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Fix runtime error in a broken clock challenge caused by missing element check

Open soralvy opened this issue 6 months ago • 5 comments

What’s the issue?

The Clock challenge component throws a runtime error because it tries to set the className on an element that does not yet exist in the DOM. Specifically, document.getElementById('time') returns null during the initial render, causing this error:

image

This PR adds a simple existence check before accessing the element’s className, preventing the runtime error while preserving the original logic

soralvy avatar Jul 11 '25 09:07 soralvy

Hi @soralvy!

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facebook-github-bot avatar Jul 11 '25 09:07 facebook-github-bot

Size changes

📦 Next.js Bundle Analysis for react-dev

This analysis was generated by the Next.js Bundle Analysis action. 🤖

This PR introduced no changes to the JavaScript bundle! 🙌

github-actions[bot] avatar Jul 11 '25 09:07 github-actions[bot]

Thank you for signing our Contributor License Agreement. We can now accept your code for this (and any) Meta Open Source project. Thanks!

facebook-github-bot avatar Jul 11 '25 10:07 facebook-github-bot

@gaearon is the error intentional for the challenge? The text sounds like it shouldn't, but looking at the history I don't see how this would have ever worked without an error?

rickhanlonii avatar Jul 11 '25 15:07 rickhanlonii

Any updates on that? @rickhanlonii @gaearon

soralvy avatar Sep 04 '25 18:09 soralvy