Replace pry-byebug with ruby debug in generated Gemfile

[eoinkelly]

Motivations

• debug is installed by default on Ruby 3.1 but supports back to 2.6
• debug is the default in Rails and we should align with Rails defaults whenever possible
• there is an incompatibility between Zeitwork and byebug - see Depend on ruby/debug, replacing Byebug rails/rails#43187
• debug is part of ruby stdlib so will get new language features immediately
• debug apparently has good VSCode integration (I have not tested this)

Challenges

• It looks like the shortcuts are a bit different to byebug so it will break some muscle memory but I think it's worth the pain. https://st0012.dev/from-byebug-to-ruby-debug has a good comparison of the commands.

Mitigations

• A dev could backport this change pretty easily to an existing app if they don't want to remember both sets of shortcuts.

[eoinkelly]

Some more resources

• https://blog.testdouble.com/talks/2022-08-22-debugging-ruby-on-rails-with-vscode/

My experience with debug vs pry-byebug for a morning

++ is for ways it debug is better than pry-byebug, -- is for the reverse

• ++ debug has color output in backtraces
• ++ Backtrace in debug contains values of method call or block arguments
• ++ de bug has single letter commands by default
• -- new command shortcuts to learn
• ++ debug shows you the first two lines of backtrace when you drop into the debugger - handy
• ++ very expressive ways to drop into debugger - can watch ivars, stop on lines or class#method or based on conditional logic
• -- I had to install the iterm2 shell integration to make mouse scrolling work in debug (this might just be an iterm thing)
• ++ debug supports running things under Procfile like Rails 7 wants to do by default

[G-Rath]

I've put exactly zero effort into learning debug so maybe there's a flag or something I'm missing, but trying it out on my project where I'm just doing require "debug"; binding.break I've found that exceptions seem to cause the debugging to end whereas for binding.pry that doesn't happen.

In practical terms this missing if you trigger a "method missing" it'll exit your debugging session which is very annoying so I think we should have it on the list of things to ensure we understand (and ideally have addressed if possible)

[eoinkelly]

Hmmm I haven't hit that but I agree it would be annoying. Removing ready for dev label until we gather more experience on individual projects.