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Hi, I'm trying to confirm something: When I call Job.join() are regular exceptions rethrown? I would expect them to be, but the documentation says:
&gt; This invocation resumes normally (without exception) when the job is complete for any reason and the Job of the invoking coroutine is still active.

No the exception is sent to the exception handler of the coroutine.

<https://kotlinlang.org/docs/exception-handling.html#exception-propagation>

On Android it will cause a crash on the JVM it will print to console. I believe it crashes on iOS also.

Now on Android, I think the viewModelScope is configured to handle the exception and not crash

~That's wrong. `Job.join()` will see the exception.~

<https://play.kotlinlang.org/#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|Playground example>.

`Job.join()` does not rethrow the exception with which the `Job` finished. That said, because it's a `suspend` function, it *will* throw a `CancellationException` if the *caller* is cancelled.

Oliver's example throws an exception because `job1` is the child of `coroutineScope`, its failure cancels the `coroutineScope`, and therefore, the computation in the `coroutineScope` gets cancelled as well.

If a `Job` fails independently from the `join` caller (e.g., they have unrelated coroutine scopes), then no exception will be thrown! <https://pl.kotl.in/Bis4BithQ> is an example.