class Puma::Server

def lowlevel_error(e, env, status=500)
  if handler = @options[:lowlevel_error_handler]
    if handler.arity == 1
      return handler.call(e)
    elsif handler.arity == 2
      return handler.call(e, env)
    else
      return handler.call(e, env, status)
    end
  end
  if @leak_stack_on_error
    backtrace = e.backtrace.nil? ? '<no backtrace available>' : e.backtrace.join("\n")
    [status, {}, ["Puma caught this error: #{e.message} (#{e.class})\n#{backtrace}"]]
  else
    [status, {}, [""]]
  end
end