# File lib/rubygems/source_index.rb, line 283
  def outdated
    dep = Gem::Dependency.new '', Gem::Requirement.default

    remotes = Gem::SourceInfoCache.search dep, true

    outdateds = []

    latest_specs.each do |local|
      name = local.name
      remote = remotes.select { |spec| spec.name == name }.
        sort_by { |spec| spec.version.to_ints }.
        last

      outdateds << name if remote and local.version < remote.version
    end

    outdateds
  end