QmlCompiler: Use value type ctors

This allows us to do the relevant conversions in a more civilized way,
dropping the outputVariantConversion() method. The latter is brittle
because you have to manually add it to each instruction, and it uses
QMetaType::convert() which is actually not guaranteed to give the same
results as a QML type coercion.

Task-number: QTBUG-94807
Change-Id: I4d6d05a60beb3b4dfc3da6f0142de25667510904
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

1 files changed, 21 insertions, 0 deletions

diff --git a/src/qml/qml/qqmlglobal.cpp b/src/qml/qml/qqmlglobal.cpp
index 90889c2ea4..aa899b2592 100644
--- a/src/qml/qml/qqmlglobal.cpp
+++ b/src/qml/qml/qqmlglobal.cpp
@@ -94,6 +94,17 @@ static void callConstructor(
 }
 
 template<typename Allocate>
+static void fromVerifiedType(
+        const QMetaObject *mo, int ctorIndex, void *sData, Allocate &&allocate)
+{
+    const QMetaMethod ctor = mo->constructor(ctorIndex);
+    Q_ASSERT_X(ctor.parameterCount() == 1, "fromVerifiedType",
+               "Value type constructor must take exactly one argument");
+    callConstructor(mo, ctorIndex, sData, allocate());
+}
+
+
+template<typename Allocate>
 static bool fromMatchingType(
         const QMetaObject *mo, const QV4::Value &s, Allocate &&allocate)
 {
@@ -299,6 +310,16 @@ bool QQmlValueTypeProvider::createValueType(const QV4::Value &s, QMetaType metaT
     return false;
 }
 
+QVariant QQmlValueTypeProvider::constructValueType(
+        QMetaType resultMetaType, const QMetaObject *resultMetaObject,
+        int ctorIndex, void *ctorArg)
+{
+    QVariant result;
+    fromVerifiedType(resultMetaObject, ctorIndex, ctorArg,
+                     [&]() { return createVariantData(resultMetaType, &result); });
+    return result;
+}
+
 static QVariant fromJSValue(const QQmlType &type, const QJSValue &s, QMetaType metaType)
 {
     if (const auto valueTypeFunction = type.createValueTypeFunction()) {