Script to bump Ruby version in Rails app
Any time I need to bump a Ruby version in a Rails repo,
I need to find which files
have hardcoded references to the version.
The 3 files that usually have hardcoded versions are
Dockerfile, Gemfile and .tool-versions.
I wrote a script to automate
Ruby version bumps by putting this
in bin/bumpruby:
#!/usr/bin/env ruby
unless (new_version = ARGV[0])
puts "💥 Usage: bin/bumpruby <version>"
return
end
system("asdf install ruby #{new_version}")
system("asdf shell ruby #{new_version}")
puts "\n⭐️ Switched to ruby #{new_version}"
def bump_ruby_version(file_name, pattern, replacement)
content = File.read(file_name)
new_content = content.gsub(pattern, replacement)
File.write(file_name, new_content)
puts "⭐️ Replaced version in #{file_name}"
end
bump_ruby_version(".tool-versions", /ruby \d+\.\d+\.\d+/, "ruby #{new_version}")
bump_ruby_version("Dockerfile", /ARG RUBY_VERSION=\d+\.\d+\.\d+/, "ARG RUBY_VERSION=#{new_version}")
bump_ruby_version("Gemfile", /ruby "\d+\.\d+\.\d+"/, "ruby \"#{new_version}\"")
puts "⭐️ Bundle install"
system("bundle install")
puts "⭐️ Running tests"
system("bin/rails test")
Now we can use it like this to bump to Ruby 3.3.3:
bin/bumpruby 3.3.3
Usually when minor Ruby versions are released, it’s because there’s an important bug or vulnerability fix, so it makes sense to upgrade right away. I have a couple of toy apps deployed to fly.io that I don’t touch very often. Having a command to do that means I’m less likely to procrastinate when it comes to version bumps.