Attempting a rework of the post-cancellation "raising semantics" such
that subactors which are `ActorCancelled` as a result of a non-graceful
in-scope error, are acked via a re-raised
`ExceptionGroup[ActorCancelled*N, Exception]`
*outside the an-block*. Eventually, the idea is to have `ActorCancelled`
be relayed from each subactor in response to any
`Actor.cancel()/Portal.cancel_actor()` request much like
`Context.cancel()/ContextCancelled`.
This is a WIP bc it does break a few tests and requires related
`_spawn`-mod-machinery changes to match some of which I'm not yet sure
are required; need to dig into to the details of the currently failing
suites first.
`._supervise` patch deats,
- add `ActorNursery.maybe_error` which delivers the maybe-EG or
`._scope_error` depending on `.errors` (now `._errors`, a mapping from
`Aid`-keys) has entries seet for subs.
- raise ^ if non-null in a new outer-`finally` in
`_open_and_supervise_one_cancels_all_nursery()`; an "outer" block is
added to ensure all sub-actor-excs are emited/captured as part of
`ActorNursery.cancel()` being called (as prior) as well as the
`da_nursery` being explicitly cancelled alongside it (to unblock the
tn-block, but still not sure why this is necessary yet?..).
- (now masked) tried injecting actorcs from `.cancel()` loop, but (again
per more explanation in section below) seems to be suffering a race
issue with RAE relay?
- left in buncha notes obvi for all this..
`._spawn` patch deats,
- as above, expect `errors: dict` to map from `Aid`-keys.
- pass `errors: dict` into `soft_kill()` since it seemed like we'd want
to (for now) inject `ActoreCancelled` in some cases (but now i'm not
sure XD).
- tried out a couple spots (which are now masked) to inject
`ActorCancelled` after calling `Portal.cancel()` in various
subactor-supervision routines whenev an RAE is not set..
- oddly seems to be overwriting actual errors (likely due to racing
with RAE receive and/or actorc-request timeout?) despite the guard
logic..which clearly doesn't resolve the issue..
- buncha `tn`-style renaming.
b3d348ee6a