Rename `._error` -> `._remote_ctx_error`

The case exists where there is multiple tasks consuming from an open
2-way stream created via `Context.open_stream()` where a sibling task is
pulling from the stream while some other task also calls `.result()`.
Previously the `.result()` call would consume (drain) stream messages
directly from the underlying mem chan which would mean any sibling task
would not receive those same messages. Instead, make `.result()` check
if a stream is open and instead consume (and discard) stream msgs using
a `BroadcastReceiver` (via `MsgStream.subscribe()`) such that all
interested tasks get copies of the same packets.

docs/README.rst

@@ -6,14 +6,8 @@
 ``tractor`` is a `structured concurrent`_, multi-processing_ runtime
 built on trio_.
 
-Fundamentally, ``tractor`` gives you parallelism via
+Fundamentally ``tractor`` gives you parallelism via ``trio``-"*actors*":
-``trio``-"*actors*": independent Python processes (aka
+our nurseries_ let you spawn new Python processes which each run a ``trio``
-non-shared-memory threads) which maintain structured
-concurrency (SC) *end-to-end* inside a *supervision tree*.
-
-Cross-process (and thus cross-host) SC is accomplished through the
-combined use of our "actor nurseries_" and an "SC-transitive IPC
-protocol" constructed on top of multiple Pythons each running a ``trio``
 scheduled runtime - a call to ``trio.run()``.
 
 We believe the system adheres to the `3 axioms`_ of an "`actor model`_"
@@ -29,8 +23,7 @@ Features
 - **It's just** a ``trio`` API
 - *Infinitely nesteable* process trees
 - Builtin IPC streaming APIs with task fan-out broadcasting
-- A "native" multi-core debugger REPL using `pdbp`_ (a fork & fix of
+- A (first ever?) "native" multi-core debugger UX for Python using `pdb++`_
-  `pdb++`_ thanks to @mdmintz!)
 - Support for a swappable, OS specific, process spawning layer
 - A modular transport stack, allowing for custom serialization (eg. with
   `msgspec`_), communications protocols, and environment specific IPC
@@ -125,7 +118,7 @@ Zombie safe: self-destruct a process tree
             f"running in pid {os.getpid()}"
         )
 
-        await trio.sleep_forever()
+       await trio.sleep_forever()
 
 
     async def main():
@@ -156,7 +149,7 @@ it **is a bug**.
 
 "Native" multi-process debugging
 --------------------------------
-Using the magic of `pdbp`_ and our internal IPC, we've
+Using the magic of `pdb++`_ and our internal IPC, we've
 been able to create a native feeling debugging experience for
 any (sub-)process in your ``tractor`` tree.
 
@@ -604,7 +597,6 @@ channel`_!
 .. _adherance to: https://www.youtube.com/watch?v=7erJ1DV_Tlo&t=1821s
 .. _trio gitter channel: https://gitter.im/python-trio/general
 .. _matrix channel: https://matrix.to/#/!tractor:matrix.org
-.. _pdbp: https://github.com/mdmintz/pdbp
 .. _pdb++: https://github.com/pdbpp/pdbpp
 .. _guest mode: https://trio.readthedocs.io/en/stable/reference-lowlevel.html?highlight=guest%20mode#using-guest-mode-to-run-trio-on-top-of-other-event-loops
 .. _messages: https://en.wikipedia.org/wiki/Message_passing

examples/debugging/restore_builtin_breakpoint.py

@@ -1,24 +0,0 @@
-import os
-import sys
-
-import trio
-import tractor
-
-
-async def main() -> None:
-    async with tractor.open_nursery(debug_mode=True) as an:
-
-        assert os.environ['PYTHONBREAKPOINT'] == 'tractor._debug._set_trace'
-
-        # TODO: an assert that verifies the hook has indeed been, hooked
-        # XD
-        assert sys.breakpointhook is not tractor._debug._set_trace
-
-        breakpoint()
-
-    # TODO: an assert that verifies the hook is unhooked..
-    assert sys.breakpointhook
-    breakpoint()
-
-if __name__ == '__main__':
-    trio.run(main)

nooz/356.trivial.rst

@@ -1,7 +0,0 @@
-Drop `trio.Process.aclose()` usage, copy into our spawning code.
-
-The details are laid out in https://github.com/goodboy/tractor/issues/330.
-`trio` changed is process running quite some time ago, this just copies
-out the small bit we needed (from the old `.aclose()`) for hard kills
-where a soft runtime cancel request fails and our "zombie killer"
-implementation kicks in.

nooz/358.feature.rst

@@ -1,15 +0,0 @@
-Switch to using the fork & fix of `pdb++`, `pdbp`:
-https://github.com/mdmintz/pdbp
-
-Allows us to sidestep a variety of issues that aren't being maintained
-in the upstream project thanks to the hard work of @mdmintz!
-
-We also include some default settings adjustments as per recent
-development on the fork:
-
-- sticky mode is still turned on by default but now activates when
-  a using the `ll` repl command.
-- turn off line truncation by default to avoid inter-line gaps when
-  resizing the terimnal during use.
-- when using the backtrace cmd either by `w` or `bt`, the config
-  automatically switches to non-sticky mode.

requirements-test.txt

@@ -1,7 +1,7 @@
 pytest
 pytest-trio
 pytest-timeout
-pdbp
+pdbpp
 mypy
 trio_typing
 pexpect

setup.py

@@ -26,12 +26,12 @@ with open('docs/README.rst', encoding='utf-8') as f:
 setup(
     name="tractor",
     version='0.1.0a6dev0',  # alpha zone
-    description='structured concurrrent `trio`-"actors"',
+    description='structured concurrrent "actors"',
     long_description=readme,
     license='AGPLv3',
     author='Tyler Goodlet',
     maintainer='Tyler Goodlet',
-    maintainer_email='goodboy_foss@protonmail.com',
+    maintainer_email='jgbt@protonmail.com',
     url='https://github.com/goodboy/tractor',
     platforms=['linux', 'windows'],
     packages=[
@@ -52,14 +52,16 @@ setup(
         # tooling
         'tricycle',
         'trio_typing',
+
+        # tooling
         'colorlog',
         'wrapt',
 
-        # IPC serialization
+        # serialization
         'msgspec',
 
         # debug mode REPL
-        'pdbp',
+        'pdbpp',
 
         # pip ref docs on these specs:
         # https://pip.pypa.io/en/stable/reference/requirement-specifiers/#examples
@@ -71,9 +73,10 @@ setup(
         # https://github.com/pdbpp/fancycompleter/issues/37
         'pyreadline3 ; platform_system == "Windows"',
 
+
     ],
     tests_require=['pytest'],
-    python_requires=">=3.10",
+    python_requires=">=3.9",
     keywords=[
         'trio',
         'async',

tests/test_debugger.py

@@ -95,7 +95,7 @@ def spawn(
     return _spawn
 
 
-PROMPT = r"\(Pdb\+\)"
+PROMPT = r"\(Pdb\+\+\)"
 
 
 def expect(
@@ -151,6 +151,18 @@ def ctlc(
 
     use_ctlc = request.param
 
+    if (
+        sys.version_info <= (3, 10)
+        and use_ctlc
+    ):
+        # on 3.9 it seems the REPL UX
+        # is highly unreliable and frankly annoying
+        # to test for. It does work from manual testing
+        # but i just don't think it's wroth it to try
+        # and get this working especially since we want to
+        # be 3.10+ mega-asap.
+        pytest.skip('Py3.9 and `pdbpp` son no bueno..')
+
     node = request.node
     markers = node.own_markers
     for mark in markers:
@@ -181,15 +193,13 @@ def ctlc(
     ids=lambda item: f'{item[0]} -> {item[1]}',
 )
 def test_root_actor_error(spawn, user_in_out):
-    '''
+    """Demonstrate crash handler entering pdbpp from basic error in root actor.
-    Demonstrate crash handler entering pdb from basic error in root actor.
+    """
-
-    '''
     user_input, expect_err_str = user_in_out
 
     child = spawn('root_actor_error')
 
-    # scan for the prompt
+    # scan for the pdbpp prompt
     expect(child, PROMPT)
 
     before = str(child.before.decode())
@@ -220,8 +230,8 @@ def test_root_actor_bp(spawn, user_in_out):
     user_input, expect_err_str = user_in_out
     child = spawn('root_actor_breakpoint')
 
-    # scan for the prompt
+    # scan for the pdbpp prompt
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     assert 'Error' not in str(child.before)
 
@@ -262,7 +272,7 @@ def do_ctlc(
         if expect_prompt:
             before = str(child.before.decode())
             time.sleep(delay)
-            child.expect(PROMPT)
+            child.expect(r"\(Pdb\+\+\)")
             time.sleep(delay)
 
             if patt:
@@ -281,7 +291,7 @@ def test_root_actor_bp_forever(
     # entries
     for _ in range(10):
 
-        child.expect(PROMPT)
+        child.expect(r"\(Pdb\+\+\)")
 
         if ctlc:
             do_ctlc(child)
@@ -291,7 +301,7 @@ def test_root_actor_bp_forever(
     # do one continue which should trigger a
     # new task to lock the tty
     child.sendline('continue')
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     # seems that if we hit ctrl-c too fast the
     # sigint guard machinery might not kick in..
@@ -302,10 +312,10 @@ def test_root_actor_bp_forever(
 
     # XXX: this previously caused a bug!
     child.sendline('n')
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     child.sendline('n')
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     # quit out of the loop
     child.sendline('q')
@@ -328,8 +338,8 @@ def test_subactor_error(
     '''
     child = spawn('subactor_error')
 
-    # scan for the prompt
+    # scan for the pdbpp prompt
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     before = str(child.before.decode())
     assert "Attaching to pdb in crashed actor: ('name_error'" in before
@@ -349,7 +359,7 @@ def test_subactor_error(
         # creating actor
         child.sendline('continue')
 
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
     before = str(child.before.decode())
 
     # root actor gets debugger engaged
@@ -376,8 +386,8 @@ def test_subactor_breakpoint(
 
     child = spawn('subactor_breakpoint')
 
-    # scan for the prompt
+    # scan for the pdbpp prompt
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     before = str(child.before.decode())
     assert "Attaching pdb to actor: ('breakpoint_forever'" in before
@@ -386,7 +396,7 @@ def test_subactor_breakpoint(
     # entries
     for _ in range(10):
         child.sendline('next')
-        child.expect(PROMPT)
+        child.expect(r"\(Pdb\+\+\)")
 
         if ctlc:
             do_ctlc(child)
@@ -394,7 +404,7 @@ def test_subactor_breakpoint(
     # now run some "continues" to show re-entries
     for _ in range(5):
         child.sendline('continue')
-        child.expect(PROMPT)
+        child.expect(r"\(Pdb\+\+\)")
         before = str(child.before.decode())
         assert "Attaching pdb to actor: ('breakpoint_forever'" in before
 
@@ -405,7 +415,7 @@ def test_subactor_breakpoint(
     child.sendline('q')
 
     # child process should exit but parent will capture pdb.BdbQuit
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     before = str(child.before.decode())
     assert "RemoteActorError: ('breakpoint_forever'" in before
@@ -437,8 +447,8 @@ def test_multi_subactors(
     '''
     child = spawn(r'multi_subactors')
 
-    # scan for the prompt
+    # scan for the pdbpp prompt
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     before = str(child.before.decode())
     assert "Attaching pdb to actor: ('breakpoint_forever'" in before
@@ -450,7 +460,7 @@ def test_multi_subactors(
     # entries
     for _ in range(10):
         child.sendline('next')
-        child.expect(PROMPT)
+        child.expect(r"\(Pdb\+\+\)")
 
         if ctlc:
             do_ctlc(child)
@@ -459,7 +469,7 @@ def test_multi_subactors(
     child.sendline('c')
 
     # first name_error failure
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
     before = str(child.before.decode())
     assert "Attaching to pdb in crashed actor: ('name_error'" in before
     assert "NameError" in before
@@ -471,7 +481,7 @@ def test_multi_subactors(
     child.sendline('c')
 
     # 2nd name_error failure
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     # TODO: will we ever get the race where this crash will show up?
     # blocklist strat now prevents this crash
@@ -485,7 +495,7 @@ def test_multi_subactors(
 
     # breakpoint loop should re-engage
     child.sendline('c')
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
     before = str(child.before.decode())
     assert "Attaching pdb to actor: ('breakpoint_forever'" in before
 
@@ -501,7 +511,7 @@ def test_multi_subactors(
     ):
         child.sendline('c')
         time.sleep(0.1)
-        child.expect(PROMPT)
+        child.expect(r"\(Pdb\+\+\)")
         before = str(child.before.decode())
 
         if ctlc:
@@ -520,11 +530,11 @@ def test_multi_subactors(
     # now run some "continues" to show re-entries
     for _ in range(5):
         child.sendline('c')
-        child.expect(PROMPT)
+        child.expect(r"\(Pdb\+\+\)")
 
     # quit the loop and expect parent to attach
     child.sendline('q')
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
     before = str(child.before.decode())
 
     assert_before(child, [
@@ -568,7 +578,7 @@ def test_multi_daemon_subactors(
     '''
     child = spawn('multi_daemon_subactors')
 
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     # there can be a race for which subactor will acquire
     # the root's tty lock first so anticipate either crash
@@ -598,7 +608,7 @@ def test_multi_daemon_subactors(
     # second entry by `bp_forever`.
 
     child.sendline('c')
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
     assert_before(child, [next_msg])
 
     # XXX: hooray the root clobbering the child here was fixed!
@@ -620,7 +630,7 @@ def test_multi_daemon_subactors(
 
     # expect another breakpoint actor entry
     child.sendline('c')
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     try:
         assert_before(child, [bp_forever_msg])
@@ -636,7 +646,7 @@ def test_multi_daemon_subactors(
         # after 1 or more further bp actor entries.
 
         child.sendline('c')
-        child.expect(PROMPT)
+        child.expect(r"\(Pdb\+\+\)")
         assert_before(child, [name_error_msg])
 
     # wait for final error in root
@@ -644,7 +654,7 @@ def test_multi_daemon_subactors(
     while True:
         try:
             child.sendline('c')
-            child.expect(PROMPT)
+            child.expect(r"\(Pdb\+\+\)")
             assert_before(
                 child,
                 [bp_forever_msg]
@@ -677,8 +687,8 @@ def test_multi_subactors_root_errors(
     '''
     child = spawn('multi_subactor_root_errors')
 
-    # scan for the prompt
+    # scan for the pdbpp prompt
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     # at most one subactor should attach before the root is cancelled
     before = str(child.before.decode())
@@ -693,7 +703,7 @@ def test_multi_subactors_root_errors(
 
     # due to block list strat from #337, this will no longer
     # propagate before the root errors and cancels the spawner sub-tree.
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     # only if the blocking condition doesn't kick in fast enough
     before = str(child.before.decode())
@@ -708,7 +718,7 @@ def test_multi_subactors_root_errors(
             do_ctlc(child)
 
         child.sendline('c')
-        child.expect(PROMPT)
+        child.expect(r"\(Pdb\+\+\)")
 
     # check if the spawner crashed or was blocked from debug
     # and if this intermediary attached check the boxed error
@@ -725,7 +735,7 @@ def test_multi_subactors_root_errors(
             do_ctlc(child)
 
         child.sendline('c')
-        child.expect(PROMPT)
+        child.expect(r"\(Pdb\+\+\)")
 
     # expect a root actor crash
     assert_before(child, [
@@ -774,7 +784,7 @@ def test_multi_nested_subactors_error_through_nurseries(
 
     for send_char in itertools.cycle(['c', 'q']):
         try:
-            child.expect(PROMPT)
+            child.expect(r"\(Pdb\+\+\)")
             child.sendline(send_char)
             time.sleep(0.01)
 
@@ -816,7 +826,7 @@ def test_root_nursery_cancels_before_child_releases_tty_lock(
 
     child = spawn('root_cancelled_but_child_is_in_tty_lock')
 
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     before = str(child.before.decode())
     assert "NameError: name 'doggypants' is not defined" in before
@@ -831,7 +841,7 @@ def test_root_nursery_cancels_before_child_releases_tty_lock(
     for i in range(4):
         time.sleep(0.5)
         try:
-            child.expect(PROMPT)
+            child.expect(r"\(Pdb\+\+\)")
 
         except (
             EOF,
@@ -888,7 +898,7 @@ def test_root_cancels_child_context_during_startup(
     '''
     child = spawn('fast_error_in_root_after_spawn')
 
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     before = str(child.before.decode())
     assert "AssertionError" in before
@@ -905,7 +915,7 @@ def test_different_debug_mode_per_actor(
     ctlc: bool,
 ):
     child = spawn('per_actor_debug')
-    child.expect(PROMPT)
+    child.expect(r"\(Pdb\+\+\)")
 
     # only one actor should enter the debugger
     before = str(child.before.decode())

tractor/__init__.py

@@ -44,10 +44,7 @@ from ._exceptions import (
     ModuleNotExposed,
     ContextCancelled,
 )
-from ._debug import (
+from ._debug import breakpoint, post_mortem
-    breakpoint,
-    post_mortem,
-)
 from . import msg
 from ._root import (
     run_daemon,

tractor/_debug.py

@@ -37,7 +37,6 @@ from typing import (
 )
 from types import FrameType
 
-import pdbp
 import tractor
 import trio
 from trio_typing import TaskStatus
@@ -54,6 +53,17 @@ from ._exceptions import (
 )
 from ._ipc import Channel
 
+
+try:
+    # wtf: only exported when installed in dev mode?
+    import pdbpp
+except ImportError:
+    # pdbpp is installed in regular mode...it monkey patches stuff
+    import pdb
+    xpm = getattr(pdb, 'xpm', None)
+    assert xpm, "pdbpp is not installed?"  # type: ignore
+    pdbpp = pdb
+
 log = get_logger(__name__)
 
 
@@ -144,26 +154,22 @@ class Lock:
             cls.repl = None
 
 
-class TractorConfig(pdbp.DefaultConfig):
+class TractorConfig(pdbpp.DefaultConfig):
     '''
-    Custom ``pdbp`` goodness :surfer:
+    Custom ``pdbpp`` goodness.
 
     '''
-    use_pygments: bool = True
+    # use_pygments = True
-    sticky_by_default: bool = False
+    # sticky_by_default = True
-    enable_hidden_frames: bool = False
+    enable_hidden_frames = False
-
-    # much thanks @mdmintz for the hot tip!
-    # fixes line spacing issue when resizing terminal B)
-    truncate_long_lines: bool = False
 
 
-class MultiActorPdb(pdbp.Pdb):
+class MultiActorPdb(pdbpp.Pdb):
     '''
-    Add teardown hooks to the regular ``pdbp.Pdb``.
+    Add teardown hooks to the regular ``pdbpp.Pdb``.
 
     '''
-    # override the pdbp config with our coolio one
+    # override the pdbpp config with our coolio one
     DefaultConfig = TractorConfig
 
     # def preloop(self):
@@ -307,7 +313,7 @@ async def lock_tty_for_child(
 ) -> str:
     '''
     Lock the TTY in the root process of an actor tree in a new
-    inter-actor-context-task such that the ``pdbp`` debugger console
+    inter-actor-context-task such that the ``pdbpp`` debugger console
     can be mutex-allocated to the calling sub-actor for REPL control
     without interference by other processes / threads.
 
@@ -427,7 +433,7 @@ async def wait_for_parent_stdin_hijack(
 def mk_mpdb() -> tuple[MultiActorPdb, Callable]:
 
     pdb = MultiActorPdb()
-    # signal.signal = pdbp.hideframe(signal.signal)
+    # signal.signal = pdbpp.hideframe(signal.signal)
 
     Lock.shield_sigint()
 
@@ -577,7 +583,7 @@ async def _breakpoint(
     #     # frame = sys._getframe()
     #     # last_f = frame.f_back
     #     # last_f.f_globals['__tracebackhide__'] = True
-    #     # signal.signal = pdbp.hideframe(signal.signal)
+    #     # signal.signal = pdbpp.hideframe(signal.signal)
 
 
 def shield_sigint_handler(
@@ -737,13 +743,13 @@ def shield_sigint_handler(
         # https://github.com/goodboy/tractor/issues/130#issuecomment-663752040
         # https://github.com/prompt-toolkit/python-prompt-toolkit/blob/c2c6af8a0308f9e5d7c0e28cb8a02963fe0ce07a/prompt_toolkit/patch_stdout.py
 
-        # XXX LEGACY: lol, see ``pdbpp`` issue:
+        # XXX: lol, see ``pdbpp`` issue:
         # https://github.com/pdbpp/pdbpp/issues/496
 
 
 def _set_trace(
-    actor: tractor.Actor | None = None,
+    actor: Optional[tractor.Actor] = None,
-    pdb: MultiActorPdb | None = None,
+    pdb: Optional[MultiActorPdb] = None,
 ):
     __tracebackhide__ = True
     actor = actor or tractor.current_actor()
@@ -753,11 +759,7 @@ def _set_trace(
     if frame:
         frame = frame.f_back  # type: ignore
 
-    if (
+    if frame and pdb and actor is not None:
-        frame
-        and pdb
-        and actor is not None
-    ):
         log.pdb(f"\nAttaching pdb to actor: {actor.uid}\n")
         # no f!#$&* idea, but when we're in async land
         # we need 2x frames up?
@@ -766,8 +768,7 @@ def _set_trace(
     else:
         pdb, undo_sigint = mk_mpdb()
 
-        # we entered the global ``breakpoint()`` built-in from sync
+        # we entered the global ``breakpoint()`` built-in from sync code?
-        # code?
         Lock.local_task_in_debug = 'sync'
 
     pdb.set_trace(frame=frame)
@@ -797,7 +798,7 @@ def _post_mortem(
     # https://github.com/pdbpp/pdbpp/issues/480
     # TODO: help with a 3.10+ major release if/when it arrives.
 
-    pdbp.xpm(Pdb=lambda: pdb)
+    pdbpp.xpm(Pdb=lambda: pdb)
 
 
 post_mortem = partial(

tractor/_root.py

@@ -22,9 +22,8 @@ from contextlib import asynccontextmanager
 from functools import partial
 import importlib
 import logging
-import signal
-import sys
 import os
+import signal
 import typing
 import warnings
 
@@ -85,10 +84,8 @@ async def open_root_actor(
 
     '''
     # Override the global debugger hook to make it play nice with
-    # ``trio``, see much discussion in:
+    # ``trio``, see:
     # https://github.com/python-trio/trio/issues/1155#issuecomment-742964018
-    builtin_bp_handler = sys.breakpointhook
-    orig_bp_path: str | None = os.environ.get('PYTHONBREAKPOINT', None)
     os.environ['PYTHONBREAKPOINT'] = 'tractor._debug._set_trace'
 
     # attempt to retreive ``trio``'s sigint handler and stash it
@@ -256,16 +253,6 @@ async def open_root_actor(
                 logger.cancel("Shutting down root actor")
                 await actor.cancel()
     finally:
-        _state._current_actor = None
-
-        # restore breakpoint hook state
-        sys.breakpointhook = builtin_bp_handler
-        if orig_bp_path is not None:
-            os.environ['PYTHONBREAKPOINT'] = orig_bp_path
-        else:
-            # clear env back to having no entry
-            os.environ.pop('PYTHONBREAKPOINT')
-
         logger.runtime("Root actor terminated")
 
 
@@ -301,7 +288,7 @@ def run_daemon(
     async def _main():
 
         async with open_root_actor(
-            registry_addr=registry_addr,
+            arbiter_addr=registry_addr,
             name=name,
             start_method=start_method,
             debug_mode=debug_mode,

tractor/_runtime.py

@@ -199,8 +199,8 @@ async def _invoke(
             except BaseExceptionGroup:
                 # if a context error was set then likely
                 # thei multierror was raised due to that
-                if ctx._error is not None:
+                if ctx._remote_ctx_error is not None:
-                    raise ctx._error from None
+                    raise ctx._remote_ctx_error from None
 
                 raise
 

tractor/_spawn.py

@@ -23,12 +23,13 @@ import sys
 import platform
 from typing import (
     Any,
-    Awaitable,
     Literal,
+    Optional,
     Callable,
     TypeVar,
     TYPE_CHECKING,
 )
+from collections.abc import Awaitable
 
 from exceptiongroup import BaseExceptionGroup
 import trio
@@ -59,7 +60,7 @@ if TYPE_CHECKING:
 log = get_logger('tractor')
 
 # placeholder for an mp start context if so using that backend
-_ctx: mp.context.BaseContext | None = None
+_ctx: Optional[mp.context.BaseContext] = None
 SpawnMethodKey = Literal[
     'trio',  # supported on all platforms
     'mp_spawn',
@@ -85,7 +86,7 @@ else:
 def try_set_start_method(
     key: SpawnMethodKey
 
-) -> mp.context.BaseContext | None:
+) -> Optional[mp.context.BaseContext]:
     '''
     Attempt to set the method for process starting, aka the "actor
     spawning backend".
@@ -199,37 +200,16 @@ async def cancel_on_completion(
 async def do_hard_kill(
     proc: trio.Process,
     terminate_after: int = 3,
-
 ) -> None:
     # NOTE: this timeout used to do nothing since we were shielding
     # the ``.wait()`` inside ``new_proc()`` which will pretty much
     # never release until the process exits, now it acts as
     # a hard-kill time ultimatum.
-    log.debug(f"Terminating {proc}")
     with trio.move_on_after(terminate_after) as cs:
 
-        # NOTE: code below was copied verbatim from the now deprecated
+        # NOTE: This ``__aexit__()`` shields internally.
-        # (in 0.20.0) ``trio._subrocess.Process.aclose()``, orig doc
+        async with proc:  # calls ``trio.Process.aclose()``
-        # string:
+            log.debug(f"Terminating {proc}")
-        #
-        # Close any pipes we have to the process (both input and output)
-        # and wait for it to exit. If cancelled, kills the process and
-        # waits for it to finish exiting before propagating the
-        # cancellation.
-        with trio.CancelScope(shield=True):
-            if proc.stdin is not None:
-                await proc.stdin.aclose()
-            if proc.stdout is not None:
-                await proc.stdout.aclose()
-            if proc.stderr is not None:
-                await proc.stderr.aclose()
-        try:
-            await proc.wait()
-        finally:
-            if proc.returncode is None:
-                proc.kill()
-                with trio.CancelScope(shield=True):
-                    await proc.wait()
 
     if cs.cancelled_caught:
         # XXX: should pretty much never get here unless we have
@@ -375,11 +355,12 @@ async def trio_proc(
         spawn_cmd.append("--asyncio")
 
     cancelled_during_spawn: bool = False
-    proc: trio.Process | None = None
+    proc: Optional[trio.Process] = None
     try:
         try:
             # TODO: needs ``trio_typing`` patch?
-            proc = await trio.lowlevel.open_process(spawn_cmd)
+            proc = await trio.lowlevel.open_process(    # type: ignore
+                spawn_cmd)
 
             log.runtime(f"Started {proc}")
 
@@ -463,8 +444,8 @@ async def trio_proc(
             nursery.cancel_scope.cancel()
 
     finally:
-        # XXX NOTE XXX: The "hard" reap since no actor zombies are
+        # The "hard" reap since no actor zombies are allowed!
-        # allowed! Do this **after** cancellation/teardown to avoid
+        # XXX: do this **after** cancellation/tearfown to avoid
         # killing the process too early.
         if proc:
             log.cancel(f'Hard reap sequence starting for {subactor.uid}')

tractor/_streaming.py

@@ -27,7 +27,8 @@ from typing import (
     Optional,
     Callable,
     AsyncGenerator,
-    AsyncIterator
+    AsyncIterator,
+    TYPE_CHECKING,
 )
 
 import warnings
@@ -41,6 +42,10 @@ from .log import get_logger
 from .trionics import broadcast_receiver, BroadcastReceiver
 
 
+if TYPE_CHECKING:
+    from ._portal import Portal
+
+
 log = get_logger(__name__)
 
 
@@ -70,7 +75,7 @@ class MsgStream(trio.abc.Channel):
     '''
     def __init__(
         self,
-        ctx: 'Context',  # typing: ignore # noqa
+        ctx: Context,  # typing: ignore # noqa
         rx_chan: trio.MemoryReceiveChannel,
         _broadcaster: Optional[BroadcastReceiver] = None,
 
@@ -83,6 +88,9 @@ class MsgStream(trio.abc.Channel):
         self._eoc: bool = False
         self._closed: bool = False
 
+    def ctx(self) -> Context:
+        return self._ctx
+
     # delegate directly to underlying mem channel
     def receive_nowait(self):
         msg = self._rx_chan.receive_nowait()
@@ -278,7 +286,6 @@ class MsgStream(trio.abc.Channel):
     @asynccontextmanager
     async def subscribe(
         self,
-
     ) -> AsyncIterator[BroadcastReceiver]:
         '''
         Allocate and return a ``BroadcastReceiver`` which delegates
@@ -335,8 +342,8 @@ class MsgStream(trio.abc.Channel):
         Send a message over this stream to the far end.
 
         '''
-        if self._ctx._error:
+        if self._ctx._remote_ctx_error:
-            raise self._ctx._error  # from None
+            raise self._ctx._remote_ctx_error  # from None
 
         if self._closed:
             raise trio.ClosedResourceError('This stream was already closed')
@@ -375,9 +382,10 @@ class Context:
     _remote_func_type: Optional[str] = None
 
     # only set on the caller side
-    _portal: Optional['Portal'] = None    # type: ignore # noqa
+    _portal: Optional[Portal] = None    # type: ignore # noqa
+    _stream: Optional[MsgStream] = None
     _result: Optional[Any] = False
-    _error: Optional[BaseException] = None
+    _remote_ctx_error: Optional[BaseException] = None
 
     # status flags
     _cancel_called: bool = False
@@ -390,7 +398,7 @@ class Context:
     # only set on the callee side
     _scope_nursery: Optional[trio.Nursery] = None
 
-    _backpressure: bool = False
+    _backpressure: bool = True
 
     async def send_yield(self, data: Any) -> None:
 
@@ -435,21 +443,26 @@ class Context:
             # (currently) that other portal APIs (``Portal.run()``,
             # ``.run_in_actor()``) do their own error checking at the point
             # of the call and result processing.
-            log.error(
-                f'Remote context error for {self.chan.uid}:{self.cid}:\n'
-                f'{msg["error"]["tb_str"]}'
-            )
             error = unpack_error(msg, self.chan)
             if (
-                isinstance(error, ContextCancelled) and
+                isinstance(error, ContextCancelled)
-                self._cancel_called
             ):
-                # this is an expected cancel request response message
+                log.cancel(
-                # and we don't need to raise it in scope since it will
+                    f'Remote context error for {self.chan.uid}:{self.cid}:\n'
-                # potentially override a real error
+                    f'{msg["error"]["tb_str"]}'
-                return
+                )
+                if self._cancel_called:
+                    # this is an expected cancel request response message
+                    # and we don't need to raise it in scope since it will
+                    # potentially override a real error
+                    return
+            else:
+                log.error(
+                    f'Remote context error for {self.chan.uid}:{self.cid}:\n'
+                    f'{msg["error"]["tb_str"]}'
+                )
 
-            self._error = error
+            self._remote_ctx_error = error
 
             # TODO: tempted to **not** do this by-reraising in a
             # nursery and instead cancel a surrounding scope, detect
@@ -457,7 +470,7 @@ class Context:
             if self._scope_nursery:
 
                 async def raiser():
-                    raise self._error from None
+                    raise self._remote_ctx_error from None
 
                 # from trio.testing import wait_all_tasks_blocked
                 # await wait_all_tasks_blocked()
@@ -483,6 +496,7 @@ class Context:
         log.cancel(f'Cancelling {side} side of context to {self.chan.uid}')
 
         self._cancel_called = True
+        ipc_broken: bool = False
 
         if side == 'caller':
             if not self._portal:
@@ -500,7 +514,14 @@ class Context:
                 # NOTE: we're telling the far end actor to cancel a task
                 # corresponding to *this actor*. The far end local channel
                 # instance is passed to `Actor._cancel_task()` implicitly.
-                await self._portal.run_from_ns('self', '_cancel_task', cid=cid)
+                try:
+                    await self._portal.run_from_ns(
+                        'self',
+                        '_cancel_task',
+                        cid=cid,
+                    )
+                except trio.BrokenResourceError:
+                    ipc_broken = True
 
             if cs.cancelled_caught:
                 # XXX: there's no way to know if the remote task was indeed
@@ -516,7 +537,10 @@ class Context:
                         "Timed out on cancelling remote task "
                         f"{cid} for {self._portal.channel.uid}")
 
-        # callee side remote task
+            elif ipc_broken:
+                log.cancel(
+                    "Transport layer was broken before cancel request "
+                    f"{cid} for {self._portal.channel.uid}")
         else:
             self._cancel_msg = msg
 
@@ -604,6 +628,7 @@ class Context:
             ctx=self,
             rx_chan=ctx._recv_chan,
         ) as stream:
+            self._stream = stream
 
             if self._portal:
                 self._portal._streams.add(stream)
@@ -645,25 +670,22 @@ class Context:
 
             if not self._recv_chan._closed:  # type: ignore
 
-                # wait for a final context result consuming
+                def consume(
-                # and discarding any bi dir stream msgs still
+                    msg: dict,
-                # in transit from the far end.
-                while True:
 
-                    msg = await self._recv_chan.receive()
+                ) -> Optional[dict]:
                     try:
-                        self._result = msg['return']
+                        return msg['return']
-                        break
                     except KeyError as msgerr:
 
                         if 'yield' in msg:
                             # far end task is still streaming to us so discard
                             log.warning(f'Discarding stream delivered {msg}')
-                            continue
+                            return
 
                         elif 'stop' in msg:
                             log.debug('Remote stream terminated')
-                            continue
+                            return
 
                         # internal error should never get here
                         assert msg.get('cid'), (
@@ -673,6 +695,25 @@ class Context:
                             msg, self._portal.channel
                         ) from msgerr
 
+                # wait for a final context result consuming
+                # and discarding any bi dir stream msgs still
+                # in transit from the far end.
+                if self._stream:
+                    async with self._stream.subscribe() as bstream:
+                        async for msg in bstream:
+                            result = consume(msg)
+                            if result:
+                                self._result = result
+                                break
+
+                if not self._result:
+                    while True:
+                        msg = await self._recv_chan.receive()
+                        result = consume(msg)
+                        if result:
+                            self._result = result
+                            break
+
         return self._result
 
     async def started(

tractor/_supervise.py

@@ -302,7 +302,7 @@ async def _open_and_supervise_one_cancels_all_nursery(
 ) -> typing.AsyncGenerator[ActorNursery, None]:
 
     # TODO: yay or nay?
-    __tracebackhide__ = True
+    # __tracebackhide__ = True
 
     # the collection of errors retreived from spawned sub-actors
     errors: dict[tuple[str, str], BaseException] = {}