Fix regression from Qt 4 for deep group properties

Setting a property like someObject.font.family would cause an out-of-bounds
assertion in QList, called from QQmlCompiler::genValueTypeProperty. This
appears to be a regression from commit
5e970b84663f5398eb51d4575856d1a3c44df953, which replaced one -1 to
QMetaType::QVariant too many times. It appears the use of -1 is rather
deliberate here and not to indicate the use of a QVariant property.

The attached test verifies this as well as the successful setting of the
property at the end.

Task-number: QTBUG-31576
Change-Id: I237ea08847e1db31481a311ea8ec23a5ccc702d8
Reviewed-by: Matthew Vogt <matthew.vogt@qinetic.com.au>
Reviewed-by: Andrew den Exter <andrew.den.exter@qinetic.com.au>

4 files changed, 24 insertions, 1 deletions

diff --git a/src/declarative/qml/qdeclarativecompiler.cpp b/src/declarative/qml/qdeclarativecompiler.cpp
index 85ae3ebc..6734e0b4 100644
--- a/src/declarative/qml/qdeclarativecompiler.cpp
+++ b/src/declarative/qml/qdeclarativecompiler.cpp
@@ -1147,7 +1147,7 @@ void QDeclarativeCompiler::genValueTypeProperty(QDeclarativeParser::Object *obj,
     fetch.fetchValue.bindingSkipList = 0;
     fetch.line = prop->location.start.line;
 
-    if (obj->type == QMetaType::QVariant || output->types.at(obj->type).component) {
+    if (obj->type == -1 || output->types.at(obj->type).component) {
         // We only have to do this if this is a composite type.  If it is a builtin
         // type it can't possibly already have bindings that need to be cleared.
         foreach(Property *vprop, prop->value->valueProperties) {
diff --git a/tests/auto/declarative/qdeclarativelanguage/data/DeepComponent.qml b/tests/auto/declarative/qdeclarativelanguage/data/DeepComponent.qml
new file mode 100644
index 00000000..55753def
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativelanguage/data/DeepComponent.qml
@@ -0,0 +1,7 @@
+import QtQuick 1.1
+Item {
+    property alias someObject: text
+    Text {
+        id: text
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativelanguage/data/deepProperty.qml b/tests/auto/declarative/qdeclarativelanguage/data/deepProperty.qml
new file mode 100644
index 00000000..0787bded
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativelanguage/data/deepProperty.qml
@@ -0,0 +1,4 @@
+import QtQuick 1.1
+DeepComponent {
+    someObject.font.family: "test"
+}
diff --git a/tests/auto/declarative/qdeclarativelanguage/tst_qdeclarativelanguage.cpp b/tests/auto/declarative/qdeclarativelanguage/tst_qdeclarativelanguage.cpp
index 1574aa4a..8052f5fc 100644
--- a/tests/auto/declarative/qdeclarativelanguage/tst_qdeclarativelanguage.cpp
+++ b/tests/auto/declarative/qdeclarativelanguage/tst_qdeclarativelanguage.cpp
@@ -162,6 +162,8 @@ private slots:
 
     void compatibilitySemicolon();
 
+    void deepProperty();
+
 private:
     QDeclarativeEngine engine;
     void testType(const QString& qml, const QString& type, const QString& error);
@@ -2059,6 +2061,16 @@ void tst_qdeclarativelanguage::implicitImportsLast()
     QCOMPARE(QString(object2->metaObject()->className()), QLatin1String("QDeclarativeRectangle"));
 }
 
+void tst_qdeclarativelanguage::deepProperty()
+{
+    QDeclarativeComponent component(&engine, testFileUrl("deepProperty.qml"));
+    VERIFY_ERRORS(0);
+    QObject *o = component.create();
+    QVERIFY(o != 0);
+    QFont font = qvariant_cast<QFont>(qvariant_cast<QObject*>(o->property("someObject"))->property("font"));
+    QCOMPARE(font.family(), QStringLiteral("test"));
+}
+
 QTEST_MAIN(tst_qdeclarativelanguage)
 
 #include "tst_qdeclarativelanguage.moc"