Opting for performance over broad multi-actor "debug-ability" from
sync-function-contexts when `debug_mode=True` is set;
IOW prefer no behind-the-scenes `greenlet` perf impact over being
able to use an actor-safe `breakpoint()` wherever as per,
https://greenback.readthedocs.io/en/latest/principle.html#performance
Adjust the breakpoint restore ex script to match.
If the underlying example script fails (say due to a console output
pattern-mismatch, `AssertionError`) the `pexpect` managed subproc with
a `debug_mode=True` crash-handling-REPL engaged will ofc *not terminate*
due to any SIGINT sent by the test harnesss (since we shield from it as
part of normal sub-actor debugger operation). So instead always send
a 'continue' cmd to the active `PdbREPL`'s stdin so it deactivates and
allows the py-script-process to raise and terminate, unblocking the
`pexpect.spawn`'s internal subproc joiner (which would otherwise hang
without manual intervention, blocking downstream tests..).
Also, use the new `PexpectSpawner` type alias after actually importing
future annots.. XD
Such that we can more easily annotate any consumer test's of our
`.tests.devx.conftest.spawn()` fixture which delivers a closure which, when
called in a test fn body, transitively sub-invokes:
`pytest.Pytester.spawn()` -> `pexpect.spawn()`
IMO Expecting `Callable[[str], pexpect.pty_spawn.spawn]]` to be used all
over is a bit too.. verbose?
Dropping the `_maybe_open_repl_fixture()` approach and instead using
a `DebugStatus._fixture_stack = ExitStack()` which provides for much
simpler support around both sync and async pausing APIs thanks to only
invoking `repl_fixture.__exit__()` on actual `PdbREPL` interaction being
complete!
Deats,
- all `repl_fixture` detection logic still happens in one place (the new
method) but we aren't limited to closing it via an immediate post REPL
`.__exit__()` call which instead is triggered by,
- `DebugStatus.release()` which now calls `._fixture_stack.close()` and
thus only invokes `repl_fixture.__exit__()` when user REPL-ing is
**actually complete** an arbitrary amount of debugging time later.
- include the notes for `@acm` support above the new method, though not
sure if they're as relevant any more?
Benefits,
- we can drop the previously added indent levels from
`_enter_repl_sync()` and `_post_mortem()`.
- now we automatically have support for the `.pause_from_sync()` API
since `_enter_repl_sync()` doesn't close the prior
`_maybe_open_repl_fixture()` immediately when `debug_func=None`; the
user's `__exit__()` is only ever called once `.release()` is.
Other,
- add big 'CASE' comments around the various blocks in
`.pause_from_sync()`, i was having trouble figuring out which i was
using from a `breakpoint()` in a dependent app..
Oddly my env was borked bc this (apparently missed by `uv`?) sub-dep
wasn't installed and then `stackscope` was silently failing import and
caused the shield-pause test to also fail (since it couldn't match the
expected `log.devx()` on console). The import failure is not very
explanatory due to the `log.warning()`; change it to `.error()` level.
Also, explicitly import `_sync_pause_from_builtin` in
`examples/debugging/restore_builtin_breakpoint.py` to ensure the ref is
exported properly from `.devx.debug` (which it wasn't during dev of the
prior commit Bp).
Which cleans out the pkg-mod to just the expected exports with (its
longstanding todo comment list) and thus a separation-of-concerns
and smaller mod-file sizes via the following new sub-mods:
- `._trace` for the `.pause()`/`breakpoint()`/`pdb.set_trace()`-style
APIs including all sync-caller variants.
- `._post_mortem` to contain our async `.post_mortem()` and all other
public crash handling APIs for use from sync callers.
- `._sync` for the high-level syncing helper-routines used throughout the
runtime to avoid multi-proc TTY use collisions.
And also,
- remove `hide_runtime_frames()` since moved to `.devx._frame_stack`.
As per the outstanding TODO just above the redic `setattr()` loop in
`Actor._from_parent()`!!
Instead of all that risk-ay monkeying, add detailed comment-sections
around each explicit assignment of each `SpawnSpec` field, including
those that were already being explicitly set.
Those and other deats,
- ONLY enable the `.devx.debug._tty_lock` module from `Actor.__init__()`
in the root actor.
- add a new `get_mod_nsps2fps()` to replace the loop in init and assign
the initial `.enable_modules: dict[str, str]` from it.
- do `self.enable_modules.update(spawnspec.enable_modules)` instead of
an overwrite and assert the table is by default empty in all
subs.
From what was originall the `.devx._debug` monolith module, since that
file was way out of ctl in terms of LoC!
New modules so far include,
- ._repl: our `pdb[p]` ext type/lowlevel-APIs and `mk_pdb()` factory.
- ._sigint: just our REPL-interaction shield-handler.
- ._tty_lock: containing all the root-actor TTY mutex machinery
including the `Lock`/`DebugStatus` primitives/APIs as well as the
inter-tree IPC context eps:
* the server-side `lock_stdio_for_peer()` which pairs with the,
* client-(subactor)-side `request_root_stdio_lock()` via the,
* pld-msg-spec of `LockStatus/LockRelease`.
AND the `any_connected_locker_child()` predicate.
Factoring the (basically duplicate) content from both use spots into
a common `@cm` which delivers a `bool` signalling whether the REPL
should be engaged. Fixes a lingering bug with `nullcontext()` calling
btw..
By supporting a new optional param to `open_crash_handler()`,
`raise_on_exit: bool|Sequence[Type[BaseException]] = True` which
determines whether, after the REPL interaction completes, the handled
exception is raised upward. This is **very** handy for writing bits of
"debug-able but resilient code" as is the case in (many) dependent
projects/apps.
Impl,
- `raise_on_exit` can be a `bool` or (set) sequence of types which will
always be raised.
- also add a `BoxedMaybeException.raise_on_exit` equiv which (for now)
we check matches (in case down the road we want to offer dynamic ctls).
- rename both crash-handler cm's `tb_hide` -> `hide_tb`.
It turns out to be fairly useful to allow hooking into a given actor's
entry-and-exit around `.devx._debug._pause/._post_mortem()` calls which
engage the `pdbp.Pdb` REPL (really our `._debug.PdbREPL` but yeah).
Some very handy use cases include,
- swapping out-of-band (config) state that may otherwise halt the
user's app since the actor normally handles kb&mouse input, in thread,
which means that the handler will be blocked while the REPL is in use.
- (remotely) reporting actor-runtime state for monitoring purposes
around crashes or pauses in normal operation.
- allowing for crash-handling to be hard-disabled via
`._state._runtime_vars` say for when you never want a debugger to be
entered in a production instance where you're not-sure-if/don't-want
per-actor `debug_mode: bool` settings to always be unset, say bc
you're still debugging some edge cases that ow you'd normally want to
REPL up.
Impl details,
- add a new optional `._state._runtime_vars['repl_fixture']` field which
for now can be manually set; i saw no reason for a formal API yet
since we want to convert the `dict` to a struct anyway (first).
- augment both `.devx._debug._pause()/._post_mortem()` with a new
optional `repl_fixture: AbstractContextManager[bool]` kwarg which
when provided is `with repl_fixture()` opened around the lowlevel
REPL interaction calls; if the enter-result, an expected `bool`, is
`False` then the interaction is hard-bypassed.
* for the `._pause()` case the `@cm` is opened around the entire body
of the embedded `_enter_repl_sync()` closure (for now) though
ideally longer term this entire routine is factored to be a lot less
"nested" Bp
* in `_post_mortem()` the entire previous body is wrapped similarly
and also now excepts an optional `boxed_maybe_exc: BoxedMaybeException`
only passed in the `open_crash_handler()` caller case.
- when the new runtime-var is overridden, (only manually atm) it is used
instead but only whenever the above `repl_fixture` kwarg is left null.
- add a `BoxedMaybeException.pformat() = __repr__()` which when
a `.value: Exception` is set renders a more "objecty" repr of the exc.
Obviously tests for all this should be coming soon!
Tyler Goodlet