Gem::QueryUtils#spec_platforms

# File tmp/rubies/ruby-4.1.0-preview1/lib/rubygems/query_utils.rb, line 360
def spec_platforms(entry, platforms)
  platforms = platforms.transform_values(&:uniq)
  non_ruby = platforms.any? do |_, pls|
    pls.any? {|pl| pl != Gem::Platform::RUBY }
  end

  return unless non_ruby

  if platforms.length == 1
    title = platforms.values.first.length == 1 ? "Platform" : "Platforms"
    entry << "    #{title}: #{platforms.values.sort.join(", ")}\n"
  else
    entry << "    Platforms:\n"

    sorted_platforms = platforms.sort

    sorted_platforms.each do |version, pls|
      label = "        #{version}: "
      data = format_text pls.sort.join(", "), 68, label.length
      data[0, label.length] = label
      entry << data << "\n"
    end
  end
end