Gem::RemoteFetcher#fetch_path

# File tmp/rubies/ruby-3.1.3/lib/rubygems/remote_fetcher.rb, line 241
def fetch_path(uri, mtime = nil, head = false)
  uri = Gem::Uri.new uri

  unless uri.scheme
    raise ArgumentError, "uri scheme is invalid: #{uri.scheme.inspect}"
  end

  data = send "fetch_#{uri.scheme}", uri, mtime, head

  if data && !head && uri.to_s.end_with?(".gz")
    begin
      data = Gem::Util.gunzip data
    rescue Zlib::GzipFile::Error
      raise FetchError.new("server did not return a valid file", uri)
    end
  end

  data
rescue Timeout::Error, IOError, SocketError, SystemCallError,
       *(OpenSSL::SSL::SSLError if Gem::HAVE_OPENSSL) => e
  raise FetchError.new("#{e.class}: #{e}", uri)
end