[ruby/reline] Treat prompt correctly when Reline.prompt_proc isn't set
https://github.com/ruby/reline/commit/9c9ba0eff3
[ruby/reline] Treat prompt correctly when Reline.prompt_proc isn't set
https://github.com/ruby/reline/commit/9c9ba0eff3