Catching node.js errors?

Question

JavaScript

For some reason, the program falls off without any errors in the logs. I catch fatal errors and exit events like this:

[
   'exit',
   'SIGINT',
   'SIGTERM',
   'SIGBREAK'
].forEach(event =>
{
   process.on(event, () =>
   {
      Cleanup(event)
   })
})

process.on('uncaughtException\n', err =>
{
   console.error('Неотловленная ошибка', err.message, err.stack)
})

process.on('unhandledRejection\n', (reason, promise) =>
{
   console.error('Ошибка unhandledRejection', reason)
})

But sometimes I just get a message from the Cleanup function that the completion was called and the exit event. exitCode is undefined. Because the program is launched through forever, then this leads to a cyclic restart.
node.js v8.4.0
npm 5.3.0
Debian 7.11