any tips on how to debug this? it's a class cast ...

# javascript

[Bernhard]

any tips on how to debug this?

it's a class cast exception inside a coroutine that I have no clue how to debug; coroutines in general seem to rewrite the code in such a fashion that I can not find the originating issue

Edit: I placed the following thing into webpack.config.d:

config["mode"] = 'development'

[Edoardo Luppi]

Just wondering how that config change made it work tho...

[Bernhard]

I was able to somehow figure out where the exception was thrown

[Edoardo Luppi]

Ah, so basically you got cleaner code spit out

[Bernhard]

yeah, debugging class cast exceptions seems incredibly bad

[Bernhard]

the minified code is basically unreadable

[Edoardo Luppi]

Agree. Was that your own issue or from the library?

[Bernhard]

library had type comments that said: returns Promise<Class>

[Bernhard]

I typed it as such and had a cast as well on a more specific class

[Bernhard]

turns out it returns Type | undefined (in certain cases)

[Edoardo Luppi]

Ahhh ok. Seems like something that tend to happen when interoping with JS libs.

[Bernhard]

I'm contemplating actually shipping unminified code to production because of that

[Bernhard]

1.6mb right now vs 160kb minified

[Edoardo Luppi]

I try to avoid JS dependencies as much as possible. If you can rewrite it in Kotlin without spending days on it, I'd go for it.

[Bernhard]

same here, but the thing I'm interacting with is a framework

[Bernhard]

think of it as something similar to Django but in JS

[Edoardo Luppi]

Ok then you're stuck with it. Typings are difficult to get right unfortunately.

[Bernhard]

yeah, basically

[Bernhard]

TS type definitions would have had the same issue and the ones I was using have been unmaintained for 2 years; it's just the class cast exceptions + coroutine continuations that really cause me grief

[turansky]

config["mode"] = 'development'

You can do it from Gradle DSL too

[turansky]

Also you can add special exception handler for coroutines.
It's WA for https://github.com/Kotlin/kotlinx.coroutines/issues/3978