QmlCompiler: Relax shadowing check

If we detect a property or method as potentially shadowed, we don't have
to abandon all hope. We can still retrieve it as untyped var. Since
there are a number of things we can do with untyped var, this may still
be useful.

In the same sense, we need to treat function calls as untyped when the
function in question can be shadowed. Calling functions with var
arguments and return types leads to some more interesting situations in
the call frame setup, so we fix that, too.

Task-number: QTBUG-112480
Change-Id: I238d1cf04951f390c73e14ed9e299f2aa72b68cb
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

3 files changed, 49 insertions, 0 deletions

diff --git a/tests/auto/qml/qmlcppcodegen/data/CMakeLists.txt b/tests/auto/qml/qmlcppcodegen/data/CMakeLists.txt
index 85ac7e6e2e..48fcf3bec0 100644
--- a/tests/auto/qml/qmlcppcodegen/data/CMakeLists.txt
+++ b/tests/auto/qml/qmlcppcodegen/data/CMakeLists.txt
@@ -181,6 +181,7 @@ set(qml_files
     scopeVsObject.qml
     script.js
     script.mjs
+    shadowedMethod.qml
     shared/Slider.qml
     shifts.qml
     signal.qml
diff --git a/tests/auto/qml/qmlcppcodegen/data/shadowedMethod.qml b/tests/auto/qml/qmlcppcodegen/data/shadowedMethod.qml
new file mode 100644
index 0000000000..590fb40b17
--- /dev/null
+++ b/tests/auto/qml/qmlcppcodegen/data/shadowedMethod.qml
@@ -0,0 +1,35 @@
+pragma Strict
+import QtQuick
+
+Item {
+    component B: Item {
+        function contains(point: point) : string {
+            return "b"
+        }
+    }
+
+
+    component C: Item {
+        function contains(point: point) : string {
+            return "c"
+        }
+    }
+
+    property Item a: Item {}
+    property B b: B {}
+    property C c: C {}
+
+    function doThing() : var { return a.contains(Qt.point(0, 0)) }
+
+    property var athing;
+    property var bthing;
+    property var cthing;
+
+    Component.onCompleted: {
+        athing = doThing();
+        a = b;
+        bthing = doThing();
+        a = c;
+        cthing = doThing();
+    }
+}
diff --git a/tests/auto/qml/qmlcppcodegen/tst_qmlcppcodegen.cpp b/tests/auto/qml/qmlcppcodegen/tst_qmlcppcodegen.cpp
index 25002acd3f..e3292b52f3 100644
--- a/tests/auto/qml/qmlcppcodegen/tst_qmlcppcodegen.cpp
+++ b/tests/auto/qml/qmlcppcodegen/tst_qmlcppcodegen.cpp
@@ -183,6 +183,7 @@ private slots:
     void jsArrayMethods();
     void jsArrayMethodsWithParams_data();
     void jsArrayMethodsWithParams();
+    void shadowedMethod();
 };
 
 void tst_QmlCppCodegen::initTestCase()
@@ -3754,6 +3755,18 @@ void tst_QmlCppCodegen::jsArrayMethodsWithParams()
     QCOMPARE(object->property("listPropertyLastIndexOf"), check->property("jsArrayLastIndexOf"));
 }
 
+void tst_QmlCppCodegen::shadowedMethod()
+{
+    QQmlEngine e;
+    QQmlComponent c(&e, QUrl(u"qrc:/qt/qml/TestTypes/shadowedMethod.qml"_s));
+    QVERIFY2(c.isReady(), qPrintable(c.errorString()));
+    QScopedPointer<QObject> o(c.create());
+    QVERIFY(!o.isNull());
+    QCOMPARE(o->property("athing"), QVariant::fromValue<bool>(false));
+    QCOMPARE(o->property("bthing"), QVariant::fromValue(u"b"_s));
+    QCOMPARE(o->property("cthing"), QVariant::fromValue(u"c"_s));
+}
+
 QTEST_MAIN(tst_QmlCppCodegen)
 
 #include "tst_qmlcppcodegen.moc"