document.implementation.createHTMLDocument cicumvents patchDocument

[quickshiftin]

I'm trying to load Full Story via Partytown. I'm using the partytown repo and following the Local Development setup to test the integration in isolation as it is not a currently supported script.

The Full Story script is fetched via a reverse proxy, then when it starts being executed via Partytown, something blows up.

TypeError: Cannot set properties of undefined (setting 'id')
    at new e (fs.js:formatted:2601:68)
    at Object.302 (fs.js:formatted:2597:30)
    at n (fs.js:formatted:12491:28)
    at eval (fs.js:formatted:12515:13)
    at Proxy.eval (fs.js:formatted:12516:10)
    at run (partytown-ww-sw.js?v=0.5.4-dev1651873848564:859:37)
    at partytown-ww-sw.js?v=0.5.4-dev1651873848564:1879:33

Drilling into the error, it looks like Full Story is trying to create an element on Document object they've created. Essentially these two lines of code:

var e = document.implementation.createHTMLDocument("");
(t = e.createElement("base")).id

The second line fails, because createElement, which is an instance of WorkerBase returns undefined. Digging in a bit it looks like the value supplied for winId from the createElement function, (const winId = this[WinIdKey];) doesn't map to an environment. So when getOrCreateNodInstance tries to lookup the environment it fails to do so.

I'll plan to try to further isolate this, but that's what I have found so far. Any help or clues would be appreciated. I'm also attaching the debugging output in case that is helpful.

[quickshiftin]

I got it down to some trivial reproducible code:

// This works
b = document.createElement("base") // b is an instance of WorkerBase
console.log('base element?', b)

// This is broken
var e = document.implementation.createHTMLDocument("");
t = e.createElement("base") // t is undefined
console.log('base element?', t)

Could we potentially be missing a call to createEnvironment in the createHTMLDocument implementation?

[steve8708]

hey @quickshiftin - we've just created an issue template, could you update your issue here to provide all the information the template asks for? it'll help us look into your issue https://github.com/BuilderIO/partytown/issues/new?assignees=&labels=&template=bug_report.md&title=

pasting below to make things easier:

---

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Reproduction link
Please include a link to a Stackblitz or Codesandbox reproducing the issue. We will need to see the issue reproduced with hand-written code - we can't debug giant minified third party scripts directly. If you do not include a clean and simple reproduction of your issue, we won't be able to look into it until you do.

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots
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Additional context
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[adamdbradley]

Fixed in #177