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Cannot call method "getElementsByClassName" of undefined

See original GitHub issue

EcmaError: lineNumber=[5] column=[0] lineSource=[ const prevButton = carousel.parentElement.getElementsByClassName("carousel-previous-button")[0];] name=[TypeError] sourceName=[https://www.fdic.gov/assets/javascript/carousels.js] message=[TypeError: Cannot call method "getElementsByClassName" of undefined (https://www.fdic.gov/assets/javascript/carousels.js#5)] com.gargoylesoftware.htmlunit.ScriptException: TypeError: Cannot call method "getElementsByClassName" of undefined (https://www.fdic.gov/assets/javascript/carousels.js#5) at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:891) at net.sourceforge.htmlunit.corejs.javascript.Context.call(Context.java:619) at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.call(ContextFactory.java:537) at com.gargoylesoftware.htmlunit.javascript.HtmlUnitContextFactory.callSecured(HtmlUnitContextFactory.java:354)

Getting the above JavaScript exception when trying to scrape https://www.fdic.gov/news/press-releases/2020/

Issue Analytics

State:
Created 3 years ago
Comments:11 (7 by maintainers)

Top GitHub Comments

1reaction

rbricommented, Aug 3, 2020

Does your change just ignores the exception?

You think i need a whole week only to suppress the exception?

The page includes several js parts - usually huge js scripts. It will not be that easy to figure out why some js parts are working different from real browsers. If you like to get this fixed you can help to nail down the problem to the problematic function. You can have a look at https://htmlunit.sourceforge.io/submittingJSBugs.html for some hints how to do it.

1reaction

rbricommented, Jul 29, 2020

Will try to get this done during this week.

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