gistfile1.rb

class Gem::Dependency
  def to_bundler
    args = []
    args << name
    args << specification.version.to_s if specification.version.to_s.present?
    options = {}
    options[:require_as] = lib if lib.present?
    str = "gem '#{args.join "', '"}'"
    str << ", #{options.inspect.gsub(/[\{\}]/, '')}" if options.present?
    str
  end
end

Rails.configuration.gems.each { |g| puts g.to_bundler }