1149 lines
38 KiB
Python

from __future__ import annotations
import contextvars
import queue as stdlib_queue
import re
import sys
import threading
import time
import weakref
from functools import partial
from typing import (
TYPE_CHECKING,
AsyncGenerator,
Awaitable,
Callable,
List,
NoReturn,
Tuple,
Type,
TypeVar,
Union,
)
import pytest
import sniffio
from .. import (
CancelScope,
CapacityLimiter,
Event,
_core,
fail_after,
move_on_after,
sleep,
sleep_forever,
)
from .._core._tests.test_ki import ki_self
from .._core._tests.tutil import slow
from .._threads import (
active_thread_count,
current_default_thread_limiter,
from_thread_check_cancelled,
from_thread_run,
from_thread_run_sync,
to_thread_run_sync,
wait_all_threads_completed,
)
from ..testing import wait_all_tasks_blocked
if TYPE_CHECKING:
from outcome import Outcome
from ..lowlevel import Task
RecordType = List[Tuple[str, Union[threading.Thread, Type[BaseException]]]]
T = TypeVar("T")
async def test_do_in_trio_thread() -> None:
trio_thread = threading.current_thread()
async def check_case(
do_in_trio_thread: Callable[..., threading.Thread],
fn: Callable[..., T | Awaitable[T]],
expected: tuple[str, T],
trio_token: _core.TrioToken | None = None,
) -> None:
record: RecordType = []
def threadfn() -> None:
try:
record.append(("start", threading.current_thread()))
x = do_in_trio_thread(fn, record, trio_token=trio_token)
record.append(("got", x))
except BaseException as exc:
print(exc)
record.append(("error", type(exc)))
child_thread = threading.Thread(target=threadfn, daemon=True)
child_thread.start()
while child_thread.is_alive():
print("yawn")
await sleep(0.01)
assert record == [("start", child_thread), ("f", trio_thread), expected]
token = _core.current_trio_token()
def f1(record: RecordType) -> int:
assert not _core.currently_ki_protected()
record.append(("f", threading.current_thread()))
return 2
await check_case(from_thread_run_sync, f1, ("got", 2), trio_token=token)
def f2(record: RecordType) -> NoReturn:
assert not _core.currently_ki_protected()
record.append(("f", threading.current_thread()))
raise ValueError
await check_case(from_thread_run_sync, f2, ("error", ValueError), trio_token=token)
async def f3(record: RecordType) -> int:
assert not _core.currently_ki_protected()
await _core.checkpoint()
record.append(("f", threading.current_thread()))
return 3
await check_case(from_thread_run, f3, ("got", 3), trio_token=token)
async def f4(record: RecordType) -> NoReturn:
assert not _core.currently_ki_protected()
await _core.checkpoint()
record.append(("f", threading.current_thread()))
raise KeyError
await check_case(from_thread_run, f4, ("error", KeyError), trio_token=token)
async def test_do_in_trio_thread_from_trio_thread() -> None:
with pytest.raises(RuntimeError):
from_thread_run_sync(lambda: None) # pragma: no branch
async def foo() -> None: # pragma: no cover
pass
with pytest.raises(RuntimeError):
from_thread_run(foo)
def test_run_in_trio_thread_ki() -> None:
# if we get a control-C during a run_in_trio_thread, then it propagates
# back to the caller (slick!)
record = set()
async def check_run_in_trio_thread() -> None:
token = _core.current_trio_token()
def trio_thread_fn() -> None:
print("in Trio thread")
assert not _core.currently_ki_protected()
print("ki_self")
try:
ki_self()
finally:
import sys
print("finally", sys.exc_info())
async def trio_thread_afn() -> None:
trio_thread_fn()
def external_thread_fn() -> None:
try:
print("running")
from_thread_run_sync(trio_thread_fn, trio_token=token)
except KeyboardInterrupt:
print("ok1")
record.add("ok1")
try:
from_thread_run(trio_thread_afn, trio_token=token)
except KeyboardInterrupt:
print("ok2")
record.add("ok2")
thread = threading.Thread(target=external_thread_fn)
thread.start()
print("waiting")
while thread.is_alive(): # noqa: ASYNC110
await sleep(0.01) # Fine to poll in tests.
print("waited, joining")
thread.join()
print("done")
_core.run(check_run_in_trio_thread)
assert record == {"ok1", "ok2"}
def test_await_in_trio_thread_while_main_exits() -> None:
record = []
ev = Event()
async def trio_fn() -> None:
record.append("sleeping")
ev.set()
await _core.wait_task_rescheduled(lambda _: _core.Abort.SUCCEEDED)
def thread_fn(token: _core.TrioToken) -> None:
try:
from_thread_run(trio_fn, trio_token=token)
except _core.Cancelled:
record.append("cancelled")
async def main() -> threading.Thread:
token = _core.current_trio_token()
thread = threading.Thread(target=thread_fn, args=(token,))
thread.start()
await ev.wait()
assert record == ["sleeping"]
return thread
thread = _core.run(main)
thread.join()
assert record == ["sleeping", "cancelled"]
async def test_named_thread() -> None:
ending = " from trio._tests.test_threads.test_named_thread"
def inner(name: str = "inner" + ending) -> threading.Thread:
assert threading.current_thread().name == name
return threading.current_thread()
def f(name: str) -> Callable[[None], threading.Thread]:
return partial(inner, name)
# test defaults
await to_thread_run_sync(inner)
await to_thread_run_sync(inner, thread_name=None)
# functools.partial doesn't have __name__, so defaults to None
await to_thread_run_sync(f("None" + ending))
# test that you can set a custom name, and that it's reset afterwards
async def test_thread_name(name: str) -> None:
thread = await to_thread_run_sync(f(name), thread_name=name)
assert re.match("Trio thread [0-9]*", thread.name)
await test_thread_name("")
await test_thread_name("fobiedoo")
await test_thread_name("name_longer_than_15_characters")
await test_thread_name("💙")
def _get_thread_name(ident: int | None = None) -> str | None:
import ctypes
import ctypes.util
libpthread_path = ctypes.util.find_library("pthread")
if not libpthread_path:
# musl includes pthread functions directly in libc.so
# (but note that find_library("c") does not work on musl,
# see: https://github.com/python/cpython/issues/65821)
# so try that library instead
# if it doesn't exist, CDLL() will fail below
libpthread_path = "libc.so"
try:
libpthread = ctypes.CDLL(libpthread_path)
except Exception:
print(f"no pthread on {sys.platform}")
return None
pthread_getname_np = getattr(libpthread, "pthread_getname_np", None)
# this should never fail on any platforms afaik
assert pthread_getname_np
# thankfully getname signature doesn't differ between platforms
pthread_getname_np.argtypes = [
ctypes.c_void_p,
ctypes.c_char_p,
ctypes.c_size_t,
]
pthread_getname_np.restype = ctypes.c_int
name_buffer = ctypes.create_string_buffer(b"", size=16)
if ident is None:
ident = threading.get_ident()
assert pthread_getname_np(ident, name_buffer, 16) == 0
try:
return name_buffer.value.decode()
except UnicodeDecodeError as e: # pragma: no cover
# used for debugging when testing via CI
pytest.fail(f"value: {name_buffer.value!r}, exception: {e}")
# test os thread naming
# this depends on pthread being available, which is the case on 99.9% of linux machines
# and most mac machines. So unless the platform is linux it will just skip
# in case it fails to fetch the os thread name.
async def test_named_thread_os() -> None:
def inner(name: str) -> threading.Thread:
os_thread_name = _get_thread_name()
if os_thread_name is None and sys.platform != "linux":
pytest.skip(f"no pthread OS support on {sys.platform}")
else:
assert os_thread_name == name[:15]
return threading.current_thread()
def f(name: str) -> Callable[[None], threading.Thread]:
return partial(inner, name)
# test defaults
default = "None from trio._tests.test_threads.test_named_thread"
await to_thread_run_sync(f(default))
await to_thread_run_sync(f(default), thread_name=None)
# test that you can set a custom name, and that it's reset afterwards
async def test_thread_name(name: str, expected: str | None = None) -> None:
if expected is None:
expected = name
thread = await to_thread_run_sync(f(expected), thread_name=name)
os_thread_name = _get_thread_name(thread.ident)
assert os_thread_name is not None, "should skip earlier if this is the case"
assert re.match("Trio thread [0-9]*", os_thread_name)
await test_thread_name("")
await test_thread_name("fobiedoo")
await test_thread_name("name_longer_than_15_characters")
await test_thread_name("💙", expected="?")
async def test_has_pthread_setname_np() -> None:
from trio._core._thread_cache import get_os_thread_name_func
k = get_os_thread_name_func()
if k is None:
assert sys.platform != "linux"
pytest.skip(f"no pthread_setname_np on {sys.platform}")
async def test_run_in_worker_thread() -> None:
trio_thread = threading.current_thread()
def f(x: T) -> tuple[T, threading.Thread]:
return (x, threading.current_thread())
x, child_thread = await to_thread_run_sync(f, 1)
assert x == 1
assert child_thread != trio_thread
def g() -> NoReturn:
raise ValueError(threading.current_thread())
with pytest.raises(
ValueError,
match=r"^<Thread\(Trio thread \d+, started daemon \d+\)>$",
) as excinfo:
await to_thread_run_sync(g)
print(excinfo.value.args)
assert excinfo.value.args[0] != trio_thread
async def test_run_in_worker_thread_cancellation() -> None:
register: list[str | None] = [None]
def f(q: stdlib_queue.Queue[str]) -> None:
# Make the thread block for a controlled amount of time
register[0] = "blocking"
q.get()
register[0] = "finished"
async def child(q: stdlib_queue.Queue[None], abandon_on_cancel: bool) -> None:
record.append("start")
try:
return await to_thread_run_sync(f, q, abandon_on_cancel=abandon_on_cancel)
finally:
record.append("exit")
record: list[str] = []
q: stdlib_queue.Queue[None] = stdlib_queue.Queue()
async with _core.open_nursery() as nursery:
nursery.start_soon(child, q, True)
# Give it a chance to get started. (This is important because
# to_thread_run_sync does a checkpoint_if_cancelled before
# blocking on the thread, and we don't want to trigger this.)
await wait_all_tasks_blocked()
assert record == ["start"]
# Then cancel it.
nursery.cancel_scope.cancel()
# The task exited, but the thread didn't:
assert register[0] != "finished"
# Put the thread out of its misery:
q.put(None)
while register[0] != "finished":
time.sleep(0.01) # noqa: ASYNC251 # Need to wait for OS thread
# This one can't be cancelled
record = []
register[0] = None
async with _core.open_nursery() as nursery:
nursery.start_soon(child, q, False)
await wait_all_tasks_blocked()
nursery.cancel_scope.cancel()
with _core.CancelScope(shield=True):
for _ in range(10):
await _core.checkpoint()
# It's still running
assert record == ["start"]
q.put(None)
# Now it exits
# But if we cancel *before* it enters, the entry is itself a cancellation
# point
with _core.CancelScope() as scope:
scope.cancel()
await child(q, False)
assert scope.cancelled_caught
# Make sure that if trio.run exits, and then the thread finishes, then that's
# handled gracefully. (Requires that the thread result machinery be prepared
# for call_soon to raise RunFinishedError.)
def test_run_in_worker_thread_abandoned(
capfd: pytest.CaptureFixture[str],
monkeypatch: pytest.MonkeyPatch,
) -> None:
monkeypatch.setattr(_core._thread_cache, "IDLE_TIMEOUT", 0.01)
q1: stdlib_queue.Queue[None] = stdlib_queue.Queue()
q2: stdlib_queue.Queue[threading.Thread] = stdlib_queue.Queue()
def thread_fn() -> None:
q1.get()
q2.put(threading.current_thread())
async def main() -> None:
async def child() -> None:
await to_thread_run_sync(thread_fn, abandon_on_cancel=True)
async with _core.open_nursery() as nursery:
nursery.start_soon(child)
await wait_all_tasks_blocked()
nursery.cancel_scope.cancel()
_core.run(main)
q1.put(None)
# This makes sure:
# - the thread actually ran
# - that thread has finished before we check for its output
thread = q2.get()
while thread.is_alive():
time.sleep(0.01) # pragma: no cover
# Make sure we don't have a "Exception in thread ..." dump to the console:
out, err = capfd.readouterr()
assert "Exception in thread" not in out
assert "Exception in thread" not in err
@pytest.mark.parametrize("MAX", [3, 5, 10])
@pytest.mark.parametrize("cancel", [False, True])
@pytest.mark.parametrize("use_default_limiter", [False, True])
async def test_run_in_worker_thread_limiter(
MAX: int,
cancel: bool,
use_default_limiter: bool,
) -> None:
# This test is a bit tricky. The goal is to make sure that if we set
# limiter=CapacityLimiter(MAX), then in fact only MAX threads are ever
# running at a time, even if there are more concurrent calls to
# to_thread_run_sync, and even if some of those are cancelled. And
# also to make sure that the default limiter actually limits.
COUNT = 2 * MAX
gate = threading.Event()
lock = threading.Lock()
if use_default_limiter:
c = current_default_thread_limiter()
orig_total_tokens = c.total_tokens
c.total_tokens = MAX
limiter_arg = None
else:
c = CapacityLimiter(MAX)
orig_total_tokens = MAX
limiter_arg = c
try:
# We used to use regular variables and 'nonlocal' here, but it turns
# out that it's not safe to assign to closed-over variables that are
# visible in multiple threads, at least as of CPython 3.10 and PyPy
# 7.3:
#
# https://bugs.python.org/issue30744
# https://bitbucket.org/pypy/pypy/issues/2591/
#
# Mutating them in-place is OK though (as long as you use proper
# locking etc.).
class state:
ran: int
high_water: int
running: int
parked: int
state.ran = 0
state.high_water = 0
state.running = 0
state.parked = 0
token = _core.current_trio_token()
def thread_fn(cancel_scope: CancelScope) -> None:
print("thread_fn start")
from_thread_run_sync(cancel_scope.cancel, trio_token=token)
with lock:
state.ran += 1
state.running += 1
state.high_water = max(state.high_water, state.running)
# The Trio thread below watches this value and uses it as a
# signal that all the stats calculations have finished.
state.parked += 1
gate.wait()
with lock:
state.parked -= 1
state.running -= 1
print("thread_fn exiting")
async def run_thread(event: Event) -> None:
with _core.CancelScope() as cancel_scope:
await to_thread_run_sync(
thread_fn,
cancel_scope,
abandon_on_cancel=cancel,
limiter=limiter_arg,
)
print("run_thread finished, cancelled:", cancel_scope.cancelled_caught)
event.set()
async with _core.open_nursery() as nursery:
print("spawning")
events = []
for _ in range(COUNT):
events.append(Event())
nursery.start_soon(run_thread, events[-1])
await wait_all_tasks_blocked()
# In the cancel case, we in particular want to make sure that the
# cancelled tasks don't release the semaphore. So let's wait until
# at least one of them has exited, and that everything has had a
# chance to settle down from this, before we check that everyone
# who's supposed to be waiting is waiting:
if cancel:
print("waiting for first cancellation to clear")
await events[0].wait()
await wait_all_tasks_blocked()
# Then wait until the first MAX threads are parked in gate.wait(),
# and the next MAX threads are parked on the semaphore, to make
# sure no-one is sneaking past, and to make sure the high_water
# check below won't fail due to scheduling issues. (It could still
# fail if too many threads are let through here.)
while ( # noqa: ASYNC110
state.parked != MAX or c.statistics().tasks_waiting != MAX
):
await sleep(0.01) # pragma: no cover
# Then release the threads
gate.set()
assert state.high_water == MAX
if cancel:
# Some threads might still be running; need to wait to them to
# finish before checking that all threads ran. We can do this
# using the CapacityLimiter.
while c.borrowed_tokens > 0: # noqa: ASYNC110
await sleep(0.01) # pragma: no cover
assert state.ran == COUNT
assert state.running == 0
finally:
c.total_tokens = orig_total_tokens
async def test_run_in_worker_thread_custom_limiter() -> None:
# Basically just checking that we only call acquire_on_behalf_of and
# release_on_behalf_of, since that's part of our documented API.
record = []
class CustomLimiter:
async def acquire_on_behalf_of(self, borrower: Task) -> None:
record.append("acquire")
self._borrower = borrower
def release_on_behalf_of(self, borrower: Task) -> None:
record.append("release")
assert borrower == self._borrower
# TODO: should CapacityLimiter have an abc or protocol so users can modify it?
# because currently it's `final` so writing code like this is not allowed.
await to_thread_run_sync(lambda: None, limiter=CustomLimiter()) # type: ignore[arg-type]
assert record == ["acquire", "release"]
async def test_run_in_worker_thread_limiter_error() -> None:
record = []
class BadCapacityLimiter:
async def acquire_on_behalf_of(self, borrower: Task) -> None:
record.append("acquire")
def release_on_behalf_of(self, borrower: Task) -> NoReturn:
record.append("release")
raise ValueError("release on behalf")
bs = BadCapacityLimiter()
with pytest.raises(ValueError, match="^release on behalf$") as excinfo:
await to_thread_run_sync(lambda: None, limiter=bs) # type: ignore[arg-type]
assert excinfo.value.__context__ is None
assert record == ["acquire", "release"]
record = []
# If the original function raised an error, then the semaphore error
# chains with it
d: dict[str, object] = {}
with pytest.raises(ValueError, match="^release on behalf$") as excinfo:
await to_thread_run_sync(lambda: d["x"], limiter=bs) # type: ignore[arg-type]
assert isinstance(excinfo.value.__context__, KeyError)
assert record == ["acquire", "release"]
async def test_run_in_worker_thread_fail_to_spawn(
monkeypatch: pytest.MonkeyPatch,
) -> None:
# Test the unlikely but possible case where trying to spawn a thread fails
def bad_start(self: object, *args: object) -> NoReturn:
raise RuntimeError("the engines canna take it captain")
monkeypatch.setattr(_core._thread_cache.ThreadCache, "start_thread_soon", bad_start)
limiter = current_default_thread_limiter()
assert limiter.borrowed_tokens == 0
# We get an appropriate error, and the limiter is cleanly released
with pytest.raises(RuntimeError) as excinfo:
await to_thread_run_sync(lambda: None) # pragma: no cover
assert "engines" in str(excinfo.value)
assert limiter.borrowed_tokens == 0
async def test_trio_to_thread_run_sync_token() -> None:
# Test that to_thread_run_sync automatically injects the current trio token
# into a spawned thread
def thread_fn() -> _core.TrioToken:
callee_token = from_thread_run_sync(_core.current_trio_token)
return callee_token
caller_token = _core.current_trio_token()
callee_token = await to_thread_run_sync(thread_fn)
assert callee_token == caller_token
async def test_trio_to_thread_run_sync_expected_error() -> None:
# Test correct error when passed async function
async def async_fn() -> None: # pragma: no cover
pass
with pytest.raises(TypeError, match="expected a sync function"):
await to_thread_run_sync(async_fn) # type: ignore[unused-coroutine]
trio_test_contextvar: contextvars.ContextVar[str] = contextvars.ContextVar(
"trio_test_contextvar",
)
async def test_trio_to_thread_run_sync_contextvars() -> None:
trio_thread = threading.current_thread()
trio_test_contextvar.set("main")
def f() -> tuple[str, threading.Thread]:
value = trio_test_contextvar.get()
with pytest.raises(sniffio.AsyncLibraryNotFoundError):
sniffio.current_async_library()
return (value, threading.current_thread())
value, child_thread = await to_thread_run_sync(f)
assert value == "main"
assert child_thread != trio_thread
def g() -> tuple[str, str, threading.Thread]:
parent_value = trio_test_contextvar.get()
trio_test_contextvar.set("worker")
inner_value = trio_test_contextvar.get()
with pytest.raises(sniffio.AsyncLibraryNotFoundError):
sniffio.current_async_library()
return (
parent_value,
inner_value,
threading.current_thread(),
)
parent_value, inner_value, child_thread = await to_thread_run_sync(g)
current_value = trio_test_contextvar.get()
assert parent_value == "main"
assert inner_value == "worker"
assert current_value == "main", (
"The contextvar value set on the worker would not propagate back to the main"
" thread"
)
assert sniffio.current_async_library() == "trio"
async def test_trio_from_thread_run_sync() -> None:
# Test that to_thread_run_sync correctly "hands off" the trio token to
# trio.from_thread.run_sync()
def thread_fn_1() -> float:
trio_time = from_thread_run_sync(_core.current_time)
return trio_time
trio_time = await to_thread_run_sync(thread_fn_1)
assert isinstance(trio_time, float)
# Test correct error when passed async function
async def async_fn() -> None: # pragma: no cover
pass
def thread_fn_2() -> None:
from_thread_run_sync(async_fn) # type: ignore[unused-coroutine]
with pytest.raises(TypeError, match="expected a synchronous function"):
await to_thread_run_sync(thread_fn_2)
async def test_trio_from_thread_run() -> None:
# Test that to_thread_run_sync correctly "hands off" the trio token to
# trio.from_thread.run()
record = []
async def back_in_trio_fn() -> None:
_core.current_time() # implicitly checks that we're in trio
record.append("back in trio")
def thread_fn() -> None:
record.append("in thread")
from_thread_run(back_in_trio_fn)
await to_thread_run_sync(thread_fn)
assert record == ["in thread", "back in trio"]
# Test correct error when passed sync function
def sync_fn() -> None: # pragma: no cover
pass
with pytest.raises(TypeError, match="appears to be synchronous"):
await to_thread_run_sync(from_thread_run, sync_fn)
async def test_trio_from_thread_token() -> None:
# Test that to_thread_run_sync and spawned trio.from_thread.run_sync()
# share the same Trio token
def thread_fn() -> _core.TrioToken:
callee_token = from_thread_run_sync(_core.current_trio_token)
return callee_token
caller_token = _core.current_trio_token()
callee_token = await to_thread_run_sync(thread_fn)
assert callee_token == caller_token
async def test_trio_from_thread_token_kwarg() -> None:
# Test that to_thread_run_sync and spawned trio.from_thread.run_sync() can
# use an explicitly defined token
def thread_fn(token: _core.TrioToken) -> _core.TrioToken:
callee_token = from_thread_run_sync(_core.current_trio_token, trio_token=token)
return callee_token
caller_token = _core.current_trio_token()
callee_token = await to_thread_run_sync(thread_fn, caller_token)
assert callee_token == caller_token
async def test_from_thread_no_token() -> None:
# Test that a "raw call" to trio.from_thread.run() fails because no token
# has been provided
with pytest.raises(RuntimeError):
from_thread_run_sync(_core.current_time)
async def test_trio_from_thread_run_sync_contextvars() -> None:
trio_test_contextvar.set("main")
def thread_fn() -> tuple[str, str, str, str, str]:
thread_parent_value = trio_test_contextvar.get()
trio_test_contextvar.set("worker")
thread_current_value = trio_test_contextvar.get()
with pytest.raises(sniffio.AsyncLibraryNotFoundError):
sniffio.current_async_library()
def back_in_main() -> tuple[str, str]:
back_parent_value = trio_test_contextvar.get()
trio_test_contextvar.set("back_in_main")
back_current_value = trio_test_contextvar.get()
assert sniffio.current_async_library() == "trio"
return back_parent_value, back_current_value
back_parent_value, back_current_value = from_thread_run_sync(back_in_main)
thread_after_value = trio_test_contextvar.get()
with pytest.raises(sniffio.AsyncLibraryNotFoundError):
sniffio.current_async_library()
return (
thread_parent_value,
thread_current_value,
thread_after_value,
back_parent_value,
back_current_value,
)
(
thread_parent_value,
thread_current_value,
thread_after_value,
back_parent_value,
back_current_value,
) = await to_thread_run_sync(thread_fn)
current_value = trio_test_contextvar.get()
assert current_value == thread_parent_value == "main"
assert thread_current_value == back_parent_value == thread_after_value == "worker"
assert sniffio.current_async_library() == "trio"
assert back_current_value == "back_in_main"
async def test_trio_from_thread_run_contextvars() -> None:
trio_test_contextvar.set("main")
def thread_fn() -> tuple[str, str, str, str, str]:
thread_parent_value = trio_test_contextvar.get()
trio_test_contextvar.set("worker")
thread_current_value = trio_test_contextvar.get()
with pytest.raises(sniffio.AsyncLibraryNotFoundError):
sniffio.current_async_library()
async def async_back_in_main() -> tuple[str, str]:
back_parent_value = trio_test_contextvar.get()
trio_test_contextvar.set("back_in_main")
back_current_value = trio_test_contextvar.get()
assert sniffio.current_async_library() == "trio"
return back_parent_value, back_current_value
back_parent_value, back_current_value = from_thread_run(async_back_in_main)
thread_after_value = trio_test_contextvar.get()
with pytest.raises(sniffio.AsyncLibraryNotFoundError):
sniffio.current_async_library()
return (
thread_parent_value,
thread_current_value,
thread_after_value,
back_parent_value,
back_current_value,
)
(
thread_parent_value,
thread_current_value,
thread_after_value,
back_parent_value,
back_current_value,
) = await to_thread_run_sync(thread_fn)
current_value = trio_test_contextvar.get()
assert current_value == thread_parent_value == "main"
assert thread_current_value == back_parent_value == thread_after_value == "worker"
assert back_current_value == "back_in_main"
assert sniffio.current_async_library() == "trio"
def test_run_fn_as_system_task_catched_badly_typed_token() -> None:
with pytest.raises(RuntimeError):
from_thread_run_sync(
_core.current_time,
trio_token="Not TrioTokentype", # type: ignore[arg-type]
)
async def test_from_thread_inside_trio_thread() -> None:
def not_called() -> None: # pragma: no cover
raise AssertionError()
trio_token = _core.current_trio_token()
with pytest.raises(RuntimeError):
from_thread_run_sync(not_called, trio_token=trio_token)
def test_from_thread_run_during_shutdown() -> None:
save = []
record = []
async def agen(token: _core.TrioToken | None) -> AsyncGenerator[None, None]:
try:
yield
finally:
with _core.CancelScope(shield=True):
try:
await to_thread_run_sync(
partial(from_thread_run, sleep, 0, trio_token=token),
)
except _core.RunFinishedError:
record.append("finished")
else:
record.append("clean")
async def main(use_system_task: bool) -> None:
save.append(agen(_core.current_trio_token() if use_system_task else None))
await save[-1].asend(None)
_core.run(main, True) # System nursery will be closed and raise RunFinishedError
_core.run(main, False) # host task will be rescheduled as normal
assert record == ["finished", "clean"]
async def test_trio_token_weak_referenceable() -> None:
token = _core.current_trio_token()
assert isinstance(token, _core.TrioToken)
weak_reference = weakref.ref(token)
assert token is weak_reference()
async def test_unsafe_abandon_on_cancel_kwarg() -> None:
# This is a stand in for a numpy ndarray or other objects
# that (maybe surprisingly) lack a notion of truthiness
class BadBool:
def __bool__(self) -> bool:
raise NotImplementedError
with pytest.raises(NotImplementedError):
await to_thread_run_sync(int, abandon_on_cancel=BadBool()) # type: ignore[arg-type]
async def test_from_thread_reuses_task() -> None:
task = _core.current_task()
async def async_current_task() -> _core.Task:
return _core.current_task()
assert task is await to_thread_run_sync(from_thread_run_sync, _core.current_task)
assert task is await to_thread_run_sync(from_thread_run, async_current_task)
async def test_recursive_to_thread() -> None:
tid = None
def get_tid_then_reenter() -> int:
nonlocal tid
tid = threading.get_ident()
# The nesting of wrapper functions loses the return value of threading.get_ident
return from_thread_run(to_thread_run_sync, threading.get_ident) # type: ignore[no-any-return]
assert tid != await to_thread_run_sync(get_tid_then_reenter)
async def test_from_thread_host_cancelled() -> None:
queue: stdlib_queue.Queue[bool] = stdlib_queue.Queue()
def sync_check() -> None:
from_thread_run_sync(cancel_scope.cancel)
try:
from_thread_run_sync(bool)
except _core.Cancelled: # pragma: no cover
queue.put(True) # sync functions don't raise Cancelled
else:
queue.put(False)
with _core.CancelScope() as cancel_scope:
await to_thread_run_sync(sync_check)
assert not cancel_scope.cancelled_caught
assert not queue.get_nowait()
with _core.CancelScope() as cancel_scope:
await to_thread_run_sync(sync_check, abandon_on_cancel=True)
assert cancel_scope.cancelled_caught
assert not await to_thread_run_sync(partial(queue.get, timeout=1))
async def no_checkpoint() -> bool:
return True
def async_check() -> None:
from_thread_run_sync(cancel_scope.cancel)
try:
assert from_thread_run(no_checkpoint)
except _core.Cancelled: # pragma: no cover
queue.put(True) # async functions raise Cancelled at checkpoints
else:
queue.put(False)
with _core.CancelScope() as cancel_scope:
await to_thread_run_sync(async_check)
assert not cancel_scope.cancelled_caught
assert not queue.get_nowait()
with _core.CancelScope() as cancel_scope:
await to_thread_run_sync(async_check, abandon_on_cancel=True)
assert cancel_scope.cancelled_caught
assert not await to_thread_run_sync(partial(queue.get, timeout=1))
async def async_time_bomb() -> None:
cancel_scope.cancel()
with fail_after(10):
await sleep_forever()
with _core.CancelScope() as cancel_scope:
await to_thread_run_sync(from_thread_run, async_time_bomb)
assert cancel_scope.cancelled_caught
async def test_from_thread_check_cancelled() -> None:
q: stdlib_queue.Queue[str] = stdlib_queue.Queue()
async def child(abandon_on_cancel: bool, scope: CancelScope) -> None:
with scope:
record.append("start")
try:
return await to_thread_run_sync(f, abandon_on_cancel=abandon_on_cancel)
except _core.Cancelled:
record.append("cancel")
raise
finally:
record.append("exit")
def f() -> None:
try:
from_thread_check_cancelled()
except _core.Cancelled: # pragma: no cover, test failure path
q.put("Cancelled")
else:
q.put("Not Cancelled")
ev.wait()
return from_thread_check_cancelled()
# Base case: nothing cancelled so we shouldn't see cancels anywhere
record: list[str] = []
ev = threading.Event()
async with _core.open_nursery() as nursery:
nursery.start_soon(child, False, _core.CancelScope())
await wait_all_tasks_blocked()
assert record[0] == "start"
assert q.get(timeout=1) == "Not Cancelled"
ev.set()
# implicit assertion, Cancelled not raised via nursery
assert record[1] == "exit"
# abandon_on_cancel=False case: a cancel will pop out but be handled by
# the appropriate cancel scope
record = []
ev = threading.Event()
scope = _core.CancelScope() # Nursery cancel scope gives false positives
async with _core.open_nursery() as nursery:
nursery.start_soon(child, False, scope)
await wait_all_tasks_blocked()
assert record[0] == "start"
assert q.get(timeout=1) == "Not Cancelled"
scope.cancel()
ev.set()
assert scope.cancelled_caught
assert "cancel" in record
assert record[-1] == "exit"
# abandon_on_cancel=True case: slightly different thread behavior needed
# check thread is cancelled "soon" after abandonment
def f() -> None: # type: ignore[no-redef] # noqa: F811
ev.wait()
try:
from_thread_check_cancelled()
except _core.Cancelled:
q.put("Cancelled")
else: # pragma: no cover, test failure path
q.put("Not Cancelled")
record = []
ev = threading.Event()
scope = _core.CancelScope()
async with _core.open_nursery() as nursery:
nursery.start_soon(child, True, scope)
await wait_all_tasks_blocked()
assert record[0] == "start"
scope.cancel()
ev.set()
assert scope.cancelled_caught
assert "cancel" in record
assert record[-1] == "exit"
assert q.get(timeout=1) == "Cancelled"
async def test_from_thread_check_cancelled_raises_in_foreign_threads() -> None:
with pytest.raises(RuntimeError):
from_thread_check_cancelled()
q: stdlib_queue.Queue[Outcome[object]] = stdlib_queue.Queue()
_core.start_thread_soon(from_thread_check_cancelled, lambda _: q.put(_))
with pytest.raises(RuntimeError):
q.get(timeout=1).unwrap()
@slow
async def test_reentry_doesnt_deadlock() -> None:
# Regression test for issue noticed in GH-2827
# The failure mode is to hang the whole test suite, unfortunately.
# XXX consider running this in a subprocess with a timeout, if it comes up again!
async def child() -> None:
while True:
await to_thread_run_sync(from_thread_run, sleep, 0, abandon_on_cancel=False)
with move_on_after(2):
async with _core.open_nursery() as nursery:
for _ in range(4):
nursery.start_soon(child)
async def test_wait_all_threads_completed() -> None:
no_threads_left = False
e1 = Event()
e2 = Event()
e1_exited = Event()
e2_exited = Event()
async def wait_event(e: Event, e_exit: Event) -> None:
def thread() -> None:
from_thread_run(e.wait)
await to_thread_run_sync(thread)
e_exit.set()
async def wait_no_threads_left() -> None:
nonlocal no_threads_left
await wait_all_threads_completed()
no_threads_left = True
async with _core.open_nursery() as nursery:
nursery.start_soon(wait_event, e1, e1_exited)
nursery.start_soon(wait_event, e2, e2_exited)
await wait_all_tasks_blocked()
nursery.start_soon(wait_no_threads_left)
await wait_all_tasks_blocked()
assert not no_threads_left
assert active_thread_count() == 2
e1.set()
await e1_exited.wait()
await wait_all_tasks_blocked()
assert not no_threads_left
assert active_thread_count() == 1
e2.set()
await e2_exited.wait()
await wait_all_tasks_blocked()
assert no_threads_left
assert active_thread_count() == 0
async def test_wait_all_threads_completed_no_threads() -> None:
await wait_all_threads_completed()
assert active_thread_count() == 0