QtQml: Clean up QQmlMetaObject::canConvert()

I don't see how the previous implementation makes any sense. It seems to
be a remnant of a time when QMetaObject::inherits() didn't work
reliably.

Task-number: QTBUG-94807
Change-Id: I9b7a25aa641185c263ddc6d91553400259e4a311
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

2 files changed, 5 insertions, 23 deletions

diff --git a/src/qml/qml/qqmlmetaobject.cpp b/src/qml/qml/qqmlmetaobject.cpp
index e84c5a366e..d5f1fb3b96 100644
--- a/src/qml/qml/qqmlmetaobject.cpp
+++ b/src/qml/qml/qqmlmetaobject.cpp
@@ -8,28 +8,6 @@
 
 QT_BEGIN_NAMESPACE
 
-// Returns true if \a from is assignable to a property of type \a to
-bool QQmlMetaObject::canConvert(const QQmlMetaObject &from, const QQmlMetaObject &to)
-{
-    Q_ASSERT(!from.isNull() && !to.isNull());
-
-    auto equal = [] (const QMetaObject *lhs, const QMetaObject *rhs) -> bool {
-        return lhs == rhs || (lhs && rhs && lhs->d.stringdata == rhs->d.stringdata);
-    };
-
-    const QMetaObject *tom = to.metaObject();
-    if (tom == &QObject::staticMetaObject) return true;
-
-    const QMetaObject *fromm = from.metaObject();
-    while (fromm) {
-        if (equal(fromm, tom))
-            return true;
-        fromm = fromm->superClass();
-    }
-
-    return false;
-}
-
 void QQmlMetaObject::resolveGadgetMethodOrPropertyIndex(QMetaObject::Call type, const QMetaObject **metaObject, int *index)
 {
     int offset;
diff --git a/src/qml/qml/qqmlmetaobject_p.h b/src/qml/qml/qqmlmetaobject_p.h
index cc3cc6af79..288779c74c 100644
--- a/src/qml/qml/qqmlmetaobject_p.h
+++ b/src/qml/qml/qqmlmetaobject_p.h
@@ -67,7 +67,11 @@ public:
     bool constructorParameterTypes(int index, ArgTypeStorage *dummy, QByteArray *unknownTypeError) const;
 
 
-    static bool canConvert(const QQmlMetaObject &from, const QQmlMetaObject &to);
+    static bool canConvert(const QQmlMetaObject &from, const QQmlMetaObject &to)
+    {
+        Q_ASSERT(!from.isNull() && !to.isNull());
+        return from.metaObject()->inherits(to.metaObject());
+    }
 
     // static_metacall (on Gadgets) doesn't call the base implementation and therefore
     // we need a helper to find the correct meta object and property/method index.