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EventEmitter interface inconsistent

See original GitHub issue

Describe the bug

EventEmitter interface is based on NodeJS events module.

core-event-emitter module returns custom EventEmitter class which does not implement interface and native emitter is not accessible (private).

So, it’s possible to have the following error when calling native emitter functions not implemented by custom emitter:

(node:89665) UnhandledPromiseRejectionWarning: TypeError: is not a function

To Reproduce In my example I tried to call the off function of native emitter.

Expected behavior Either a typescript error must be thrown at compile time. Or off function of native emitter is available on custom class Or all native emitter function are available.

I can make the fix asap after best solution has been chosen:

  • re-write EventEmitter interface with custom class methods
  • add off method to custom class
  • expose native emitter from custom class.

Issue Analytics

  • State:closed
  • Created 4 years ago
  • Comments:5 (2 by maintainers)

github_iconTop GitHub Comments

faustbriancommented, Apr 16, 2019

If you encounter an issue and already have a solution just submit a PR with it otherwise small issues like that will just be resolved.

dlecancommented, Apr 16, 2019

@faustbrian thank you for fixing this quickly.

It would have been also great to discuss it a little bit more before.

1/ The done “bugfix” doesn’t really fix the underlying issue: the Ark emitter.EventEmitter type is not a NodeJS events.EventEmitter and several other methods are missing, such as removeAllListeners, listeners, addListener … These methods used to be available with eventemitter3, removed by #2329, which have introduced an API breaking change and have impacted our Unik-Name implementation of Ark core (see

Another solution: emitter.EventEmitter could inherit from events.EventEmitter and override a few methods to update the max count of listeners.

2/ @nigui had already done a private fix when he described the issue. So a fix for this issue has been done twice. This can bee seen as “lost time”. Was this issue critical enough to fix it so quickly (5h)?

So, for the next time, can you please tell us:

  • either Ark team is not interested in external contributions
  • or interested by Github’s PRs with some code, without discussing

Thank you

Read more comments on GitHub >

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