def test_outcomes_unwrap_raises_trio_error_over_qt_error():
"""Unwrapping an Outcomes prioritizes a Trio error over a Qt error."""
class LocalUniqueException(Exception):
pass
class AnotherUniqueException(Exception):
pass
this_outcome = qtrio.Outcomes(
qt=outcome.Error(AnotherUniqueException()),
trio=outcome.Error(LocalUniqueException()),
)
with pytest.raises(LocalUniqueException):
this_outcome.unwrap()
def callback():
# Protect against race-conditions
with condition:
# Notify the fuse thread/winfsp that the call has started
condition.notify()
# Check for cancellation in a thread-safe way
if cancelled:
queue.put_nowait(RuntimeError("Cancelled"))
return
# Wrapper for the asynchronous function
# Keyboard interrupt is enabled when using `trio_token.run_sync_soon`,
# So let's disable it as we're heading back to user code.
@trio.lowlevel.disable_ki_protection
async def unprotected_afn():
return await afn(*args)
# System task target
async def await_in_trio_thread_task():
queue.put_nowait(await outcome.acapture(unprotected_afn))
# Spawn system task
try:
trio.lowlevel.spawn_system_task(await_in_trio_thread_task, name=afn)
# System nursery is closed
except RuntimeError:
queue.put_nowait(outcome.Error(trio.RunFinishedError("system nursery is closed")))
async def _run(self) -> None:
"""
Context manager for this instance.
"""
# TODO nothing sets this ... yet
self._close = trio.Event()
async with trio.open_nursery() as n:
# fx is the FIFO, opened in read-write mode
fx = await n.start(self._reader)
self.main = n
self._is_running.set()
try:
await self._is_connected.wait()
if self._handlers:
async with trio.open_nursery() as nn:
for event in self._handlers.keys():
nn.start_soon(partial(self.rpc,action="handle", event=event))
self.do_register_aliases()
yield self
finally:
if fx is not None:
os.close(fx)
for k,v in self._replies.items():
if isinstance(v,trio.Event):
self._replies[k] = outcome.Error(EOFError())
v.set()
n.cancel_scope.cancel()
pass # end finally
pass # end nursery
async def __trio_thread_main(self):
# The non-context-manager equivalent of open_loop()
async with trio.open_nursery() as nursery:
asyncio.set_event_loop(self)
await self._main_loop_init(nursery)
self.__blocking_result_queue.put(True)
while not self._closed:
# This *blocks*
req = self.__blocking_job_queue.get()
if req is None:
self.stop()
break
async_fn, args = req
result = await outcome.acapture(async_fn, *args)
if type(result) == outcome.Error and type(
result.error) == trio.Cancelled:
res = RuntimeError("Main loop cancelled")
res.__cause__ = result.error.__cause__
result = outcome.Error(res)
self.__blocking_result_queue.put(result)
with trio.CancelScope(shield=True):
await self._main_loop_exit()
self.__blocking_result_queue.put(None)
nursery.cancel_scope.cancel()
async def wrapper(asyncfn, *args):
nonlocal result
try:
await asyncfn(*args)
except Exception as e:
result = outcome.Error(e)
event.set()
def test_outcomes_unwrap_raises_qt_error_over_trio_none():
"""Unwrapping an Outcomes prioritizes a Qt error over a Trio None."""
class LocalUniqueException(Exception):
pass
this_outcome = qtrio.Outcomes(qt=outcome.Error(LocalUniqueException()))
with pytest.raises(LocalUniqueException):
this_outcome.unwrap()
def notify_closing(self, handle):
handle = _get_base_socket(handle)
waiters = self._afd_waiters.get(handle)
if waiters is not None:
if waiters.read_task is not None:
_core.reschedule(
waiters.read_task,
outcome.Error(_core.ClosedResourceError())
)
waiters.read_task = None
if waiters.write_task is not None:
_core.reschedule(
waiters.write_task,
outcome.Error(_core.ClosedResourceError())
)
waiters.write_task = None
self._refresh_afd(handle)
def notify_socket_close(self, sock):
if not isinstance(sock, int):
sock = sock.fileno()
for mode in ["read", "write"]:
if sock in self._socket_waiters[mode]:
task = self._socket_waiters[mode].pop(sock)
exc = _core.ClosedResourceError(
"another task closed this socket")
_core.reschedule(task, outcome.Error(exc))
async def _second_runner(self, queue: RequestQueue[int, int]) -> None:
while True:
many = await queue.get_many()
for val, coro in many[::-1]:
try:
result = await self.queue.request(val + 100)
except Exception as e:
coro.resume(outcome.Error(e))
else:
coro.resume(outcome.Value(result))
def notify_socket_close(self, sock):
if type(sock) is not stdlib_socket.socket:
raise TypeError("need a stdlib socket")
for mode in ["read", "write"]:
if sock in self._socket_waiters[mode]:
task = self._socket_waiters[mode].pop(sock)
exc = _core.ClosedResourceError(
"another task closed this socket")
_core.reschedule(task, outcome.Error(exc))
async def _first_runner(self, queue: RequestQueue) -> None:
while True:
many = await queue.get_many()
for val, coro in many[::-1]:
if val == 1337:
try:
failing_function(x) # type: ignore
except Exception as e:
coro.resume(outcome.Error(e))
else:
coro.resume(outcome.Value(val + 10))
def outcome_from_application_return_code(return_code: int) -> outcome.Outcome:
"""Create either an :class:`outcome.Value` in the case of a 0 `return_code` or an
:class:`outcome.Error` with a :class:`ReturnCodeError` otherwise.
Args:
return_code: The return code to be processed.
"""
if return_code == 0:
return outcome.Value(return_code)
return outcome.Error(qtrio.ReturnCodeError(return_code))
async def consume_next():
try:
item = await async_generator.__anext__()
result = outcome.Value(value=item)
except StopAsyncIteration:
result = outcome.Value(value=STOP)
except asyncio.CancelledError:
# Once we are cancelled, we do not call reschedule() anymore
return
except Exception as e:
result = outcome.Error(error=e)
trio.hazmat.reschedule(task, result)
async def receiver():
async with child_recv_chan:
async for i in child_recv_chan:
# Just consume all results from the channel until exhausted
pass
# And then wrap up the result and push it to the parent channel
errors = [e.error for e in result_list if isinstance(e, outcome.Error)]
if len(errors) > 0:
result = outcome.Error(trio.MultiError(errors))
else:
result = outcome.Value([o.unwrap() for o in result_list])
async with parent_send_chan:
await parent_send_chan.send(result)
def callback(q, afn, args):
@disable_ki_protection
async def unprotected_afn():
coro = coroutine_or_error(afn, *args)
return await coro
async def await_in_trio_thread_task():
q.put_nowait(await outcome.acapture(unprotected_afn))
try:
trio.lowlevel.spawn_system_task(await_in_trio_thread_task,
name=afn)
except RuntimeError: # system nursery is closed
q.put_nowait(
outcome.Error(
trio.RunFinishedError("system nursery is closed")))
def wake_all(waiters, exc):
try:
current_task = _core.current_task()
except RuntimeError:
current_task = None
raise_at_end = False
for attr_name in ["read_task", "write_task"]:
task = getattr(waiters, attr_name)
if task is not None:
if task is current_task:
raise_at_end = True
else:
_core.reschedule(task, outcome.Error(copy.copy(exc)))
setattr(waiters, attr_name, None)
if raise_at_end:
raise exc
async def consume_next():
t = sniffio.current_async_library_cvar.set("asyncio")
try:
item = await async_generator.__anext__()
result = outcome.Value(value=item)
except StopAsyncIteration:
result = outcome.Value(value=STOP)
except asyncio.CancelledError:
# Once we are cancelled, we do not call reschedule() anymore
return
except Exception as e:
result = outcome.Error(error=e)
finally:
sniffio.current_async_library_cvar.reset(t)
trio.hazmat.reschedule(task, result)
def notify_closing(self, fd):
if not isinstance(fd, int):
fd = fd.fileno()
for filter in [select.KQ_FILTER_READ, select.KQ_FILTER_WRITE]:
key = (fd, filter)
receiver = self._registered.get(key)
if receiver is None:
continue
if type(receiver) is _core.Task:
event = select.kevent(fd, filter, select.KQ_EV_DELETE)
self._kqueue.control([event], 0)
exc = _core.ClosedResourceError("another task closed this fd")
_core.reschedule(receiver, outcome.Error(exc))
del self._registered[key]
else:
# XX this is an interesting example of a case where being able
# to close a queue would be useful...
raise NotImplementedError(
"can't close an fd that monitor_kevent is using")
async def _msg_in(self, msg):
if msg.get("result",()) and msg["result"][0] != "Pong":
self.__logger.debug("IN %r",msg)
seq = msg.get("seq",None)
if seq is not None:
try:
ev = self._replies[seq]
except KeyError:
self.__logger.warning("Unknown Reply %r",msg)
return
else:
if not isinstance(ev, trio.Event):
self.__logger.warning("Dup Reply %r",msg)
return
try:
self._replies[seq] = outcome.Value(msg["result"])
except KeyError:
self._replies[seq] = outcome.Error(RuntimeError(msg.get("error","Unknown error")))
ev.set()
else:
await self._dispatch(msg)
self.__logger.debug("IN done")
def interceptor(underlying_coro): # type: ignore
nonlocal result, delivered
try:
next_trap = "hello"
while True:
trap_result = yield next_trap
if isinstance(trap_result, outcome.Error):
if isinstance(trap_result.error, MonitorKill):
delivered = True
next_trap = underlying_coro.send(trap_result)
if not delivered:
next_trap = underlying_coro.send(
outcome.Error(MonitorKill()))
delivered = True
except StopIteration as ex:
return ex.value
except MonitorKill as ex:
result = ex
except BaseException as ex:
result = ex
raise
finally:
done.set()
async def set_error(self, exc):
"""Set the internal flag value to True, and wake any waiting tasks."""
self.value = outcome.Error(exc)
await self.event.set()
def interrupt(task):
exc = _core.ClosedResourceError("another task closed this fd")
_core.reschedule(task, outcome.Error(exc))
async def set_error(self, err):
await self._q_w.send(outcome.Error(err))
def _greenback_shim(orig_coro: Coroutine[Any, Any, Any]) -> Generator[Any, Any, Any]:
# In theory this could be written as a simpler function that uses
# _greenback_shim_sync():
#
# next_yield = "ready"
# while True:
# try:
# target = partial(orig_coro.send, (yield next_yield))
# except BaseException as ex:
# target = partial(orig_coro.throw, ex)
# try:
# next_yield = yield from _greenback_shim_sync(target)
# except StopIteration as ex:
# return ex.value
#
# In practice, this doesn't work that well: _greenback_shim_sync()
# has a hard time raising StopIteration, because it's a generator,
# and unrolling it into a non-generator iterable makes it slower.
# So we'll accept a bit of code duplication.
parent_greenlet = greenlet.getcurrent()
# The greenlet in which each send() or throw() call will occur.
child_greenlet: Optional[greenlet.greenlet] = None
# The contextvars.Context that we have most recently seen as active
# for this task and propagated to child_greenlet
curr_ctx: Optional[contextvars.Context] = None
# The next thing we plan to yield to the event loop. (The first yield
# goes to ensure_portal() rather than to the event loop, so we use a
# string that is unlikely to be a valid event loop trap.)
next_yield: Any = "ready"
# The next thing we plan to send to the original coroutine. This is an
# outcome representing the value or error that the event loop resumed
# us with.
next_send: outcome.Outcome[Any]
while True:
try:
# Normally we send to orig_coro whatever the event loop sent us
next_send = outcome.Value((yield next_yield))
except BaseException as ex:
# If the event loop resumed us with an error, we forward that error
next_send = outcome.Error(ex)
try:
if not child_greenlet:
# Start a new send() or throw() call on the original coroutine.
child_greenlet = greenlet.greenlet(next_send.send)
switch_arg: Any = orig_coro
else:
# Resume the previous send() or throw() call, which is currently
# at a simulated yield point in a greenback.await_() call.
switch_arg = next_send
if (
greenlet_needs_context_fixup
and parent_greenlet.gr_context is not curr_ctx
and child_greenlet.gr_context is curr_ctx
):
# Make sure the child greenlet's contextvars context
# is the same as our own, even if our own context
# changes (such as via trio.Task.context assignment),
# unless the child greenlet appears to have changed
# its context privately through a call to Context.run().
#
# Note 'parent_greenlet.gr_context' here is just a
# portable way of getting the current contextvars
# context, which is not exposed by the contextvars
# module directly (copy_context() returns a copy, not
# a new reference to the original). Upon initial
# creation of child_greenlet, curr_ctx and
# child_greenlet.gr_context will both be None, so this
# condition works for that case too.
child_greenlet.gr_context = curr_ctx = parent_greenlet.gr_context
next_yield = child_greenlet.switch(switch_arg)
if child_greenlet.dead:
# The send() or throw() call completed so we need to
# create a new greenlet for the next one.
child_greenlet = curr_ctx = None
except StopIteration as ex:
# The underlying coroutine completed, so we forward its return value.
return ex.value
def _greenback_shim_sync(target: Callable[[], Any]) -> Generator[Any, Any, Any]:
"""Run target(), forwarding the event loop traps and responses necessary
to implement any await_() calls that it makes.
This is only a little bit faster than using greenback_shim() plus a
sync-to-async wrapper -- maybe 2us faster for the entire call,
so it only matters when you're scoping the portal to a very small
range. We ship it anyway because it's easier to understand than
the async-compatible _greenback_shim(), and helps with understanding
the latter.
"""
parent_greenlet = greenlet.getcurrent()
curr_ctx = None
# The greenlet in which we run target().
child_greenlet = greenlet.greenlet(target)
# The next thing we plan to yield to the event loop.
next_yield: Any
# The next thing we plan to send via greenlet.switch(). This is an
# outcome representing the value or error that the event loop resumed
# us with. Initially None for the very first zero-argument switch().
next_send: Optional[outcome.Outcome[Any]] = None
while True:
if (
greenlet_needs_context_fixup
and parent_greenlet.gr_context is not curr_ctx
and child_greenlet.gr_context is curr_ctx
):
# Make sure the child greenlet's contextvars context
# is the same as our own, even if our own context
# changes (such as via trio.Task.context assignment),
# unless the child greenlet appears to have changed
# its context privately through a call to Context.run().
#
# Note 'parent_greenlet.gr_context' here is just a
# portable way of getting the current contextvars
# context, which is not exposed by the contextvars
# module directly (copy_context() returns a copy, not
# a new reference to the original). Upon initial
# creation of child_greenlet, curr_ctx and
# child_greenlet.gr_context will both be None, so this
# condition works for that case too.
child_greenlet.gr_context = curr_ctx = parent_greenlet.gr_context
if next_send is None:
next_yield = child_greenlet.switch()
else:
next_yield = child_greenlet.switch(next_send)
if child_greenlet.dead:
# target() returned, so next_yield is its return value, not an
# event loop trap. (If it exits with an exception, that exception
# will propagate out of switch() and thus out of the loop, which
# is what we want.)
return next_yield
try:
# Normally we send to orig_coro whatever the event loop sent us
next_send = outcome.Value((yield next_yield))
except BaseException as ex:
# If the event loop resumed us with an error, we forward that error
next_send = outcome.Error(ex)
def test_outcome_from_application_return_code_error():
"""Non-zero return code result in outcome.Error"""
result = qtrio._core.outcome_from_application_return_code(return_code=-1)
assert result == outcome.Error(qtrio.ReturnCodeError(-1))
def throw(self, exn: BaseException) -> None:
return self.resume(outcome.Error(exn))
async def set_error(self, exc):
"""Set the result to raise this exceptio, and wake any waiting task.
"""
self.value = outcome.Error(exc)
await self.event.set()
def socket_check(what, sock):
try:
select([sock], [sock], [sock], 0)
except OSError as exc:
socket_ready(what, sock, outcome.Error(exc))
def resume(self, value: Outcome[SendType]) -> None:
if self.cancelled:
# discard the result - not great, obviously...
logger.debug("TrioContinuation(%s): resumed after cancellation",
self.task)
return
if self.on_stack:
logger.debug("TrioContinuation(%s): immediately resumed with %s",
self.task, value)
# This will happen if the function passed to shift immediately resumes the
# continuation. With trio, we run the function passed to shift on the
# coroutine that's being suspended. So we can't resume the coroutine here,
# since it's already running. Instead we'll save the outcome, and in shift()
# we check saved_send and just return immediately if it's set. This is not
# normal shift/reset semantics but it's the best we can do with how trio is
# structured.
self.saved_send = value
return
resuming_task = GLOBAL_RUN_CONTEXT.task
runner = GLOBAL_RUN_CONTEXT.runner
logger.debug("TrioContinuation(%s): resuming with %s", self.task,
value)
global _under_coro_runner
try:
previous_runner = _under_coro_runner
_under_coro_runner = Runner.TRIO
# We have to temporarily set GLOBAL_RUN_CONTEXT.task to the task that is being
# resumed; after all, that's the task that's really going to be running. This
# wouldn't be necessary if we had proper dynamically scoped variables in
# Python :(
GLOBAL_RUN_CONTEXT.task = self.task
# a little bit of reschedule(), before we run the task
self.task._abort_func = None
self.task.custom_sleep_data = None
try:
msg = self.task.context.run(self.task.coro.send, value)
except StopIteration as exn:
logger.debug("TrioContinuation(%s): return %s", self.task,
exn.value)
GLOBAL_RUN_CONTEXT.runner.task_exited(self.task,
outcome.Value(exn.value))
return
except BaseException as exn:
logger.debug("TrioContinuation(%s): raised %s", self.task, exn)
exn = exn.with_traceback(exn.__traceback__
and exn.__traceback__.tb_next)
GLOBAL_RUN_CONTEXT.runner.task_exited(self.task,
outcome.Error(exn))
return
logger.debug("TrioContinuation(%s): yield %s", self.task, msg)
finally:
_under_coro_runner = previous_runner
GLOBAL_RUN_CONTEXT.task = resuming_task
if msg is CancelShieldedCheckpoint:
runner.reschedule(self.task)
elif type(msg) is WaitTaskRescheduled:
self.task._abort_func = msg.abort_func
if runner.ki_pending and self.task is runner.main_task:
self.task._attempt_delivery_of_pending_ki()
self.task._attempt_delivery_of_any_pending_cancel()
elif type(msg) is PermanentlyDetachCoroutineObject:
runner.task_exited(self.task, msg.final_outcome)
else:
raise TypeError("bad yield from continuation", msg)