが解決に至らず。

# 結局

問題は、<b>アプリ名をcoffeeとしていたこと</b>でした。

`rails new coffee_app`とし、同じくbundle install等したところ、うまくいきました。

<br>

おわり