make signal handlers understand QVariant again

Also, issue a warning if a type is not known to the meta-type system.
Backport of 508c9cd

Task-number: QTBUG-5060

Author: Kent Hansen

src/script/qscriptextqobject.cpp

@@ -1657,12 +1657,27 @@ void QScript::QObjectConnectionManager::execute(int slotIndex, void **argv)
         activation_data->m_members[i].object(nameId, i,
                                              QScriptValue::Undeletable
                                              | QScriptValue::SkipInEnumeration);
+        QScriptValueImpl actual;
         if (i < argc) {
-            int argType = QMetaType::type(parameterTypes.at(i));
-            activation_data->m_values[i] = eng->create(argType, argv[i + 1]);
+            void *arg = argv[i + 1];
+            QByteArray typeName = parameterTypes.at(i);
+            int argType = QMetaType::type(typeName);
+            if (!argType) {
+                if (typeName == "QVariant") {
+                    actual = eng->valueFromVariant(*reinterpret_cast<QVariant*>(arg));
+                } else {
+                    qWarning("QScriptEngine: Unable to handle unregistered datatype '%s' "
+                             "when invoking handler of signal %s::%s",
+                             typeName.constData(), meta->className(), method.signature());
+                    actual = eng->undefinedValue();
+                }
+            } else {
+                actual = eng->create(argType, arg);
+            }
         } else {
-            activation_data->m_values[i] = eng->undefinedValue();
+            actual = eng->undefinedValue();
         }
+        activation_data->m_values[i] = actual;
     }
 
     QScriptValueImpl senderObject;

tests/auto/qscriptextqobject/tst_qscriptextqobject.cpp

@@ -326,6 +326,10 @@ class MyQObject : public QObject
         { emit mySignalWithDefaultArg(arg); }
     void emitMySignalWithDefaultArg()
         { emit mySignalWithDefaultArg(); }
+    void emitMySignalWithVariantArg(const QVariant &arg)
+        { emit mySignalWithVariantArg(arg); }
+    void emitMySignalWithScriptEngineArg(QScriptEngine *arg)
+        { emit mySignalWithScriptEngineArg(arg); }
 
 public Q_SLOTS:
     void mySlot()
@@ -388,6 +392,8 @@ private Q_SLOTS:
     void myOtherOverloadedSignal(const QString &arg);
     void myOtherOverloadedSignal(int arg);
     void mySignalWithDefaultArg(int arg = 123);
+    void mySignalWithVariantArg(const QVariant &arg);
+    void mySignalWithScriptEngineArg(QScriptEngine *arg);
 
 protected:
     void connectNotify(const char *signal) {
@@ -1501,6 +1507,29 @@ void tst_QScriptExtQObject::connectAndDisconnect()
     m_myObject->emitMyOtherOverloadedSignal(123);
     QVERIFY(!m_engine->evaluate("gotSignal").toBoolean());
 
+    // signal with QVariant arg: argument conversion should work
+    m_myObject->clearConnectedSignal();
+    QVERIFY(m_engine->evaluate("myObject.mySignalWithVariantArg.connect(myHandler)").isUndefined());
+    QCOMPARE(m_myObject->connectedSignal().constData(), SIGNAL(mySignalWithVariantArg(QVariant)));
+    m_engine->evaluate("gotSignal = false");
+    m_myObject->emitMySignalWithVariantArg(123);
+    QCOMPARE(m_engine->evaluate("gotSignal").toBoolean(), true);
+    QCOMPARE(m_engine->evaluate("signalArgs.length").toNumber(), 1.0);
+    QCOMPARE(m_engine->evaluate("signalArgs[0]").toNumber(), 123.0);
+    QVERIFY(m_engine->evaluate("myObject.mySignalWithVariantArg.disconnect(myHandler)").isUndefined());
+
+    // signal with argument type that's unknown to the meta-type system
+    m_myObject->clearConnectedSignal();
+    QVERIFY(m_engine->evaluate("myObject.mySignalWithScriptEngineArg.connect(myHandler)").isUndefined());
+    QCOMPARE(m_myObject->connectedSignal().constData(), SIGNAL(mySignalWithScriptEngineArg(QScriptEngine*)));
+    m_engine->evaluate("gotSignal = false");
+    QTest::ignoreMessage(QtWarningMsg, "QScriptEngine: Unable to handle unregistered datatype 'QScriptEngine*' when invoking handler of signal MyQObject::mySignalWithScriptEngineArg(QScriptEngine*)");
+    m_myObject->emitMySignalWithScriptEngineArg(m_engine);
+    QCOMPARE(m_engine->evaluate("gotSignal").toBoolean(), true);
+    QCOMPARE(m_engine->evaluate("signalArgs.length").toNumber(), 1.0);
+    QVERIFY(m_engine->evaluate("signalArgs[0]").isUndefined());
+    QVERIFY(m_engine->evaluate("myObject.mySignalWithScriptEngineArg.disconnect(myHandler)").isUndefined());
+
     // connect(object, function)
     m_engine->evaluate("otherObject = { name:'foo' }");
     QVERIFY(m_engine->evaluate("myObject.mySignal.connect(otherObject, myHandler)").isUndefined());