WithTimeout wont stop timed-out tasks

[pcampbell83]

Hi, looking at the implementation -- won't the net result be that; the task itself will not stop running even if the timeout succeeds first?

Is that intentional?

[mjfreelancing]

I agree. Even if the caller checks the return result against default this is no indication the task timed out because the running task may actually return null if T is a reference type. And yes, if the delay task completes first then the original task will remain running.

The only way to do this correctly is for the caller to use a CancellationTokenSource and have this cancelled if the delay task completes first. It's then up to the caller to handle this situation within their own logic by checking IsCancellationRequested on the CancellationToken.

https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/concepts/async/cancel-remaining-async-tasks-after-one-is-complete

https://docs.microsoft.com/en-us/dotnet/api/system.threading.cancellationtoken.iscancellationrequested?view=netframework-4.8