Issue #21723 has been updated by osyoyu (Daisuke Aritomo). Here is a patch: https://github.com/ruby/ruby/pull/15373 ---------------------------------------- Bug #21723: `binding.irb` raises a LoadError under `bundle exec` https://bugs.ruby-lang.org/issues/21723#change-115414 * Author: osyoyu (Daisuke Aritomo) * Status: Open * ruby -v: ruby 4.0.0preview2 (2025-11-17 master 4fa6e9938c) +PRISM [arm64-darwin24] * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- In Ruby 4.0, `binding.irb` raises a LoadError when some unknown condition is met. ```ruby # main.rb binding.irb ``` ``` main.rb:1: warning: irb used to be loaded from the standard library, but is not part of the default gems since Ruby 4.0.0. You can add irb to your Gemfile or gemspec to fix this error. Failed to activate irb, please install it with 'gem install irb' /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'Kernel.require': cannot load such file -- irb (LoadError) Did you mean? erb from /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'block (2 levels) in Kernel#replace_require' from main.rb:1:in 'Binding#irb' from main.rb:1:in '<main>' /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'Kernel.require': cannot load such file -- irb (LoadError) Did you mean? erb from /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'block (2 levels) in Kernel#replace_require' from main.rb:1:in 'Binding#irb' from main.rb:1:in '<main>' ``` While irb has been changed to a bundle gem in #20309, it is agreed that `binding.irb` shall work under `bundle exec` without adding `irb` in Gemfile. Thus, I've considered this behavior as an bug and created a ticket here. One condition I have discovered is when the Gemfile contains a `gem` reference with a `path:` option. I have created a repro repository in https://github.com/osyoyu/irbfail for that case. -- https://bugs.ruby-lang.org/

Issue #21723 has been updated by osyoyu (Daisuke Aritomo). I have discovered that this issue reproduces when Gemfile contains a gem referred by `path:` or `git:`. Such Gemfiles are pretty much common in real-world applications including Rails, which use in-house Gems and libraries, like this: ```ruby # binding.irb will fail under this Gemfile gem "some-inhouse-gem", git: 'https://github.com/our-company/some-inhouse-gem.git' ``` Can the patch visited before Ruby 4.0 release? ---------------------------------------- Bug #21723: `binding.irb` raises a LoadError under `bundle exec` when Gemfile contains `path:` or `git:` https://bugs.ruby-lang.org/issues/21723#change-115678 * Author: osyoyu (Daisuke Aritomo) * Status: Assigned * Assignee: hsbt (Hiroshi SHIBATA) * ruby -v: ruby 4.0.0preview2 (2025-11-17 master 4fa6e9938c) +PRISM [arm64-darwin24] * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- In Ruby 4.0, `binding.irb` raises a LoadError when some unknown condition is met. ```ruby # main.rb binding.irb ``` ``` main.rb:1: warning: irb used to be loaded from the standard library, but is not part of the default gems since Ruby 4.0.0. You can add irb to your Gemfile or gemspec to fix this error. Failed to activate irb, please install it with 'gem install irb' /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'Kernel.require': cannot load such file -- irb (LoadError) Did you mean? erb from /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'block (2 levels) in Kernel#replace_require' from main.rb:1:in 'Binding#irb' from main.rb:1:in '<main>' /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'Kernel.require': cannot load such file -- irb (LoadError) Did you mean? erb from /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'block (2 levels) in Kernel#replace_require' from main.rb:1:in 'Binding#irb' from main.rb:1:in '<main>' ``` While irb has been changed to a bundle gem in #20309, it is agreed that `binding.irb` shall work under `bundle exec` without adding `irb` in Gemfile. Thus, I've considered this behavior as an bug and created a ticket here. One condition I have discovered is when the Gemfile contains a `gem` reference with a `path:` option. I have created a repro repository in https://github.com/osyoyu/irbfail for that case. -- https://bugs.ruby-lang.org/

Issue #21723 has been updated by hsbt (Hiroshi SHIBATA). Status changed from Assigned to Closed Backport changed from 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN to 3.2: DONTNEED, 3.3: DONTNEED, 3.4: DONTNEED, 4.0: REQUIRED I created backport PR for Ruby 4.0: https://github.com/ruby/ruby/pull/15881 ---------------------------------------- Bug #21723: `binding.irb` raises a LoadError under `bundle exec` when Gemfile contains `path:` or `git:` https://bugs.ruby-lang.org/issues/21723#change-116143 * Author: osyoyu (Daisuke Aritomo) * Status: Closed * Assignee: hsbt (Hiroshi SHIBATA) * ruby -v: ruby 4.0.0preview2 (2025-11-17 master 4fa6e9938c) +PRISM [arm64-darwin24] * Backport: 3.2: DONTNEED, 3.3: DONTNEED, 3.4: DONTNEED, 4.0: REQUIRED ---------------------------------------- In Ruby 4.0, `binding.irb` raises a LoadError when some unknown condition is met. ```ruby # main.rb binding.irb ``` ``` main.rb:1: warning: irb used to be loaded from the standard library, but is not part of the default gems since Ruby 4.0.0. You can add irb to your Gemfile or gemspec to fix this error. Failed to activate irb, please install it with 'gem install irb' /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'Kernel.require': cannot load such file -- irb (LoadError) Did you mean? erb from /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'block (2 levels) in Kernel#replace_require' from main.rb:1:in 'Binding#irb' from main.rb:1:in '<main>' /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'Kernel.require': cannot load such file -- irb (LoadError) Did you mean? erb from /Users/osyoyu/.rbenv/versions/master/lib/ruby/4.0.0+0/bundled_gems.rb:60:in 'block (2 levels) in Kernel#replace_require' from main.rb:1:in 'Binding#irb' from main.rb:1:in '<main>' ``` While irb has been changed to a bundle gem in #20309, it is agreed that `binding.irb` shall work under `bundle exec` without adding `irb` in Gemfile. Thus, I've considered this behavior as an bug and created a ticket here. One condition I have discovered is when the Gemfile contains a `gem` reference with a `path:` option. I have created a repro repository in https://github.com/osyoyu/irbfail for that case. -- https://bugs.ruby-lang.org/