QQmlListReference: Allow construction from a QVariant

Currently there is no public API to transform a QVariant holding a
QQmlListProperty into a QQmlListReference. We cannot pass
QQmlListProperty itself as that is templated. The metatype-based casting
is somewhat evil, but not more so than what we already have in the other
ctor.

Change-Id: I2d56499b1fd188613bc71016cb00ec23081d3cea
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>

1 files changed, 22 insertions, 0 deletions

diff --git a/tests/auto/qml/qqmllistreference/tst_qqmllistreference.cpp b/tests/auto/qml/qqmllistreference/tst_qqmllistreference.cpp
index bf5ee92374..c6accb3908 100644
--- a/tests/auto/qml/qqmllistreference/tst_qqmllistreference.cpp
+++ b/tests/auto/qml/qqmllistreference/tst_qqmllistreference.cpp
@@ -179,6 +179,17 @@ void tst_qqmllistreference::qmllistreference()
 
     tt.data.append(&tt);
     QCOMPARE(r.count(), 1);
+
+    const QMetaObject *m = tt.metaObject();
+    const int index = m->indexOfProperty("data");
+    const QMetaProperty prop = m->property(index);
+    const QVariant var = prop.read(&tt);
+
+    QQmlListReference fromVar(var);
+    QVERIFY(fromVar.isValid());
+    QCOMPARE(fromVar.count(), 1);
+    fromVar.append(&tt);
+    QCOMPARE(tt.data.count(), 2);
 }
 
 void tst_qqmllistreference::qmllistreference_invalid()
@@ -805,6 +816,17 @@ void tst_qqmllistreference::engineTypes()
     QVERIFY(ref.listElementType());
     QVERIFY(ref.listElementType() != &QObject::staticMetaObject);
 
+
+    const QMetaObject *m = o->metaObject();
+    const int index = m->indexOfProperty("myList");
+    const QMetaProperty prop = m->property(index);
+    const QVariant var = prop.read(o);
+
+    QQmlListReference fromVar(var, &engine);
+    QVERIFY(fromVar.isValid());
+    QCOMPARE(fromVar.count(), 2);
+    QCOMPARE(fromVar.listElementType(), ref.listElementType());
+
     delete o;
 }