Errors in tests appearing for Node.js >= v10.14.2

[jaydenseric]

Something that changed between Node.js v10.14.1 and v10.14.2 has caused errors to log in a few places in tests (which still pass):

https://travis-ci.org/jaydenseric/graphql-upload/jobs/477605581#L570

Error: Parse Error
      at socketOnEnd (_http_server.js:455:20)
      at Socket.emit (events.js:193:15)
      at Socket.EventEmitter.emit (domain.js:459:23)
      at endReadableNT (_stream_readable.js:1129:12)
      at process.internalTickCallback (internal/process/next_tick.js:72:19)

We need to work out if its a bug in Node.js, or a graphql-upload compatibility issue with the new Node.js versions.

[jaydenseric]

These Node.js changes may be related?

• [cb861a4897] - stream: do not error async iterators on destroy(null) (Matteo Collina) #23901
• [6f4a638175] - stream: ended streams should resolve the async iteration (Matteo Collina) #23901
• [ce79ae6544] - stream: async iteration should work with destroyed stream (Matteo Collina) #23785

[mike-marcacci]

Just looking at changes in node, this may be related. I think the first thing to do is figure out where these are being logged. I do remember having to wrestle tap at one point to keep it from logging expected errors, so this may be something like an unhandled error event or Promise rejection that tap is helpfully bringing to our attention.

The actual error that is logged is not surprising to see, as we are aborting the request in those tests. I know that between node 8, 9, and 10, errors would appear in the stream's pieces in different orders, so we already have logic that covers a broad range of timings. My initial suspicion is that node made a very subtle change, and we know about (and handle) an error before we would attach an error handler to a downstream piece that previously wasn't propagated the error, but now is.