How to use 'debugger' and 'pry' when developing a gem? (Ruby)

Question

I'm developing a gem, and my Gemfile looks like this:

source :rubygems

gemspec

group :development, :test do
  gem "pry"
  gem "debugger"
  gem "rake"
end

However, I don't want people to have to install pry and debugger when running tests, but I also want to be able to require them in my tests (because I'm running tests prefixed with bundle exec, and I cannot get it them in my load path if they're not in the Gemfile). How do I achieve this?

Also, when to put gems that I use for development in the gemspec, and when to put them in the Gemfile? I really don't know the difference.

Answer 1

You can add gems to your gemspec as a development dependency, like this:

Gem::Specification.new do |s|
  # ...
  s.add_development_dependency 'pry'
  s.add_development_dependency 'debugger'
  s.add_development_dependency 'rake'
end

These will only be installed when working on the gem and not when installing the gem itself.