Merge pull request #92 from goodboy/drop_event_clear

Drop use of `trio.Event.clear()`

tests/test_cancellation.py

@@ -261,13 +261,26 @@ async def test_some_cancels_all(num_actors_and_errs, start_method):
         pytest.fail("Should have gotten a remote assertion error?")
 
 
-async def spawn_and_error(num) -> None:
+async def spawn_and_error(breadth, depth) -> None:
     name = tractor.current_actor().name
     async with tractor.open_nursery() as nursery:
-        for i in range(num):
-            await nursery.run_in_actor(
-                f'{name}_errorer_{i}', assert_err
+        for i in range(breadth):
+            if depth > 0:
+                args = (
+                    f'spawner_{i}_depth_{depth}',
+                    spawn_and_error,
                 )
+                kwargs = {
+                    'breadth': breadth,
+                    'depth': depth - 1,
+                }
+            else:
+                args = (
+                    f'{name}_errorer_{i}',
+                    assert_err,
+                )
+                kwargs = {}
+            await nursery.run_in_actor(*args, **kwargs)
 
 
 @tractor_test
@@ -276,25 +289,34 @@ async def test_nested_multierrors(loglevel, start_method):
     This test goes only 2 nurseries deep but we should eventually have tests
     for arbitrary n-depth actor trees.
     """
-    if platform.system() == 'Windows':
-        # Windows CI seems to be partifcularly fragile on Python 3.8..
-        num_subactors = 2
-    else:
-        # XXX: any more then this and the forkserver will
-        # start bailing hard...gotta look into it
-        num_subactors = 4
+    # XXX: forkserver can't seem to handle any more then 2 depth
+    # process trees for whatever reason.
+    # Any more process levels then this and we start getting pretty slow anyway
+    depth = 3
+    subactor_breadth = 2
 
+    with trio.fail_after(120):
         try:
             async with tractor.open_nursery() as nursery:
-
-            for i in range(num_subactors):
+                for i in range(subactor_breadth):
                     await nursery.run_in_actor(
                         f'spawner_{i}',
                         spawn_and_error,
-                    num=num_subactors,
+                        breadth=subactor_breadth,
+                        depth=depth,
                     )
         except trio.MultiError as err:
-        assert len(err.exceptions) == num_subactors
+            assert len(err.exceptions) == subactor_breadth
             for subexc in err.exceptions:
                 assert isinstance(subexc, tractor.RemoteActorError)
+                if depth > 1 and subactor_breadth > 1:
+
+                    # XXX not sure what's up with this..
+                    if platform.system() == 'Windows':
+                        assert (subexc.type is trio.MultiError) or (
+                            subexc.type is tractor.RemoteActorError)
+                    else:
                         assert subexc.type is trio.MultiError
+                else:
+                    assert (subexc.type is tractor.RemoteActorError) or (
+                        subexc.type is trio.Cancelled)

tractor/_actor.py

@@ -144,7 +144,7 @@ async def _invoke(
 
         if not actor._rpc_tasks:
             log.info(f"All RPC tasks have completed")
-            actor._no_more_rpc_tasks.set()
+            actor._ongoing_rpc_tasks.set()
 
 
 class Actor:
@@ -183,9 +183,8 @@ class Actor:
         self._peer_connected: dict = {}
         self._no_more_peers = trio.Event()
         self._no_more_peers.set()
-
-        self._no_more_rpc_tasks = trio.Event()
-        self._no_more_rpc_tasks.set()
+        self._ongoing_rpc_tasks = trio.Event()
+        self._ongoing_rpc_tasks.set()
         # (chan, cid) -> (cancel_scope, func)
         self._rpc_tasks: Dict[
             Tuple[Channel, str],
@@ -234,7 +233,7 @@ class Actor:
     ) -> None:
         """Entry point for new inbound connections to the channel server.
         """
-        self._no_more_peers.clear()
+        self._no_more_peers = trio.Event()
         chan = Channel(stream=stream)
         log.info(f"New connection to us {chan}")
 
@@ -448,7 +447,7 @@ class Actor:
                                      f"{cs}")
                         else:
                             # mark that we have ongoing rpc tasks
-                            self._no_more_rpc_tasks.clear()
+                            self._ongoing_rpc_tasks = trio.Event()
                             log.info(f"RPC func is {func}")
                             # store cancel scope such that the rpc task can be
                             # cancelled gracefully if requested
@@ -709,10 +708,9 @@ class Actor:
         for (chan, cid) in tasks.copy():
             # TODO: this should really done in a nursery batch
             await self._cancel_task(cid, chan)
-        # if tasks:
         log.info(
             f"Waiting for remaining rpc tasks to complete {tasks}")
-        await self._no_more_rpc_tasks.wait()
+        await self._ongoing_rpc_tasks.wait()
 
     def cancel_server(self) -> None:
         """Cancel the internal channel server nursery thereby