Fix crash of signals with object-type parameter being passed by const-ref

Add a further indirection in callPythonMetaMethodHelper()
when only a pointer conversion is available for a const-ref parameter.

Task-number: PYSIDE-3004
Change-Id: I6ec7c5a9d4d30c8e4973ec79534d5f3eb3bf8204
Reviewed-by: Shyamnath Premnadh <[email protected]>

4 files changed, 29 insertions, 3 deletions

diff --git a/sources/pyside6/libpyside/signalmanager.cpp b/sources/pyside6/libpyside/signalmanager.cpp
index 744b77b51..72a427641 100644
--- a/sources/pyside6/libpyside/signalmanager.cpp
+++ b/sources/pyside6/libpyside/signalmanager.cpp
@@ -464,16 +464,21 @@ static int callPythonMetaMethodHelper(const QByteArrayList &paramTypes,
                                       const char *returnType /* = nullptr */,
                                       void **args, PyObject *pyCallable)
 {
+    using SpecificConverter = Shiboken::Conversions::SpecificConverter;
     const qsizetype argsSize = paramTypes.size();
     Shiboken::AutoDecRef preparedArgs(PyTuple_New(argsSize));
 
     for (qsizetype i = 0; i < argsSize; ++i) {
         void *data = args[i + 1];
-        auto param = paramTypes.at(i);
-        Shiboken::Conversions::SpecificConverter converter(param.constData());
+        const auto &param = paramTypes.at(i);
+        SpecificConverter converter(param.constData());
         if (!converter.isValid())
             return CallResult::CallArgumentError + int(i);
-        PyTuple_SetItem(preparedArgs, i, converter.toPython(data));
+        // Only pointer conversion available for const-ref - add indirection
+        const bool valueToPtr = converter.conversionType() == SpecificConverter::PointerConversion
+            && !param.endsWith('*') && param != "PyObject"_ba;
+        auto *src = valueToPtr ? &data : data;
+        PyTuple_SetItem(preparedArgs, i, converter.toPython(src));
     }
 
     QScopedPointer<Shiboken::Conversions::SpecificConverter> retConverter;
diff --git a/sources/pyside6/tests/pysidetest/signalemissionfrompython_test.py b/sources/pyside6/tests/pysidetest/signalemissionfrompython_test.py
index 34b8f7f62..64147e15e 100644
--- a/sources/pyside6/tests/pysidetest/signalemissionfrompython_test.py
+++ b/sources/pyside6/tests/pysidetest/signalemissionfrompython_test.py
@@ -27,6 +27,11 @@ class Receiver(QObject):
     def __init__(self, p=None):
         super().__init__(p)
         self.received_handle = -1
+        self.received_name = ''
+
+    @Slot(QObject)
+    def slotObjectByConstRef(self, o):
+        self.received_name = o.objectName()
 
     @Slot(Connection)
     def connectionSlot(self, c):
@@ -37,7 +42,9 @@ class SignalEmissionFromPython(unittest.TestCase):
 
     def setUp(self):
         self.obj1 = TestObject(0)
+        self.obj1.setObjectName('obj1')
         self.obj2 = TestObject(0)
+        self.obj2.setObjectName('obj2')
         self.one_called = 0
         self.two_called = 0
 
@@ -114,6 +121,12 @@ class SignalEmissionFromPython(unittest.TestCase):
         self.assertEqual(self.one_called, 1)
         self.assertEqual(self.two_called, 2)
 
+    def testSignalObjectByConstRef(self):
+        receiver = Receiver()
+        self.obj1.objectByConstRef.connect(receiver.slotObjectByConstRef)
+        self.obj1.emitObjectByConstRef()
+        self.assertEqual(receiver.received_name, 'obj1')
+
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/sources/pyside6/tests/pysidetest/testobject.cpp b/sources/pyside6/tests/pysidetest/testobject.cpp
index bcf629bf8..3107be09a 100644
--- a/sources/pyside6/tests/pysidetest/testobject.cpp
+++ b/sources/pyside6/tests/pysidetest/testobject.cpp
@@ -47,6 +47,11 @@ void TestObject::emitFlagsSignal(Qt::Alignment alignment)
     emit flagsSignal(alignment);
 }
 
+void TestObject::emitObjectByConstRef()
+{
+    emit objectByConstRef(*this);
+}
+
 void TestObject::setQLatin1String(QLatin1String v)
 {
     m_qLatin1String = v;
diff --git a/sources/pyside6/tests/pysidetest/testobject.h b/sources/pyside6/tests/pysidetest/testobject.h
index 9689589ad..7c273c891 100644
--- a/sources/pyside6/tests/pysidetest/testobject.h
+++ b/sources/pyside6/tests/pysidetest/testobject.h
@@ -54,6 +54,8 @@ public:
 
     void emitFlagsSignal(Qt::Alignment alignment);
 
+    void emitObjectByConstRef();
+
     static constexpr auto LATIN1_TEST_FIELD = QLatin1StringView("test");
 
     void setQLatin1String(QLatin1String v);
@@ -69,6 +71,7 @@ signals:
     void signalWithTypedefValue(TypedefValue value);
     void signalWithContainerTypedefValue(const IntList &il);
     void flagsSignal(Qt::Alignment alignment);
+    void objectByConstRef(const QObject &qobject);
 
 private:
     int m_idValue;