for_lockfile

# File lib/rubygems/requirement.rb, line 154
  def for_lockfile # :nodoc:
    return if [DefaultRequirement] == @requirements

    list = requirements.sort_by { |_, version|
      version
    }.map { |op, version|
      "#{op} #{version}"
    }.uniq

    " (#{list.join ', '})"
  end