Update Nijato Extensions to cancel suspend Calls silently

[cwliu]

Feature request

Type

Improvement - make what we have better

Is your feature request related to a problem?

After the suspending functionality PR, a Call.Failure will be returned even if it's from a Kotlin CancellationException:

suspend inline fun <reified T> Api.callAsync(crossinline receiver: suspend Api.() -> T): Call<T> = try {
    Call.Success(receiver(this))
} catch (throwable: Throwable) {
    Call.Failure(throwable)
}

that means callers need to handle this canceled result to prevent some error popup might be presented to users unexpectedly.

Describe the solution you'd like

Rethrow CancellationException to the caller, and this CancellationException will be ignored by the coroutines' exception handlers.

suspend inline fun <reified T> Api.callAsync(crossinline receiver: suspend Api.() -> T): Call<T> = try {
    Call.Success(receiver(this))
} catch (throwable: Throwable) {
+   if (throwable is CancellationException) {
+      throw throwable
+   }
    Call.Failure(throwable)
}

The benefits of this change

1. Can reduce the boilerplate code
2. Caller won't forget to handle the cancellation result from Call.Failure(throwable)

Additional context

Rethrow CancellationException might be a normal practice on Coroutines. I found these articles

... we catch CancellationException just to execute some actions when a coroutine has been cancelled, but we throw it again to avoid stopping the cancellation.
... in case you want to catch a generic Exception, you should remember to rethrow it in case its actual type is CancellationException otherwise you’ll also suppress the cancellation of coroutines.

from Kotlin Coroutines in Android — Part 5

... Do note that if something throws CancellationException you are generally expected to rethrow it so upstream objects are notified about the cancellation

from How to ignore JobCancellationException?

Also, this one is related to our topic. Kotlin: How to bypass CancellationException

[Unlimity]

Hi @cwliu ! Thanks for your suggestions. It seems reasonable enough. Want to put up a pull request? :)