callOnEachEvent throws if eventTypes is null

[chmac]

I read the code here:

zulip-js/src/events_wrapper.js

Line 42 in cee3387

async function callOnEachEvent(callback, eventTypes = null) {

I assume that the second parameter was optional, but omitting it produced a firehose of errors. Adding it back as an empty array stopped the errors. I'd be happy to submit a PR switching null to [] if that's helpful. Seems like null is not a valid value.

[chmac]

I think this is because api doesn't filter out undefined or null as values. This library relies on isomoprhic-form-data, which is no longer required, and is recommended to be deprecated here and here. From my investigation, it seems like isomorphic-form-data chokes on undefined or null as a value.

[chmac]

I wrote a PR that addresses this in my case at least. I found this issue because I couldn't find a list of possible values for the eventTypes parameter. The only example I saw was ["messages"]. By now I found reaction and presence as other types. But to do that, I had to patch the package.