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Unhandled "error" event. (Error: Callback called multiple times)

See original GitHub issue

Please tell us about your environment:

winston version?
- winston@2
- winston@3
node -v outputs: 8.16.1
Operating System? Linux
Language? TypeScript 3.6.3

What is the problem?

Sometimes, consistently, some of the calls to log results in the following error:

Unhandled "error" event. (Error: Callback called multiple times)
      at DerivedLogger.afterTransform (./node_modules/winston/node_modules/readable-stream/lib/_stream_transform.js:82:17)
      at DerivedLogger._transform (./node_modules/winston/lib/winston/logger.js:310:7)
      at DerivedLogger.Object.<anonymous>.Transform._read (./node_modules/winston/node_modules/readable-stream/lib/_stream_transform.js:177:10)
      at DerivedLogger.Object.<anonymous>.Transform._write (./node_modules/winston/node_modules/readable-stream/lib/_stream_transform.js:164:83)
      at doWrite (./node_modules/winston/node_modules/readable-stream/lib/_stream_writable.js:405:139)
      at writeOrBuffer (./node_modules/winston/node_modules/readable-stream/lib/_stream_writable.js:394:5)
      at DerivedLogger.Object.<anonymous>.Writable.write (./node_modules/winston/node_modules/readable-stream/lib/_stream_writable.js:303:11)
      at DerivedLogger.log (./node_modules/winston/lib/winston/logger.js:244:14)
      at DerivedLogger.(anonymous function) [as verbose] (./node_modules/winston/lib/winston/create-logger.js:95:19)

I’ve not figured out the pattern of why it fails yet.

What do you expect to happen instead?

I expect it to throw a more useful error that would help me to identify what I’m doing wrong.

Other information

It felt related to ExceptionHandler problems at https://github.com/winstonjs/winston/pull/1355 https://github.com/winstonjs/winston/issues/1289 https://github.com/winstonjs/winston/issues/1261 https://github.com/winstonjs/winston/issues/511, but after few experiments doesn’t so:

I have both file and console transports, but commenting out either of two doesn’t change the behaviour.
commenting out all my custom formatting didn’t change the behaviour (except that succeeding logs looked very different now)
From hacky-debug console logs I see that message and meta are very “casual” and similar to other succeeding cases.