Stop Rails IRB and debugger sharing history

Question

Since I moved to Rails 7.1 and Ruby 3, I am struggling to use the Rails console history.

Previously, the console kept its own history, and the debugger history was separate. So if I was debugging a service called DoSomething, the debugger commands to (c)ontinue, (n)ext etc would not be part of the history of console commands.

Now I have a console history that looks like this.

DoSomething.call(param)
n
n
n
n
n
c

... and I have to key up 6 times to use DoSomething.call(param).

Any ideas how to separate out the history?

I have tried to set separate filenames for .rbdg_history, .irb_history, but I am not clear which of IRB, Pry, Debug and Rbdg I am using in the first place. Is the console IRB? I would be grateful if I could get a short summary of what's actually under the hood of Rails console.

I'm on Mac using rbenv.

Answer 1

This is not quite a complete solution, but it shows what has to happen to separate the two histories. The main problem is the shared Reline::HISTORY which is modified during debug session, when you exit, this history is written to .rdbg_history file and then because we're in irb as well it gets saved into .irb_history.

We have to restore history when we're done debugging:

(after this line) https://github.com/ruby/debug/blob/v1.9.1/lib/debug/console.rb#L200

  diff --git a/lib/debug/console.rb b/lib/debug/console.rb
  index b228086..a162324 100644
  --- a/lib/debug/console.rb
  +++ b/lib/debug/console.rb
  @@ -198,6 +198,8 @@ module DEBUGGER__
                 end
               }
             }
  +
  +          history.slice!(@init_history_lines..-1)
           end
         end
       end

Another problem is on exit that code doesn't run until after irb saves its history, which is too late. One way I found is to run it manually:

DEBUGGER__::SESSION.deactivate

---

Example:

$ rm ~/.irb_history ~/.rdbg_history
$ irb

# truncated output for clarity

>> require "debug"
>> debugger

(ruby) puts "from debug"
(rdbg) c    # continue command

>> DEBUGGER__::SESSION.deactivate
>> puts "from irb"
>> exit

$ cat ~/.irb_history      
require "debug"
debugger
puts "from irb"
exit

$ cat ~/.rdbg_history 
puts "from debug"
c
DEBUGGER__::SESSION.deactivate