pry: fails to launch with undefined method '=~' for class 'Pry::Code'

[matthiasbeyer]

Nixpkgs version

• Unstable (26.05)

Describe the bug

pry fails to start

Steps to reproduce

nix run github:nixos/nixpkgs/nixpkgs-unstable#pry

Expected behaviour

Startup succeeds, pry shell is spawned

Screenshots

No response

Relevant log output

/nix/store/7f2k9s65qwd7k2qswflljlsf84qimgpy-ruby3.4-pry-0.13.1/lib/ruby/gems/3.4.0/gems/pry-0.13.1/lib/pry/plugins.rb:3: warning: ostruct was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 4.0.0.
You can add ostruct to your Gemfile or gemspec to silence this warning.
/nix/store/7f2k9s65qwd7k2qswflljlsf84qimgpy-ruby3.4-pry-0.13.1/lib/ruby/gems/3.4.0/gems/pry-0.13.1/lib/pry/code.rb:342:in '<class:Code>': undefined method '=~' for class 'Pry::Code' (NameError)
	from /nix/store/7f2k9s65qwd7k2qswflljlsf84qimgpy-ruby3.4-pry-0.13.1/lib/ruby/gems/3.4.0/gems/pry-0.13.1/lib/pry/code.rb:32:in '<class:Pry>'
	from /nix/store/7f2k9s65qwd7k2qswflljlsf84qimgpy-ruby3.4-pry-0.13.1/lib/ruby/gems/3.4.0/gems/pry-0.13.1/lib/pry/code.rb:5:in '<top (required)>'
	from /nix/store/s57rf37r1i38kpm3nlv4h8f8z2w2n80d-ruby-3.4.8/lib/ruby/3.4.0/bundled_gems.rb:82:in 'Kernel.require'
	from /nix/store/s57rf37r1i38kpm3nlv4h8f8z2w2n80d-ruby-3.4.8/lib/ruby/3.4.0/bundled_gems.rb:82:in 'block (2 levels) in Kernel#replace_require'
	from /nix/store/7f2k9s65qwd7k2qswflljlsf84qimgpy-ruby3.4-pry-0.13.1/lib/ruby/gems/3.4.0/gems/pry-0.13.1/lib/pry.rb:70:in '<top (required)>'
	from /nix/store/s57rf37r1i38kpm3nlv4h8f8z2w2n80d-ruby-3.4.8/lib/ruby/3.4.0/bundled_gems.rb:82:in 'Kernel.require'
	from /nix/store/s57rf37r1i38kpm3nlv4h8f8z2w2n80d-ruby-3.4.8/lib/ruby/3.4.0/bundled_gems.rb:82:in 'block (2 levels) in Kernel#replace_require'
	from /nix/store/hcb3wr97z8vi57d5vw99vsid8xz2xcnl-pry-0.13.1/lib/ruby/gems/3.4.0/gems/pry-0.13.1/bin/pry:9:in '<top (required)>'
	from /nix/store/10kw4ari5mqlx1giq3xa9z5hrjbmk4pd-pry-0.13.1/bin/pry:35:in 'Kernel#load'
	from /nix/store/10kw4ari5mqlx1giq3xa9z5hrjbmk4pd-pry-0.13.1/bin/pry:35:in '<main>'

Additional context

Fails on stable (25.11) as well as on unstable

System metadata

• system: "x86_64-linux"
• host os: Linux 6.12.67, NixOS, 25.11 (Xantusia), 25.11.20260329.107cba9
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.31.2
• channels(m): ""
• channels(root): ""
• nixpkgs: /var/src/nixpkgs

Notify maintainers

@tckmn

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