Consolidate error handling across different sorts of Actions

Currently an exception thrown in a coroutine (a method returning either IEnumerable<IResult>, Task or Task<>) when invoked through Message.Attach has it’s exceptions handled in Coroutine, any exceptions would appear in Coroutine.Completed.

This also affects the event aggregator with IHandleWithCoroutine and IHandleWithTask.

I consider this a potential issue because of the following

// Exception raised in Application.UnhandledException.
public void SampleMethod() { throw new InvalidOperationException(); }

// Exception raised in Coroutine.Completed
public Task SampleMethod() { throw new InvalidOperationException(); }

We could resolve this in two ways.

1. Have Coroutine.Completed raise an unhandled exception event.
2. Have Coroutine.Completed throw an exception on error.
3. Do nothing but add some documentation.

If there is any change I’d like to get this into 3.0.0 as it suddenly cause new exceptions if they were previously being swallowed.

Thoughts?

[soltrac]

Any idea when is this going to be handled?

[nigel-sampson]

Just posted a reply on the question, while it doesn’t look to be caused by this it certainly has something to consider when doing this work.

Ideally I think making the error handling separate from any current event means we can pipe all of the errors to the same place.