QQmlMetaType: Don't duplicate notify signals for extended types

We have to add the methods first, so that the properties can be
associated with their proper notification signals once we add them. If
we add the properties first, the "missing" notification signals are
synthesized.

Pick-to: 6.2 6.3
Fixes: QTBUG-101155
Change-Id: I1aacbf33a24f7a98d05dece77c804bd7cba8a041
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

src/qml/qml/qqmlmetatype.cpp

@@ -253,20 +253,7 @@ void QQmlMetaType::clone(QMetaObjectBuilder &builder, const QMetaObject *mo,
         }
     }
 
-    // Clone Q_PROPERTY
-    for (int ii = mo->propertyOffset(); ii < mo->propertyCount(); ++ii) {
-        QMetaProperty property = mo->property(ii);
-
-        int otherIndex = ignoreEnd->indexOfProperty(property.name());
-        if (otherIndex >= ignoreStart->propertyOffset() + ignoreStart->propertyCount()) {
-            builder.addProperty(QByteArray("__qml_ignore__") + property.name(), QByteArray("void"));
-            // Skip
-        } else {
-            builder.addProperty(property);
-        }
-    }
-
-    // Clone Q_METHODS
+    // Clone Q_METHODS - do this first to avoid duplicating the notify signals.
     for (int ii = mo->methodOffset(); ii < mo->methodCount(); ++ii) {
         QMetaMethod method = mo->method(ii);
 
@@ -290,6 +277,19 @@ void QQmlMetaType::clone(QMetaObjectBuilder &builder, const QMetaObject *mo,
             m.setAccess(QMetaMethod::Private);
     }
 
+    // Clone Q_PROPERTY
+    for (int ii = mo->propertyOffset(); ii < mo->propertyCount(); ++ii) {
+        QMetaProperty property = mo->property(ii);
+
+        int otherIndex = ignoreEnd->indexOfProperty(property.name());
+        if (otherIndex >= ignoreStart->propertyOffset() + ignoreStart->propertyCount()) {
+            builder.addProperty(QByteArray("__qml_ignore__") + property.name(), QByteArray("void"));
+            // Skip
+        } else {
+            builder.addProperty(property);
+        }
+    }
+
     // Clone Q_ENUMS
     for (int ii = mo->enumeratorOffset(); ii < mo->enumeratorCount(); ++ii) {
         QMetaEnum enumerator = mo->enumerator(ii);

tests/auto/qml/qqmllanguage/data/foreignExtended.qml

@@ -5,12 +5,17 @@ QtObject {
     property Foreign foreign: Foreign {
         objectName: "foreign"
     }
-    property Extended extended: Extended {}
+    property Extended extended: Extended {
+        objectName: "extended"
+        property int changeCount: 0
+        onExtensionChanged: ++changeCount
+    }
     property ForeignExtended foreignExtended: ForeignExtended {
         objectName: "foreignExtended"
     }
 
     property int extendedBase: extended.base
+    property int extendedChangeCount: extended.changeCount
 
     property int extendedInvokable: extended.invokable()
     property int extendedSlot: extended.slot()

tests/auto/qml/qqmllanguage/testtypes.h

@@ -1470,13 +1470,23 @@ public:
 class Extension : public QObject
 {
     Q_OBJECT
-    Q_PROPERTY(int extension READ extension CONSTANT)
+    Q_PROPERTY(int extension READ extension WRITE setExtension NOTIFY extensionChanged FINAL)
 public:
     Extension(QObject *parent = nullptr) : QObject(parent) {}
-    int extension() const { return 42; }
+    int extension() const { return ext; }
+    void setExtension(int e) {
+        if (e != ext) {
+            ext = e;
+            emit extensionChanged();
+        }
+    }
     Q_INVOKABLE int invokable() { return 123; }
+Q_SIGNALS:
+    void extensionChanged();
 public slots:
     int slot() { return 456; }
+private:
+    int ext = 42;
 };
 
 class Extended : public QObject

tests/auto/qml/qqmllanguage/tst_qqmllanguage.cpp

@@ -5636,9 +5636,20 @@ void tst_qqmllanguage::extendedForeignTypes()
     QScopedPointer<QObject> o(component.create());
     QVERIFY(!o.isNull());
 
+    QObject *extended = o->property("extended").value<QObject *>();
+    QVERIFY(extended);
+    QSignalSpy extensionChangedSpy(extended, SIGNAL(extensionChanged()));
+
     QCOMPARE(o->property("extendedBase").toInt(), 43);
     QCOMPARE(o->property("extendedExtension").toInt(), 42);
     QCOMPARE(o->property("foreignExtendedExtension").toInt(), 42);
+
+    QCOMPARE(extensionChangedSpy.count(), 0);
+    extended->setProperty("extension", 44);
+    QCOMPARE(extensionChangedSpy.count(), 1);
+    QCOMPARE(o->property("extendedChangeCount").toInt(), 1);
+    QCOMPARE(o->property("extendedExtension").toInt(), 44);
+
     QCOMPARE(o->property("foreignObjectName").toString(), QLatin1String("foreign"));
     QCOMPARE(o->property("foreignExtendedObjectName").toString(), QLatin1String("foreignExtended"));
     QCOMPARE(o->property("extendedInvokable").toInt(), 123);