moc/QMetaProperty: Remove limitation on non-own-class notify signals

The moc generated code does a sanity check that NOTIFY signals actually
exist in the parent class when they cannot be found in the class moc
currently runs on.
The logic there was however too simplistic, and couldn't deal with
signals taking a parameter.
Fix this, and take the opportunity to use a proper static_assert instead
of generating a "normal" compile error.

We do not do any checks for the presence of QPrivateSignal, as the whole
point of QPrivateSignal is that it should be private (and not e.g.
protected).

Moreover, we adjust QMetaProperty::notifySignalIndex to take
single-argument notify methods into consideration as well when
encontering an unresolved notify index.

Fixes: QTBUG-115989
Pick-to: 6.7
Change-Id: I8a056a15777f3132691e207b4b9ab6c2c9b2126d
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

1 files changed, 18 insertions, 0 deletions

diff --git a/tests/auto/tools/moc/tst_moc.cpp b/tests/auto/tools/moc/tst_moc.cpp
index 3a72e9bf4b..1726d09678 100644
--- a/tests/auto/tools/moc/tst_moc.cpp
+++ b/tests/auto/tools/moc/tst_moc.cpp
@@ -257,6 +257,24 @@ public:
 
 CreatableGadget creatableGadget; // Force the compiler to use the constructor
 
+struct ParentWithSignalWithArgument : QObject {
+    Q_OBJECT
+    Q_PROPERTY(int i READ i WRITE setI NOTIFY iChanged)
+
+public:
+    int i() const {return 0;}
+    void setI(int) {}
+
+signals:
+    void iChanged(int);
+};
+
+struct SignalWithArgumentInParent : ParentWithSignalWithArgument
+{
+    Q_OBJECT
+    Q_PROPERTY(int otherI READ i WRITE setI NOTIFY iChanged)
+};
+
 struct MyStruct {};
 struct MyStruct2 {};