signal: Finally clean up all leaks after complete understanding

The PYSIDE-79 bug was never understood, completely.
After getting much more clarity through the work on
PYSIDE-2201, the real problem could be found:

It turned out that the implementation of descriptors was
incomplete. Instead of respecting an already cached instance,
it created a new one, all the time, resulting in a serious leak!

This became visible by deep inspection of the control flow
with VS-Code. After the interaction of PyObject_GetAttr,
getHiddenDataFromQObject and signalDescrGet became transparent,
the function was completed and the issue finally solved.

Fixes: PYSIDE-79
Task-number: PYSIDE-68
Task-number: PYSIDE-2201
Change-Id: Ifd6098b1ce43d9bf51350218deb031bbf9ccb97a
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 1 insertions, 9 deletions

diff --git a/sources/pyside6/libpyside/pyside.cpp b/sources/pyside6/libpyside/pyside.cpp
index a60b7131a..aa6dcc9a9 100644
--- a/sources/pyside6/libpyside/pyside.cpp
+++ b/sources/pyside6/libpyside/pyside.cpp
@@ -494,6 +494,7 @@ PyObject *getHiddenDataFromQObject(QObject *cppSelf, PyObject *self, PyObject *n
 {
     using Shiboken::AutoDecRef;
 
+    // PYSIDE-68-bis: This getattr finds signals early by `signalDescrGet`.
     PyObject *attr = PyObject_GenericGetAttr(self, name);
     if (!Shiboken::Object::isValid(reinterpret_cast<SbkObject *>(self), false))
         return attr;
@@ -506,15 +507,6 @@ PyObject *getHiddenDataFromQObject(QObject *cppSelf, PyObject *self, PyObject *n
         attr = value;
     }
 
-    // Mutate native signals to signal instance type
-    // Caution: This inserts the signal instance into the instance dict.
-    if (attr && PyObject_TypeCheck(attr, PySideSignal_TypeF())) {
-        auto *inst = Signal::initialize(reinterpret_cast<PySideSignal *>(attr), name, self);
-        PyObject *signalInst = reinterpret_cast<PyObject *>(inst);
-        PyObject_SetAttr(self, name, signalInst);
-        return signalInst;
-    }
-
     // Search on metaobject (avoid internal attributes started with '__')
     if (!attr) {
         PyObject *type, *value, *traceback;