Avoid "task never called `.started()`" runtime erros when cancelling

eg_backup
Tyler Goodlet 2022-10-14 17:43:45 -04:00
parent c47575997a
commit f2641c8964
1 changed files with 19 additions and 11 deletions

View File

@ -391,7 +391,7 @@ async def wait_for_parent_stdin_hijack(
finally: finally:
Lock.local_task_in_debug = None Lock.local_task_in_debug = None
log.debug(f'Exiting debugger from child') log.debug('Exiting debugger from child')
def mk_mpdb() -> tuple[MultiActorPdb, Callable]: def mk_mpdb() -> tuple[MultiActorPdb, Callable]:
@ -424,9 +424,8 @@ async def _breakpoint(
''' '''
__tracebackhide__ = True __tracebackhide__ = True
pdb, undo_sigint = mk_mpdb()
actor = tractor.current_actor() actor = tractor.current_actor()
pdb, undo_sigint = mk_mpdb()
task_name = trio.lowlevel.current_task().name task_name = trio.lowlevel.current_task().name
# TODO: is it possible to debug a trio.Cancelled except block? # TODO: is it possible to debug a trio.Cancelled except block?
@ -450,7 +449,10 @@ async def _breakpoint(
# Recurrence entry case: this task already has the lock and # Recurrence entry case: this task already has the lock and
# is likely recurrently entering a breakpoint # is likely recurrently entering a breakpoint
if Lock.local_task_in_debug == task_name: if Lock.local_task_in_debug == task_name:
# noop on recurrent entry case # noop on recurrent entry case but we want to trigger
# a checkpoint to allow other actors error-propagate and
# potetially avoid infinite re-entries in some subactor.
await trio.lowlevel.checkpoint()
return return
# if **this** actor is already in debug mode block here # if **this** actor is already in debug mode block here
@ -469,10 +471,13 @@ async def _breakpoint(
# root nursery so that the debugger can continue to run without # root nursery so that the debugger can continue to run without
# being restricted by the scope of a new task nursery. # being restricted by the scope of a new task nursery.
# NOTE: if we want to debug a trio.Cancelled triggered exception # TODO: if we want to debug a trio.Cancelled triggered exception
# we have to figure out how to avoid having the service nursery # we have to figure out how to avoid having the service nursery
# cancel on this task start? I *think* this works below? # cancel on this task start? I *think* this works below:
# ```python
# actor._service_n.cancel_scope.shield = shield # actor._service_n.cancel_scope.shield = shield
# ```
# but not entirely sure if that's a sane way to implement it?
try: try:
with trio.CancelScope(shield=True): with trio.CancelScope(shield=True):
await actor._service_n.start( await actor._service_n.start(
@ -481,6 +486,13 @@ async def _breakpoint(
) )
except RuntimeError: except RuntimeError:
Lock.release() Lock.release()
if actor._cancel_called:
# service nursery won't be usable and we
# don't want to lock up the root either way since
# we're in (the midst of) cancellation.
return
raise raise
elif is_root_process(): elif is_root_process():
@ -531,10 +543,6 @@ async def _breakpoint(
# # last_f = frame.f_back # # last_f = frame.f_back
# # last_f.f_globals['__tracebackhide__'] = True # # last_f.f_globals['__tracebackhide__'] = True
# # signal.signal = pdbpp.hideframe(signal.signal) # # signal.signal = pdbpp.hideframe(signal.signal)
# signal.signal(
# signal.SIGINT,
# orig_handler
# )
def shield_sigint( def shield_sigint(