avoid calls to make_current() and make_clear() by using asyncio.run in LoopRunner

distributed/actor.py

@@ -1,9 +1,7 @@
 from __future__ import annotations
 
 import abc
-import asyncio
 import functools
-import sys
 import threading
 from collections.abc import Awaitable, Generator
 from dataclasses import dataclass
@@ -14,41 +12,13 @@
 
 from distributed.client import Future
 from distributed.protocol import to_serialize
-from distributed.utils import iscoroutinefunction, sync, thread_state
+from distributed.utils import LateLoopEvent, iscoroutinefunction, sync, thread_state
 from distributed.utils_comm import WrappedKey
 from distributed.worker import get_client, get_worker
 
 _T = TypeVar("_T")
 
 
-if sys.version_info >= (3, 10):
-    from asyncio import Event as _LateLoopEvent
-else:
-    # In python 3.10 asyncio.Lock and other primitives no longer support
-    # passing a loop kwarg to bind to a loop running in another thread
-    # e.g. calling from Client(asynchronous=False). Instead the loop is bound
-    # as late as possible: when calling any methods that wait on or wake
-    # Future instances. See: https://bugs.python.org/issue42392
-    class _LateLoopEvent:
-        def __init__(self) -> None:
-            self._event: asyncio.Event | None = None
-
-        def set(self) -> None:
-            if self._event is None:
-                self._event = asyncio.Event()
-
-            self._event.set()
-
-        def is_set(self) -> bool:
-            return self._event is not None and self._event.is_set()
-
-        async def wait(self) -> bool:
-            if self._event is None:
-                self._event = asyncio.Event()
-
-            return await self._event.wait()
-
-
 class Actor(WrappedKey):
     """Controls an object on a remote worker
 
@@ -322,7 +292,7 @@ def unwrap(self) -> NoReturn:
 class ActorFuture(BaseActorFuture[_T]):
     def __init__(self, io_loop: IOLoop):
         self._io_loop = io_loop
-        self._event = _LateLoopEvent()
+        self._event = LateLoopEvent()
         self._out: _Error | _OK[_T] | None = None
 
     def __await__(self) -> Generator[object, None, _T]:

distributed/deploy/cluster.py

@@ -206,16 +206,17 @@ async def _close(self):
 
         self.status = Status.closed
 
-    def close(self, timeout=None):
+    def close(self, timeout: float | None = None) -> Any:
         # If the cluster is already closed, we're already done
         if self.status == Status.closed:
             if self.asynchronous:
                 return NoOpAwaitable()
-            else:
-                return
+            return None
 
-        with suppress(RuntimeError):  # loop closed during process shutdown
+        try:
             return self.sync(self._close, callback_timeout=timeout)
+        except RuntimeError:  # loop closed during process shutdown
+            return None
 
     def __del__(self, _warn=warnings.warn):
         if getattr(self, "status", Status.closed) != Status.closed:
@@ -519,10 +520,16 @@ def _ipython_display_(self, **kwargs):
             display(mimebundle, raw=True)
 
     def __enter__(self):
+        if self.asynchronous:
+            raise TypeError(
+                "Used 'with' with asynchronous class; please use 'async with'"
+            )
+
         return self.sync(self.__aenter__)
 
     def __exit__(self, exc_type, exc_value, traceback):
-        return self.sync(self.__aexit__, exc_type, exc_value, traceback)
+        aw = self.close()
+        assert aw is None, aw
 
     def __await__(self):
         return self

distributed/deploy/spec.py

@@ -293,8 +293,15 @@ def __init__(
                 self.sync(self._correct_state)
             except Exception:
                 self.sync(self.close)
+                self._loop_runner.stop()
                 raise
 
+    def close(self, timeout: float | None = None) -> Awaitable[None] | None:
+        aw = super().close(timeout)
+        if not self.asynchronous:
+            self._loop_runner.stop()
+        return aw
+
     async def _start(self):
         while self.status == Status.starting:
             await asyncio.sleep(0.01)
@@ -472,10 +479,6 @@ async def __aenter__(self):
         assert self.status == Status.running
         return self
 
-    def __exit__(self, exc_type, exc_value, traceback):
-        super().__exit__(exc_type, exc_value, traceback)
-        self._loop_runner.stop()
-
     def _threads_per_worker(self) -> int:
         """Return the number of threads per worker for new workers"""
         if not self.new_spec:  # pragma: no cover

distributed/deploy/tests/test_adaptive.py

@@ -279,8 +279,6 @@ async def test_no_more_workers_than_tasks():
                 assert len(cluster.scheduler.workers) <= 1
 
 
-@pytest.mark.filterwarnings("ignore:There is no current event loop:DeprecationWarning")
-@pytest.mark.filterwarnings("ignore:make_current is deprecated:DeprecationWarning")
 def test_basic_no_loop(cleanup):
     loop = None
     try:
@@ -293,8 +291,7 @@ def test_basic_no_loop(cleanup):
                 assert future.result() == 2
             loop = cluster.loop
     finally:
-        if loop is not None:
-            loop.add_callback(loop.stop)
+        assert loop is None or not loop.asyncio_loop.is_running()
 
 
 @pytest.mark.flaky(condition=LINUX, reruns=10, reruns_delay=5)

distributed/deploy/tests/test_cluster.py

@@ -77,3 +77,13 @@ def test_exponential_backoff():
     assert _exponential_backoff(5, 1.5, 3, 20) == 20
     # avoid overflow
     assert _exponential_backoff(1000, 1.5, 3, 20) == 20
+
+
+@gen_test()
+async def test_sync_context_manager_used_with_async_cluster():
+    async with Cluster(asynchronous=True, name="A") as cluster:
+        with pytest.raises(
+            TypeError,
+            match=r"Used 'with' with asynchronous class; please use 'async with'",
+        ), cluster:
+            pass

distributed/deploy/tests/test_spec_cluster.py

@@ -82,8 +82,6 @@ def test_spec_sync(loop):
             assert result == 11
 
 
-@pytest.mark.filterwarnings("ignore:There is no current event loop:DeprecationWarning")
-@pytest.mark.filterwarnings("ignore:make_current is deprecated:DeprecationWarning")
 def test_loop_started_in_constructor(cleanup):
     # test that SpecCluster.__init__ starts a loop in another thread
     cluster = SpecCluster(worker_spec, scheduler=scheduler, loop=None)

distributed/tests/test_actor.py

@@ -19,8 +19,8 @@
     wait,
     worker_client,
 )
-from distributed.actor import _LateLoopEvent
 from distributed.metrics import time
+from distributed.utils import LateLoopEvent
 from distributed.utils_test import cluster, double, gen_cluster, inc
 from distributed.worker import get_worker
 
@@ -263,7 +263,7 @@ def test_sync(client):
 def test_timeout(client):
     class Waiter:
         def __init__(self):
-            self.event = _LateLoopEvent()
+            self.event = LateLoopEvent()
 
         async def set(self):
             self.event.set()
@@ -555,7 +555,7 @@ def sleep(self, time):
 async def test_waiter(c, s, a, b):
     class Waiter:
         def __init__(self):
-            self.event = _LateLoopEvent()
+            self.event = LateLoopEvent()
 
         async def set(self):
             self.event.set()

distributed/tests/test_client.py

@@ -84,14 +84,7 @@
 from distributed.scheduler import CollectTaskMetaDataPlugin, KilledWorker, Scheduler
 from distributed.shuffle import check_minimal_arrow_version
 from distributed.sizeof import sizeof
-from distributed.utils import (
-    NoOpAwaitable,
-    get_mp_context,
-    is_valid_xml,
-    open_port,
-    sync,
-    tmp_text,
-)
+from distributed.utils import get_mp_context, is_valid_xml, open_port, sync, tmp_text
 from distributed.utils_test import (
     NO_AMM,
     BlockedGatherDep,
@@ -2106,27 +2099,8 @@ async def test_multi_client(s, a, b):
         await asyncio.sleep(0.01)
 
 
-@contextmanager
-def _pristine_loop():
-    IOLoop.clear_instance()
-    IOLoop.clear_current()
-    loop = IOLoop()
-    loop.make_current()
-    assert IOLoop.current() is loop
-    try:
-        yield loop
-    finally:
-        try:
-            loop.close(all_fds=True)
-        except (KeyError, ValueError):
-            pass
-        IOLoop.clear_instance()
-        IOLoop.clear_current()
-
-
 def long_running_client_connection(address):
-    with _pristine_loop():
-        c = Client(address)
+    with Client(address, loop=None) as c:
         x = c.submit(lambda x: x + 1, 10)
         x.result()
         sleep(100)
@@ -2779,8 +2753,6 @@ async def test_startup_close_startup(s, a, b):
         pass
 
 
-@pytest.mark.filterwarnings("ignore:There is no current event loop:DeprecationWarning")
-@pytest.mark.filterwarnings("ignore:make_current is deprecated:DeprecationWarning")
 def test_startup_close_startup_sync(loop):
     with cluster() as (s, [a, b]):
         with Client(s["address"], loop=loop) as c:
@@ -5652,23 +5624,12 @@ async def test_future_auto_inform(c, s, a, b):
             await asyncio.sleep(0.01)
 
 
-@pytest.mark.filterwarnings("ignore:There is no current event loop:DeprecationWarning")
-@pytest.mark.filterwarnings("ignore:make_current is deprecated:DeprecationWarning")
-@pytest.mark.filterwarnings("ignore:clear_current is deprecated:DeprecationWarning")
 def test_client_async_before_loop_starts(cleanup):
-    async def close():
-        async with client:
-            pass
-
-    with _pristine_loop() as loop:
-        with pytest.warns(
-            DeprecationWarning,
-            match=r"Constructing LoopRunner\(loop=loop\) without a running loop is deprecated",
-        ):
-            client = Client(asynchronous=True, loop=loop)
-        assert client.asynchronous
-        assert isinstance(client.close(), NoOpAwaitable)
-        loop.run_sync(close)  # TODO: client.close() does not unset global client
+    with pytest.raises(
+        RuntimeError,
+        match=r"Constructing LoopRunner\(asynchronous=True\) without a running loop is not supported",
+    ):
+        client = Client(asynchronous=True, loop=None)
 
 
 @pytest.mark.slow
@@ -7110,8 +7071,6 @@ async def test_workers_collection_restriction(c, s, a, b):
     assert a.data and not b.data
 
 
-@pytest.mark.filterwarnings("ignore:There is no current event loop:DeprecationWarning")
-@pytest.mark.filterwarnings("ignore:make_current is deprecated:DeprecationWarning")
 @gen_cluster(client=True, nthreads=[("127.0.0.1", 1)])
 async def test_get_client_functions_spawn_clusters(c, s, a):
     # see gh4565

distributed/tests/test_client_loop.py

@@ -2,8 +2,6 @@
 
 import contextlib
 
-import pytest
-
 from distributed import Client, LocalCluster
 from distributed.utils import LoopRunner
 
@@ -29,16 +27,12 @@ def _check_cluster_and_client_loop(loop):
 
 
 # Test if Client stops LoopRunner on close.
-@pytest.mark.filterwarnings("ignore:There is no current event loop:DeprecationWarning")
-@pytest.mark.filterwarnings("ignore:make_current is deprecated:DeprecationWarning")
 def test_close_loop_sync_start_new_loop(cleanup):
     with _check_loop_runner():
         _check_cluster_and_client_loop(loop=None)
 
 
 # Test if Client stops LoopRunner on close.
-@pytest.mark.filterwarnings("ignore:There is no current event loop:DeprecationWarning")
-@pytest.mark.filterwarnings("ignore:make_current is deprecated:DeprecationWarning")
 def test_close_loop_sync_use_running_loop(cleanup):
     with _check_loop_runner():
         # Start own loop or use current thread's one.