Web page runJavascript always crashes jvm when you try to use the returned object

[mchistovib]

Describe the bug
Web page runJavascript always crashes jvm when you try to use the returned object

To Reproduce
Steps to reproduce the behavior:
Just run this code:

package ngMvp;

import io.qt.QtUtilities;
import io.qt.core.QCoreApplication;
import io.qt.core.QUrl;
import io.qt.core.Qt;
import io.qt.quick.QQuickWindow;
import io.qt.quick.QSGRendererInterface;
import io.qt.webengine.core.QWebEnginePage;
import io.qt.webengine.quick.QtWebEngineQuick;
import io.qt.webengine.widgets.QWebEngineView;
import io.qt.widgets.QApplication;

import java.net.URISyntaxException;
import java.util.function.Consumer;


public class WebPage {

    // test commit
    public static void main(String[] args) throws URISyntaxException {
        QtWebEngineQuick.initialize();
        QtUtilities.initializePackage("io.qt.webengine.widgets");
        QCoreApplication.setAttribute(Qt.ApplicationAttribute.AA_ShareOpenGLContexts);
        QQuickWindow.setGraphicsApi(QSGRendererInterface.GraphicsApi.OpenGLRhi);
        QApplication.initialize(args);

        QWebEngineView view = new QWebEngineView();
        QWebEnginePage page = new QWebEnginePage(view);
        view.setPage(page);
        page.load(new QUrl("http://info.cern.ch/"));
        page.runJavaScript("window", new Consumer<Object>() {
            @Override
            public void accept(Object o) {
               System.out.println("test "  + o); // always creates a crash if you interact with this object in any way
            }
        });
        view.show();

        QApplication.exec();
        QApplication.shutdown();
    }
}

It also crashes when you stay in the breakpoint of this line for too long - I assume it happens because debugger is calling .toString() for the returned o object

Expected behavior
It shouldn't crash at all.

System (please complete the following information):

• OS: Windows 10
• Java version 11
• QtJambi version 6.2.6
• Qt version 6.2.5

[mchistovib]

I assume that result object is destroyed on cpp code before being returned to this callback

[omix]

There seems to be a problem when QVariant is converted to Java object. The actual value is converted to QHash but QHash.toString() crashes because there is something broken.
Can you confirm that the program does not crash when you change as follows?

System.out.println("test " + o.getClass());

[mchistovib]

@omix getClass() doesn't crash because it's not using the native object link. Any method that uses QtJambi_LibraryUtilities.internal.nativeId(this) in it crashes the app, for example toString(), size(), etc

[omix]

QVariant containing QMap was erroneously converted to Java QHash not QMap. Thus, accessing the QMap value from Java led to crash.
Is solved in the next release.