JS Coroutine started as undispatched, why?

[lppedd]

Hey there!
I was just wondering what's the rationale for starting the coroutine as UNDISPATCHED, instead of keeping the default behavior.

kotlin-suspend-transform-compiler-plugin/runtime/suspend-transform-runtime/src/jsMain/kotlin/love.forte.plugin.suspendtrans/runtime/RunInSuspendJs.kt

Line 20 in 88b1bb5

return CoroutineScope4Js.promise(start = CoroutineStart.UNDISPATCHED) { block() }

[ForteScarlet]

Hello!
To be honest, I can't quite remember exactly why I wrote that. The "me now" guesses that the "me then" was probably because I read Deferred<T>.asPromise():

https://github.com/Kotlin/kotlinx.coroutines/blob/f227432328afe41505a62a9fa6ee9d12ae6aab80/kotlinx-coroutines-core/js/src/Promise.kt#L50-L57

used UNDISPATCHED, so I followed suit.

Probably no deep reason 😂

[lppedd]

This is the commit that added UNDISPATCHED
Kotlin/kotlinx.coroutines@03a266a

Beware however that it's for converting a Promise to a Deferred, and not the other way, so I'm not sure the same "logical rules" apply.
That's interesting tho, I guess in the JS world it doesn't change much? We only have a single thread.

[lppedd]

This is the release notes for the UNDISPATCHED change.
https://github.com/Kotlin/kotlinx.coroutines/releases/tag/0.21.1

[ForteScarlet]

https://github.com/Kotlin/kotlinx.coroutines/releases/tag/0.21.1

It seems to mention "'Unhandled promise rejection' warning", maybe it has something to do with something in node, but I don't know node very well so I'm not too sure about more specific details