tractor/newsfragments/264.bug.rst

Fix ``Portal.run_in_actor()`` returns ``None`` result.

``None`` was being used as the cached result flag and obviously breaks
on a ``None`` returned from the remote target task. This would cause an
infinite hang if user code ever called ``Portal.result()`` *before* the
nursery exit. The simple fix is to use the *return message* as the
initial "no-result-received-yet" flag value and, once received, the
return value is read from the message to avoid the cache logic error.
Add nooz 2021-11-29 00:16:47 +00:00			Fix ``Portal.run_in_actor()`` returns ``None`` result.

			``None`` was being used as the cached result flag and obviously breaks
			on a ``None`` returned from the remote target task. This would cause an
			infinite hang if user code ever called ``Portal.result()`` before the
Cache the return message instead of the value Thanks to @richardsheridan for pointing out the limitations of using any kind of value as the result-cached-flag and how it might cause problems for anyone returning pickled blob-data. This changes the `Portal` internal result value tracking to stash the full message from which the value can be retrieved by any `Portal.result()` caller. The internal change is that `Portal._return_once()` now returns a tuple of the message and its value. 2021-11-29 12:27:14 +00:00			`nursery exit. The simple fix is to use the return message as the`
			`initial "no-result-received-yet" flag value and, once received, the`
			`return value is read from the message to avoid the cache logic error.`