The final issue was making sure we do the same thing on ctl-c/SIGINT
from the user. That is, if there's already a bg-thread in REPL, we
`log.pdb()` about SIGINT shielding and re-draw the prompt; the same UX
as normal actor-runtime-task behaviour.
Reasons this wasn't workin.. and the fix:
- `.pause_from_sync()` was overriding the local `repl` var with `None`
delivered by (transitive) calls to `_pause(debug_func=None)`.. so
remove all that and only assign it OAOO prior to thread-type case
branching.
- always call `DebugStatus.shield_sigint()` as needed from all requesting
threads/tasks:
- in `_pause_from_bg_root_thread()` BEFORE calling `._pause()` AND BEFORE
yielding back to the bg-thread via `.started(out)` to ensure we're
definitely overriding the handler in the `trio`-main-thread task
before unblocking the requesting bg-thread.
- from any requesting bg-thread in the root actor such that both its
main-`trio`-thread scheduled task (as per above bullet) AND it are
SIGINT shielded.
- always call `.shield_sigint()` BEFORE any `greenback._await()` case
don't entirely grok why yet, but it works)?
- for `greenback._await()` case always set `bg_task` to the current one..
- tweaks to the `SIGINT` handler, now renamed `sigint_shield()` so as
not to name-collide with the methods when editor-searching:
- always try to `repr()` the REPL thread/task "owner" as well as the
active `PdbREPL` instance.
- add `.devx()` notes around the prompt flushing deats and comments
for any root-actor-bg-thread edge cases.
Related/supporting refinements:
- add `get_lock()`/`get_debug_req()` factory funcs since the plan is to
eventually implement both as `@singleton` instances per actor.
- fix `acquire_debug_lock()`'s call-sig-bug for scheduling
`request_root_stdio_lock()`..
- in `._pause()` only call `mk_pdb()` when `debug_func != None`.
- add some todo/warning notes around the `cls.repl = None` in
`DebugStatus.release()`
`test_pause_from_sync()` tweaks:
- don't use a `attach_patts.copy()`, since we always `break` on match.
- do `pytest.fail()` on that ^ loop's fallthrough..
- pass `do_ctlc(child, patt=attach_key)` such that we always match the
the current thread's name with the ctl-c triggered `.pdb()` emission.
- oh yeah, return the last `before: str` from `do_ctlc()`.
- in the script, flip `abandon_on_cancel=True` since when `False` it
seems to cause `trio.run()` to hang on exit from the last bg-thread
case?!?
5cdd012417