QtAsyncio: Improve handling of outside termination

Improve how QtAsyncio handles when the QCoreApplication is quit from
outside, e.g., when pressing the close button. This will prevent
scenarios where asyncio runs the BaseEventLoop destructor after the Qt
application had already been shut down, resulting in RuntimeError. In
addition, this removes some unnecessary RuntimeError raises related to
a closed event loop.

Pick-to: 6.6
Task-number: PYSIDE-769
Change-Id: I52553eed271b5fb5790c09751dd58cc2e52fa174
Reviewed-by: Shyamnath Premnadh <Shyamnath.Premnadh@qt.io>

1 files changed, 5 insertions, 8 deletions

diff --git a/sources/pyside6/PySide6/QtAsyncio/events.py b/sources/pyside6/PySide6/QtAsyncio/events.py
index bd58d7dba..cec26ee72 100644
--- a/sources/pyside6/PySide6/QtAsyncio/events.py
+++ b/sources/pyside6/PySide6/QtAsyncio/events.py
@@ -76,7 +76,7 @@ class QAsyncioEventLoopPolicy(asyncio.AbstractEventLoopPolicy):
 
     def get_event_loop(self) -> asyncio.AbstractEventLoop:
         if self._event_loop is None:
-            self._event_loop = QAsyncioEventLoop(self._application)
+            self._event_loop = QAsyncioEventLoop(self._application, quit_qapp=self._quit_qapp)
         return self._event_loop
 
     def set_event_loop(self, loop: typing.Optional[asyncio.AbstractEventLoop]) -> None:
@@ -190,6 +190,7 @@ class QAsyncioEventLoop(asyncio.BaseEventLoop, QObject):
     def _about_to_quit_cb(self):
         if not self._quit_from_inside:
             self._quit_from_outside = True
+            self.close()
 
     def stop(self) -> None:
         if self._future_to_complete is not None:
@@ -208,14 +209,12 @@ class QAsyncioEventLoop(asyncio.BaseEventLoop, QObject):
         return self._closed
 
     def close(self) -> None:
-        if self.is_running():
+        if self.is_running() and not self._quit_from_outside:
             raise RuntimeError("Cannot close a running event loop")
         if self.is_closed():
             return
         if self._default_executor is not None:
             self._default_executor.shutdown(wait=False)
-        if self._quit_qapp:
-            self._application.shutdown()
         self._closed = True
 
     async def shutdown_asyncgens(self) -> None:
@@ -275,6 +274,8 @@ class QAsyncioEventLoop(asyncio.BaseEventLoop, QObject):
     def call_soon_threadsafe(self, callback: typing.Callable, *args: typing.Any,
                              context:
                              typing.Optional[contextvars.Context] = None) -> asyncio.Handle:
+        if self.is_closed():
+            raise RuntimeError("Event loop is closed")
         if context is None:
             context = contextvars.copy_context()
         return self._call_soon_impl(callback, *args, context=context, is_threadsafe=True)
@@ -299,8 +300,6 @@ class QAsyncioEventLoop(asyncio.BaseEventLoop, QObject):
                       is_threadsafe: typing.Optional[bool] = False) -> asyncio.TimerHandle:
         if not isinstance(when, (int, float)):
             raise TypeError("when must be an int or float")
-        if self.is_closed():
-            raise RuntimeError("Event loop is closed")
         return QAsyncioTimerHandle(when, callback, args, self, context, is_threadsafe=is_threadsafe)
 
     def call_at(self, when: typing.Union[int, float],
@@ -320,8 +319,6 @@ class QAsyncioEventLoop(asyncio.BaseEventLoop, QObject):
                     coro: typing.Union[collections.abc.Generator, collections.abc.Coroutine],
                     *, name: typing.Optional[str] = None,
                     context: typing.Optional[contextvars.Context] = None) -> tasks.QAsyncioTask:
-        if self.is_closed():
-            raise RuntimeError("Event loop is closed")
         if self._task_factory is None:
             task = tasks.QAsyncioTask(coro, loop=self, name=name, context=context)
         else: