source "https://rubygems.org" gemspec gem 'rake' rails = ENV['RAILS'] || '4-0-stable' gem 'arel' case rails when /\// # A path gem 'activesupport', :path => "#{rails}/activesupport" gem 'activemodel', :path => "#{rails}/activemodel" gem 'activerecord', :path => "#{rails}/activerecord" gem 'actionpack', :path => "#{rails}/activerecord" when /^v/ # A tagged version git 'git://github.com/rails/rails.git', :tag => rails do gem 'activesupport' gem 'activemodel' gem 'activerecord' gem 'actionpack' end else git 'git://github.com/rails/rails.git', :branch => rails do gem 'activesupport' gem 'activemodel' gem 'activerecord' gem 'actionpack' end if rails == '3-0-stable' gem 'mysql2', '< 0.3' end end