Gem::Source#load_marshal_specs

# File tmp/rubies/ruby-4.1.0-preview1/lib/rubygems/source.rb, line 311
def load_marshal_specs(type)
  file       = FILES[type]
  fetcher    = Gem::RemoteFetcher.fetcher
  file_name  = "#{file}.#{Gem.marshal_version}"
  spec_path  = enforce_trailing_slash(uri) + "#{file_name}.gz"
  cache_dir  = cache_dir spec_path
  local_file = File.join(cache_dir, file_name)
  retried    = false

  if update_cache?
    require "fileutils"
    FileUtils.mkdir_p cache_dir
  end

  spec_dump = fetcher.cache_update_path spec_path, local_file, update_cache?

  Gem.load_safe_marshal
  begin
    Gem::NameTuple.from_list Gem::SafeMarshal.safe_load(spec_dump)
  rescue ArgumentError
    if update_cache? && !retried
      FileUtils.rm local_file
      retried = true
      retry
    else
      raise Gem::Exception.new("Invalid spec cache file in #{local_file}")
    end
  end
end