allow to use shiboken.delete() to delete Q*Application

This function should initially not allow deleting Q*Application
with a shiboken.delete() function, but unfortunately some
competitor can do that, so we will as well.

Deletion of qApp needs knowledge about qApp.
We add a hook function that calls the pyside function
  `destroyQCoreApplication`.

A special problem was testing interactively.
See the error description for the days long journey :)

Change-Id: I34862425c2cb2cc80d6cafc22d25a867f96f3e0a
Fixes: PYSIDE-1470
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>
(cherry picked from commit 98aba46414b666c27df3904d2b4313f0a16e05dc)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/sources/pyside6/libpyside/pyside.cpp b/sources/pyside6/libpyside/pyside.cpp
index 75b3eb16f..22230703e 100644
--- a/sources/pyside6/libpyside/pyside.cpp
+++ b/sources/pyside6/libpyside/pyside.cpp
@@ -308,6 +308,9 @@ void initQApp()
      */
     if (!qApp)
         Py_DECREF(MakeQAppWrapper(nullptr));
+
+    // PYSIDE-1470: Register a function to destroy an application from shiboken.
+    setDestroyQApplication(destroyQCoreApplication);
 }
 
 PyObject *getMetaDataFromQObject(QObject *cppSelf, PyObject *self, PyObject *name)