Fix support for QJSValue as C++ signal parameter type, part 2

After commit 0e3380f we wouldn't crash
anymore, if QJSValue::UndefinedValue was provided as value for a
QJSValue C++ signal parameter. However that was not a complete fix for
the regression of commit aa869cb, as
other primitive values stored in QJSValue as QVariant were not
converted, so for example QJSValue(42). So let's fix this once and for
all by using QJSValuePrivate::valueForData, that handles all types of
QJSValuePrivate encodings.

Task-number: QTBUG-58133
Change-Id: Ib7c0461b18df6260ccd4bce729ae2348281eb7f3
Reviewed-by: Arnaud Vrac <avrac@freebox.fr>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

src/qml/qml/qqmlboundsignal.cpp

@@ -199,7 +199,7 @@ void QQmlBoundSignalExpression::evaluate(void **a)
  // for several cases (such as QVariant type and QObject-derived types)
  //args[ii] = engine->metaTypeToJS(type, a[ii + 1]);
  if (type == qMetaTypeId<QJSValue>()) {
- if (QV4::Value *v4Value = QJSValuePrivate::getValue(reinterpret_cast<QJSValue *>(a[ii + 1])))
+ if (QV4::Value *v4Value = QJSValuePrivate::valueForData(reinterpret_cast<QJSValue *>(a[ii + 1]), &callData->args[ii]))
  callData->args[ii] = *v4Value;
  else
  callData->args[ii] = QV4::Encode::undefined();

tests/auto/qml/qqmlecmascript/data/signalParameterTypes.qml

@@ -16,5 +16,11 @@ MyQmlObject
 
  onBasicSignal: root.mySignal(10, 19.2, Qt.rgba(1, 1, 0, 1), Qt.rgba(1, 0, 1, 1), MyQmlObject.EnumValue3, Qt.LeftButton)
 
- onQjsValueEmittingSignal: {}
+ property bool emittedQjsValueWasUndefined
+ property int emittedQjsValueAsInt
+
+ onQjsValueEmittingSignal: {
+ emittedQjsValueWasUndefined = value === undefined;
+ emittedQjsValueAsInt = value
+ }
 }

tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp

@@ -1410,7 +1410,6 @@ void tst_qqmlecmascript::signalParameterTypes()
  QVERIFY(object != 0);
 
  emit object->basicSignal();
- emit object->qjsValueEmittingSignal(QJSValue());
 
  QCOMPARE(object->property("intProperty").toInt(), 10);
  QCOMPARE(object->property("realProperty").toReal(), 19.2);
@@ -1419,6 +1418,12 @@ void tst_qqmlecmascript::signalParameterTypes()
  QVERIFY(object->property("enumProperty") == MyQmlObject::EnumValue3);
  QVERIFY(object->property("qtEnumProperty") == Qt::LeftButton);
 
+ emit object->qjsValueEmittingSignal(QJSValue());
+ QVERIFY(object->property("emittedQjsValueWasUndefined").toBool());
+ emit object->qjsValueEmittingSignal(QJSValue(42));
+ QVERIFY(!object->property("emittedQjsValueWasUndefined").toBool());
+ QCOMPARE(object->property("emittedQjsValueAsInt").value<int>(), 42);
+
  delete object;
 }