qmltc: Add some sugar for generated reference-type-list properties

When compiling a reference type list with qmltc into a QQmlListProperty,
also generate helper methods to make the manipulation of those lists by
the user easier in c++.

For a list myList, generate the methods myListAt(), myListAppend(), ...
as shown in the Birthdayparty example.
Also add some documentation about the ownership of the arguments, and
tests to see if the list can be accessed from C++.

Task-number: QTBUG-107570
Change-Id: Iec0041015311639ead39660fdccf147749566592
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

2 files changed, 51 insertions, 0 deletions

diff --git a/tests/auto/qml/qmltc/QmltcTests/listProperty.qml b/tests/auto/qml/qmltc/QmltcTests/listProperty.qml
index b2f16fe11c..1f87f7fb9e 100644
--- a/tests/auto/qml/qmltc/QmltcTests/listProperty.qml
+++ b/tests/auto/qml/qmltc/QmltcTests/listProperty.qml
@@ -11,5 +11,21 @@ QtObject {
         QtObject { id: a2; property string hello: "Hello from parent.children[1]" }
     ]
 
+    property QtObject appendMe: QtObject { id: a3; property string hello: "Hello from parent.children[2]" }
+
     ids: [a, a1, a2]
+
+    property list<int> myList: [1,2,3,4]
+
+    property int count: myList.length
+
+    property int firstCount
+    property int secondCount
+
+    Component.onCompleted: {
+        firstCount = count
+        myList.push(43)
+        secondCount = count
+    }
+
 }
diff --git a/tests/auto/qml/qmltc/tst_qmltc.cpp b/tests/auto/qml/qmltc/tst_qmltc.cpp
index 2c5a164989..731d90af20 100644
--- a/tests/auto/qml/qmltc/tst_qmltc.cpp
+++ b/tests/auto/qml/qmltc/tst_qmltc.cpp
@@ -1526,6 +1526,11 @@ void tst_qmltc::listProperty()
     QQmlEngine e;
     PREPEND_NAMESPACE(listProperty) created(&e);
 
+    QQmlComponent c(&e);
+    c.loadUrl(QUrl("qrc:/qt/qml/QmltcTests/listProperty.qml"));
+    QScopedPointer<QObject> fromEngine(c.create());
+    QVERIFY2(fromEngine, qPrintable(c.errorString()));
+
     QCOMPARE(created.hello(), QStringLiteral("Hello from parent"));
 
     QQmlListReference ref(&created, "children");
@@ -1544,6 +1549,36 @@ void tst_qmltc::listProperty()
     QCOMPARE(refIds.at(0), &created);
     QCOMPARE(refIds.at(1), ref.at(0));
     QCOMPARE(refIds.at(2), ref.at(1));
+
+    QCOMPARE(fromEngine->property("firstCount"), 4);
+    QCOMPARE(fromEngine->property("secondCount"), 5);
+
+    QCOMPARE(created.firstCount(), 4);
+    QCOMPARE(created.secondCount(), 5);
+
+    QCOMPARE(created.childrenCount(), 2);
+    QCOMPARE(created.childrenAt(0)->property("hello"), u"Hello from parent.children[0]"_s);
+    QCOMPARE(created.childrenAt(1)->property("hello"), u"Hello from parent.children[1]"_s);
+
+    created.childrenAppend(created.appendMe());
+    QCOMPARE(created.childrenCount(), 3);
+    QCOMPARE(created.childrenAt(0)->property("hello"), u"Hello from parent.children[0]"_s);
+    QCOMPARE(created.childrenAt(1)->property("hello"), u"Hello from parent.children[1]"_s);
+    QCOMPARE(created.childrenAt(2)->property("hello"), u"Hello from parent.children[2]"_s);
+
+    created.childrenReplace(0, created.appendMe());
+    QCOMPARE(created.childrenCount(), 3);
+    QCOMPARE(created.childrenAt(0)->property("hello"), u"Hello from parent.children[2]"_s);
+    QCOMPARE(created.childrenAt(1)->property("hello"), u"Hello from parent.children[1]"_s);
+    QCOMPARE(created.childrenAt(2)->property("hello"), u"Hello from parent.children[2]"_s);
+
+    created.childrenRemoveLast();
+    QCOMPARE(created.childrenCount(), 2);
+    QCOMPARE(created.childrenAt(0)->property("hello"), u"Hello from parent.children[2]"_s);
+    QCOMPARE(created.childrenAt(1)->property("hello"), u"Hello from parent.children[1]"_s);
+
+    created.childrenClear();
+    QCOMPARE(created.childrenCount(), 0);
 }
 
 void tst_qmltc::listPropertiesWithTheSameName()