Always raise asyncio errors

If the root calls `trio.Process.kill()` on immediate child proc teardown
when the child is using pdb, we can get stdstreams clobbering that
results in a pdb++ repl where the user can't see what's been typed. Not
killing such children on cancellation / error seems to resolve this
issue whilst still giving reliable termination. For now, code that
special path until a time it becomes a problem for ensuring zombie
reaps.

tractor/_debug.py

@@ -254,6 +254,7 @@ async def _hijack_stdin_for_child(
                 #     assert await stream.receive() == 'pdb_unlock'
 
         except (
+            trio.MultiError,
             trio.BrokenResourceError,
             trio.Cancelled,  # by local cancellation
             trio.ClosedResourceError,  # by self._rx_chan
@@ -343,6 +344,7 @@ async def _breakpoint(
 
             except tractor.ContextCancelled:
                 log.warning('Root actor cancelled debug lock')
+                raise
 
             finally:
                 log.debug(f"Exiting debugger for actor {actor}")
@@ -407,7 +409,11 @@ async def _breakpoint(
                 'Root actor attempting to shield-acquire active tty lock'
                 f' owned by {_global_actor_in_debug}')
 
-            with trio.CancelScope(shield=True):
+            stats = _debug_lock.statistics()
+            if stats.owner:
+                breakpoint()
+
+            # with trio.CancelScope(shield=True):
             # must shield here to avoid hitting a ``Cancelled`` and
             # a child getting stuck bc we clobbered the tty
             await _debug_lock.acquire()

tractor/_root.py

@@ -238,7 +238,7 @@ def run(
 
 
 def run_daemon(
-    rpc_module_paths: List[str],
+    enable_modules: List[str],
     **kwargs
 ) -> None:
     """Spawn daemon actor which will respond to RPC.
@@ -247,9 +247,9 @@ def run_daemon(
     ``tractor.run(trio.sleep(float('inf')))`` such that the first actor spawned
     is meant to run forever responding to RPC requests.
     """
-    kwargs['rpc_module_paths'] = list(rpc_module_paths)
+    kwargs['enable_modules'] = list(enable_modules)
 
-    for path in rpc_module_paths:
+    for path in enable_modules:
         importlib.import_module(path)
 
     return run(partial(trio.sleep, float('inf')), **kwargs)

tractor/_spawn.py

@@ -331,6 +331,7 @@ async def new_proc(
             bind_addr=bind_addr,
             parent_addr=parent_addr,
             _runtime_vars=_runtime_vars,
+            infect_asyncio=infect_asyncio,
             task_status=task_status,
         )
 
@@ -346,6 +347,7 @@ async def mp_new_proc(
     parent_addr: Tuple[str, int],
     _runtime_vars: Dict[str, Any],  # serialized and sent to _child
     *,
+    infect_asyncio: bool = False,
     task_status: TaskStatus[Portal] = trio.TASK_STATUS_IGNORED
 
 ) -> None:

tractor/to_asyncio.py

@@ -1,6 +1,7 @@
-"""
+'''
 Infection apis for ``asyncio`` loops running ``trio`` using guest mode.
-"""
+
+'''
 import asyncio
 import inspect
 from typing import (
@@ -43,15 +44,16 @@ async def consume_asyncgen(
         to_trio.send_nowait(item)
 
 
-async def run_task(
+def _run_asyncio_task(
     func: Callable,
     *,
-    qsize: int = 2**10,
+    qsize: int = 1,
     _treat_as_stream: bool = False,
     **kwargs,
 ) -> Any:
     """Run an ``asyncio`` async function or generator in a task, return
     or stream the result back to ``trio``.
+
     """
     assert current_actor().is_infected_aio()
 
@@ -59,20 +61,27 @@ async def run_task(
     from_trio = asyncio.Queue(qsize)  # type: ignore
     to_trio, from_aio = trio.open_memory_channel(qsize)  # type: ignore
 
+    from_aio._err = None
+
     args = tuple(inspect.getfullargspec(func).args)
 
     if getattr(func, '_tractor_steam_function', None):
         # the assumption is that the target async routine accepts the
         # send channel then it intends to yield more then one return
         # value otherwise it would just return ;P
-        _treat_as_stream = True
+        # _treat_as_stream = True
+        assert qsize > 1
 
     # allow target func to accept/stream results manually by name
     if 'to_trio' in args:
         kwargs['to_trio'] = to_trio
+
     if 'from_trio' in args:
         kwargs['from_trio'] = from_trio
 
+    # if 'from_aio' in args:
+    #     kwargs['from_aio'] = from_aio
+
     coro = func(**kwargs)
 
     cancel_scope = trio.CancelScope()
@@ -80,8 +89,10 @@ async def run_task(
     # start the asyncio task we submitted from trio
     if inspect.isawaitable(coro):
         task = asyncio.create_task(run_coro(to_trio, coro))
+
     elif inspect.isasyncgen(coro):
         task = asyncio.create_task(consume_asyncgen(to_trio, coro))
+
     else:
         raise TypeError(f"No support for invoking {coro}")
 
@@ -91,59 +102,93 @@ async def run_task(
         """Cancel the calling ``trio`` task on error.
         """
         nonlocal aio_err
+        try:
             aio_err = task.exception()
+        except asyncio.CancelledError as cerr:
+            aio_err = cerr
 
         if aio_err:
             log.exception(f"asyncio task errorred:\n{aio_err}")
 
         cancel_scope.cancel()
+        from_aio._err = aio_err
+        from_aio.close()
 
     task.add_done_callback(cancel_trio)
 
-    # async iterator
-    if inspect.isasyncgen(coro) or _treat_as_stream:
+    return task, from_aio, to_trio, cancel_scope
 
-        async def stream_results():
-            try:
-                with cancel_scope:
-                    # stream values upward
-                    async with from_aio:
-                        async for item in from_aio:
-                            yield item
 
-                if cancel_scope.cancelled_caught:
-                    # always raise from any captured asyncio error
-                    if aio_err:
-                        raise aio_err
+async def run_task(
 
-            except BaseException as err:
-                if aio_err is not None:
-                    # always raise from any captured asyncio error
-                    raise err from aio_err
-                else:
-                    raise
+    func: Callable,
+    *,
 
-        return stream_results()
+    qsize: int = 2**10,
+    _treat_as_stream: bool = False,
+    **kwargs,
+
+) -> Any:
+    """Run an ``asyncio`` async function or generator in a task, return
+    or stream the result back to ``trio``.
+
+    """
+    # streaming ``asyncio`` task
+    if _treat_as_stream:
+
+        task, from_aio, to_trio, cs = _run_asyncio_task(
+            func,
+            qsize=2**8,
+            **kwargs,
+        )
+
+        # naively expect the mem chan api to do the job
+        # of handling cross-framework cancellations / errors
+        return from_aio
 
     # simple async func
     try:
-        with cancel_scope:
+        task, from_aio, to_trio, cs = _run_asyncio_task(
+            func,
+            qsize=1,
+            **kwargs,
+        )
+
         # return single value
+        with cs:
             return await from_aio.receive()
 
-        if cancel_scope.cancelled_caught:
-            # always raise from any captured asyncio error
-            if aio_err:
-                raise aio_err
-
-    # Do we need this?
-    except BaseException as err:
-        if aio_err is not None:
-            # always raise from any captured asyncio error
-            raise err from aio_err
-        else:
+    except trio.Cancelled:
+        if not task.done():
+            task.cancel()
         raise
 
+    finally:
+        if from_aio._err:
+            raise from_aio._err
+
+
+# TODO: explicit api for the streaming case where
+# we pull from the mem chan in an async generator?
+# This ends up looking more like our ``Portal.open_stream_from()``
+# NB: code below is untested.
+
+# @asynccontextmanager
+# async def stream_from_task(
+
+#     target: Callable[Any],
+#     **kwargs,
+
+# ) -> AsyncIterator[Any]:
+
+#     from_aoi = await run_task(target, _treat_as_stream=True, **kwargs)
+
+#     with cancel_scope:
+#         # stream values upward
+#         async with from_aio:
+#             async for item in from_aio:
+#                 yield item
+
 
 def run_as_asyncio_guest(
     trio_main: Callable,