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Getting error "Cannot read property 'setAttribute' of undefined"

See original GitHub issue

This issue can be quite overwhelming, happened to me when trying to use worker-dom with a pretty large library (https://github.com/handsontable/handsontable).

Error stack:

Uncaught TypeError: Cannot read property 'setAttribute' of undefined
    at Object.0 (mutator.js:69)
    at MUTATION_QUEUE.forEach.mutation (mutator.js:134)
    at Array.forEach (<anonymous>)
    at syncFlush (mutator.js:133)
    at requestAnimationFrame (mutator.js:122)

Code in mutator.js (Line 69 highlighted with a comment):

[1 /* CHARACTER_DATA */](mutation, target) {
        const value = mutation[18 /* value */];
        if (value) {
            // Sanitization not necessary for textContent.
            target.textContent = getString(value);
        } // **Line 69**
    },

Seems that target is undefined. I added some debugging code to storeNodes and it never stores the node with id that is being requested. id requested is 28 & storeNodes only gets called starting with 68.

Issue Analytics

State:
Created 5 years ago
Comments:5 (3 by maintainers)

Top GitHub Comments

2reactions

kristoferbaxtercommented, Oct 31, 2018

That is so awesome to see! Your patch makes sense, and we should address the issue.

We have an open PR #135 which likely fixes the issue in a different manner, by inverting the current hydration system… moving hydration from main-thread to worker.

2reactions

pbadenskicommented, Oct 31, 2018

I spent a bit more time debugging this. Based on my relatively shallow and mostly intuitive understanding I created a PoC fix: https://github.com/pricingmonkey/worker-dom/commit/146361baec36767971174d534fab854166898794

I think it might be that creating detached nodes might be causing an issue, since it was only document.body that was passed in during hydration. I extended hydration from single element to array of nodes & added passing of all nodes. It solved this issue.

P.S. Once this is resolved handsontable (which is quite complex JS library) rerenders via worker-dom! This project is absolutely amazing 😄

I know this might not be the right place… I’m extremely excited seeing how nicely the UI rerendering gets offloaded to the webworker, so let me share this:

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