Observe a connect given up on - #875
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ViewerClient.IsOwned and the synchronous TrySend wait on ConnectAsync for a bounded time, inside a using. A connect given up on is still pending when the client is disposed, and faults once that tears it down - or, where the port refuses rather than hangs, when the refusal arrives - with nobody left to observe it. The finalizer then reported it as an unobserved task exception. That is routine rather than rare. The launch gate probes IsOwned while a viewer it has just started is still binding, and on Windows a connect to a port nothing is listening on is not refused at once, so the half second wait expires. Running ViewerLaunchTests.AcceptAllOverALongQueue printed two of them, and any test process that launches the viewer gets the same, fatally in a host that treats unobserved task exceptions as fatal. Both sites now connect through one helper, which observes the abandoned task with a continuation. The timeouts, and what Found records, are unchanged. AConnectGivenUpOnIsObserved gives up on five connects with a zero wait, which abandons them whatever the platform does with a closed port, then collects and asserts nothing was reported. It fails on the old code on net10 and net48.
This was referenced Sep 22, 2026
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This was referenced Sep 23, 2026
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ViewerClient.IsOwned and the synchronous TrySend wait on ConnectAsync for a bounded time, inside a using. A connect given up on is still pending when the client is disposed, and faults once that tears it down - or, where the port refuses rather than hangs, when the refusal arrives - with nobody left to observe it. The finalizer then reported it as an unobserved task exception.
That is routine rather than rare. The launch gate probes IsOwned while a viewer it has just started is still binding, and on Windows a connect to a port nothing is listening on is not refused at once, so the half second wait expires. Running ViewerLaunchTests.AcceptAllOverALongQueue printed two of them, and any test process that launches the viewer gets the same, fatally in a host that treats unobserved task exceptions as fatal.
Both sites now connect through one helper, which observes the abandoned task with a continuation. The timeouts, and what Found records, are unchanged.
AConnectGivenUpOnIsObserved gives up on five connects with a zero wait, which abandons them whatever the platform does with a closed port, then collects and asserts nothing was reported. It fails on the old code on net10 and net48.