Repository navigation
binding.irb fails when used in BasicObject-derived class #1114
Description
Description
I expected that binding.irb would start an interactive session regardless of execution context's class. However, that is not the case, as IRB can't be found when called in BasicObject. Though, this behavior is inconsistent and depends both on Ruby version and irb version.
This script consistently reproduces the problem for me on Ruby 3.3.9, but not 3.2.9:
#!/usr/bin/env ruby
# frozen_string_literal: true
require "irb"
class A < Object
def irb
::Kernel.binding.irb
end
end
class B < BasicObject
def irb
::Kernel.binding.irb
end
end
class C < BasicObject
define_method(:binding, ::Kernel.instance_method(:binding))
def irb
binding.irb
end
end
# A.new.irb # works
# B.new.irb # uninitialized constant B::IRB (NameError)
C.new.irb # uninitialized constant C::IRB (NameError)$ ruby -v
ruby 3.3.9 (2025-07-24 revision f5c772fc7c) [x86_64-linux]
$ ruby irb_test.rb
irb_test.rb:22:in `irb': uninitialized constant C::IRB (NameError)It seems to work on Ruby 3.2:
$ ruby -v
ruby 3.2.9 (2025-07-24 revision 8f611e0c46) [x86_64-linux]
$ ruby irb_test.rb
From: irb_test.rb @ line 22 :
17:
18: class C < BasicObject
19: define_method(:binding, ::Kernel.instance_method(:binding))
20:
21: def irb
=> 22: binding.irb
23: end
24: end
25:
26: # A.new.irb # works
27: # B.new.irb # uninitialized constant B::IRB (NameError)Result of irb_info
irb(main):001> irb_info
Ruby version: 3.3.9
IRB version: irb 1.13.1 (2024-05-05)
InputMethod: RelineInputMethod with Reline 0.5.10
Completion: Autocomplete, RegexpCompletor
RUBY_PLATFORM: x86_64-linux
LANG env: en_US.utf-8
East Asian Ambiguous Width: 1
Terminal Emulator
What's your terminal emulator?
- Doesn't matter, but happens in e.g. Tilda.
Setting Files
Are you using ~/.irbrc and ~/.inputrc?
- No.
Activity
trinistr commentedon Jul 30, 2025
Oops, just noticed that I wasn't using the latest version of "irb" gem. This no longer fails with 1.15.2. Even though there aren't any changes in
Binding#irbbetween them.tompng commentedon Nov 19, 2025
Fixed in #1031