More or less by pedantically separating and managing root and subactor
request syncing events to always be managed by the locking IPC context
task-funcs:
- for the root's "child"-side, `lock_tty_for_child()` directly creates
and sets a new `Lock.req_handler_finished` inside a `finally:`
- for the sub's "parent"-side, `request_root_stdio_lock()` does the same
with a new `DebugStatus.req_finished` event and separates it from
the `.repl_release` event (which indicates a "c" or "q" from user and
thus exit of the REPL session) as well as sets a new `.req_task:
trio.Task` to explicitly distinguish from the app-user-task that
enters the REPL vs. the paired bg task used to request the global
root's stdio mutex alongside it.
- apply the `__pld_spec__` on "child"-side of the ctx using the new
`Portal.open_context(pld_spec)` parameter support; drops use of any
`ContextVar` malarky used prior for `PldRx` mgmt.
- removing `Lock.no_remote_has_tty` since it was a nebulous name and
from the prior "everything is in a `Lock`" design..
------ - ------
More rigorous impl to handle various edge cases in `._pause()`:
- rejig `_enter_repl_sync()` to wrap the `debug_func == None` case
inside maybe-internal-error handler blocks.
- better logic for recurrent vs. multi-task contention for REPL entry in
subactors, by guarding using `DebugStatus.req_task` and by now waiting
on the new `DebugStatus.req_finished` for the multi-task contention
case.
- even better internal error handling and reporting for when this code
is hacked on and possibly broken ;p
------ - ------
Updates to `.pause_from_sync()` support:
- add optional `actor`, `task` kwargs to `_set_trace()` to allow
compat with the new explicit `debug_func` calling in `._pause()` and
pass a `threading.Thread` for `task` in the `.to_thread()` usage case.
- add an `except` block that tries to show the frame on any internal
error.
------ - ------
Relatedly includes a buncha cleanups/simplifications somewhat in
prep for some coming refinements (around `DebugStatus`):
- use all the new attrs mentioned above as needed in the SIGINT shielder.
- wait on `Lock.req_handler_finished` in `maybe_wait_for_debugger()`.
- dropping a ton of masked legacy code left in during the recent reworks.
- better comments, like on the use of `Context._scope` for shielding on
the "child"-side to avoid the need to manage yet another cs.
- add/change-to lotsa `log.devx()` level emissions for those infos which
are handy while hacking on the debugger but not ideal/necessary to be
user visible.
- obvi add lotsa follow up todo notes!
9ab9726227