rubyのgemのコードリーディングをする時によく利用したことを 備忘録としてメモ。
（随時更新する。）
※rubyのバージョンは3.1.0
gemのファイルの場所を知りたい時
$LOAD_PATH.grep(/serach_word/)で検索できる。
例）devise関連のgemの場所を知りたい場合
rails c
irb(main):010:0> $LOAD_PATH.grep(/devise/)
=>
["YOUR_PATH/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/devise-4.8.1/lib",
"YOUR_PATH/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/devise-4.8.1/app/controllers",
"YOUR_PATH/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/devise-4.8.1/app/helpers",
"YOUR_PATH/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/devise-4.8.1/app/mailers"]
デバッグ
参考
ブレイクポイント
コード内にbinding.breakを書けば止まる
例
generators/devise/install_generator.rb
[12, 21] in ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/devise-4.8.1/lib/generators/devise/install_generator.rb
12|
13| desc "Creates a Devise initializer and copy locale files to your application."
14| class_option :orm, required: true
15|
16| def copy_initializer
=> 17| binding.break
18| unless options[:orm]
19| raise MissingORMError, <<-ERROR.strip_heredoc
20| An ORM must be set to install Devise in your application.
21|
=>#0 Devise::Generators::InstallGenerator#copy_initializer at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/devise-4.8.1/lib/generators/devise/install_generator.rb:17
#1 Thor::Command#run(instance=#<Devise::Generators::InstallGenerator:0..., args=[]) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/command.rb:27
# and 21 frames (use `bt' command for all frames)
(rdbg)
参考
バックトレース(backtrace)
ブレイクポイントで止まった状態でbacktraceを入力する
出力例
generators/devise/install_generator.rb
(rdbg) backtrace
=>#0 Devise::Generators::InstallGenerator#copy_initializer at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/devise-4.8.1/lib/generators/devise/install_generator.rb:17
#1 Thor::Command#run(instance=#<Devise::Generators::InstallGenerator:0..., args=[]) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/command.rb:27
#2 Thor::Invocation#invoke_command(command=#<struct Thor::Command name="copy_initia..., args=[]) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/invocation.rb:127
#3 block {|_="copy_initializer", command=#<struct Thor::Command name="copy_initia...|} in invoke_all at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/invocation.rb:134
#4 [C] Hash#each at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/invocation.rb:134
#5 [C] Enumerable#map at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/invocation.rb:134
#6 Thor::Invocation#invoke_all at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/invocation.rb:134
#7 #<Class:Thor::Group>#dispatch(command=nil, given_args=[], given_opts=nil, config={:behavior=>:invoke, :destination_root=>...) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/group.rb:232
#8 Thor::Base::ClassMethods#start(given_args=[], config={:behavior=>:invoke, :destination_root=>...) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/base.rb:485
#9 Rails::Generators.invoke(namespace="devise:install", args=[], config={:behavior=>:invoke, :destination_root=>...) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/bundler/gems/rails-958af5235874/railties/lib/rails/generators.rb:263
#10 Rails::Command::GenerateCommand#generate(#arg_rest=nil) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/bundler/gems/rails-958af5235874/railties/lib/rails/commands/generate/generate_command.rb:26
#11 Thor::Command#run(instance=#<Rails::Command::GenerateCommand:0x0000..., args=["devise:install"]) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/command.rb:27
#12 Thor::Invocation#invoke_command(command=#<struct Thor::Command name="generate", ..., args=[["devise:install"]]) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor/invocation.rb:127
#13 #<Class:Thor>#dispatch(meth="generate", given_args=["devise:install"], given_opts=nil, config={:current_command=>#<struct Thor::Comman...) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.1.0/lib/thor.rb:392
#14 #<Class:Rails::Command::Base>#perform(command="generate", args=[], config={:current_command=>#<struct Thor::Comman...) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/bundler/gems/rails-958af5235874/railties/lib/rails/command/base.rb:87
#15 Rails::Command.invoke(full_namespace="generate", args=[], config={:current_command=>#<struct Thor::Comman...) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/bundler/gems/rails-958af5235874/railties/lib/rails/command.rb:48
#16 <main> at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/bundler/gems/rails-958af5235874/railties/lib/rails/commands.rb:18
#17 [C] Kernel#require at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/bootsnap-1.9.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:23
#18 block in require_with_bootsnap_lfi at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/bootsnap-1.9.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:23
#19 Bootsnap::LoadPathCache::LoadedFeaturesIndex#register(short="rails/commands", long="/Users/k.nakama/.rbenv/versions/3.1.0/l...) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/bootsnap-1.9.3/lib/bootsnap/load_path_cache/loaded_features_index.rb:100
#20 Kernel#require_with_bootsnap_lfi(path="rails/commands", resolved="/Users/k.nakama/.rbenv/versions/3.1.0/l...) at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/bootsnap-1.9.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22
#21 Kernel#require(path="rails/commands") at ~/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/bootsnap-1.9.3/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:31
#22 <main> at bin/rails:5
(rdbg)
ステップオーバー(next)
ブレイクポイントで止まった状態でnもしくはnextを入力する。
メソッド内部には入らない。
ステップイン(step)
ブレイクポイントで止まった状態でstepを入力する
メソッド内部に入る。
ウォッチャ(display)
ブレイクポイントで止まった状態でdisplay 確認したい変数orクラスなどを入力する
undisplayで登録したdisplayをすべて解除。
undisplay 番号で指定番号のdisplay解除
gemのコードを修正したのを元に戻す
bundle pristine
参考