Gem::QueryUtils#entry_versions

# File tmp/rubies/ruby-3.1.3/lib/rubygems/query_utils.rb, line 241
def entry_versions(entry, name_tuples, platforms, specs)
  return unless options[:versions]

  list =
    if platforms.empty? || options[:details]
      name_tuples.map {|n| n.version }.uniq
    else
      platforms.sort.reverse.map do |version, pls|
        out = version.to_s

        if options[:domain] == :local
          default = specs.any? do |s|
            !s.is_a?(Gem::Source) && s.version == version && s.default_gem?
          end
          out = "default: #{out}" if default
        end

        if pls != [Gem::Platform::RUBY]
          platform_list = [pls.delete(Gem::Platform::RUBY), *pls.sort].compact
          out = platform_list.unshift(out).join(" ")
        end

        out
      end
    end

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