#1897 TypeError: Cannot modify readonly property: constructor.

[RBRi]

This code fails

    public static void main(String[] args) throws Exception {
        final WebClient webClient = new WebClient(BrowserVersion.CHROME);

        final HtmlPage webPage = (HtmlPage) webClient.getPage("https://www.marinetraffic.com/");
        System.out.println(webPage.asXml());

    }

[RBRi]

Had done a lot of debugging but was not able to fix this so far.
What i found:

• this is new with our current core-js snapshot / does not occur with 2.27
• the exception is thrown from com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.initialize(WebWindow); the problematic calls are ((FunctionObject) function).addAsConstructor(window, prototype);
• the exeption is not thrown when calling the init for the first window; the init is called a second time because the code creates an iFrame and init is called for this iframe
• i was not able to build a minimal test case
• the problem ocures when init reaches the classes Option, MutationObserver, webkitURL, TransitionEvent and WebKitAnimationEvent

[RBRi]

Minimal progress - the reason seems to be because the script switches to scrict mode.

[RBRi]

I think i have an idea now what is going on here

[RBRi]

Test case added
com.gargoylesoftware.htmlunit.html.HtmlInlineFrame2Test.createIframeFromStrictFunction()

[Michael Anderson]

Any update on this?

[Stas Agarkov]

The error is reproduced on the site https://beru.ru/

[PRA]

Fix is broken. See https://sourceforge.net/p/htmlunit/bugs/1974/