cannot catch ENOENT when non-node spawn is missing

[jdmairs]

So I'm using forever-monitor to spawn a c++ executable. It works great. I then purposefully delete the executable to test my error handling in Express.

export async function startProcess(): Promise<void> {
  return new Promise((resolve, reject) => {
    const child = forever.start(['./Foo'], {
      max: 1,
    });
    child.on('exit', () => {
      getLogger('NewJobNanny').info('Foo has exited gracefully');
      resolve();
    });

    child.on('stdout', (data: any) => {
      getLogger('NewJobNanny').info('Detecting stdout ', data);
    });

    child.on('error', (error) => {
      getLogger('NewJobNanny').error('startProcess detected error: ', error);
      reject(error);
    });
  });

I have a catch on startProcess but it does not catch. Instead my node/express app crashes with the following

events.js:200 throw er; // Unhandled 'error' event ^

Error: spawn ./Foo ENOENT at Process.ChildProcess._handle.onexit (internal/child_process.js:264:19) at onErrorNT (internal/child_process.js:456:16) at processTicksAndRejections (internal/process/task_queues.js:81:21) Emitted 'error' event on ChildProcess instance at: at Process.ChildProcess._handle.onexit (internal/child_process.js:270:12) at onErrorNT (internal/child_process.js:456:16) at processTicksAndRejections (internal/process/task_queues.js:81:21) { errno: 'ENOENT', code: 'ENOENT', syscall: 'spawn ./Foo', path: './Foo', spawnargs: [] }