chore: remove redundant hydration code

[trueadm]

Turns out we don't need to set $$fragment to undefined anymore. Also noticed some suspect code just below it that should probably be fixed too.

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Latest commit: 317de4a

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Name	Status	Preview	Comments	Updated (UTC)
svelte-5-preview	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Nov 30, 2023 10:11am

[dummdidumm]

Where do we set it do undefined then? Because we do set it, and to avoid memory leaks, we should unset it somewhere, right?

[dummdidumm]

Somewhere in line 1400 at render.js I vaguely remember having run into this, and checking explicitly for null there. That may be needed to adjusted, too.

[trueadm]

Somewhere in line 1400 at render.js I vaguely remember having run into this, and checking explicitly for null there. That may be needed to adjusted, too.

Nice. Removed that now as it shouldn't be needed.

Where do we set it do undefined then? Because we do set it, and to avoid memory leaks, we should unset it somewhere, right?

get_hydration_fragment used to assign the fragment to the node at one point I guess? We can re-explore memory leaks but this doesn't ever get set anymore.

[dummdidumm]

get_hydration_fragment used to assign the fragment to the node at one point I guess? We can re-explore memory leaks but this doesn't ever get set anymore.

That's not true, $$fragment is still set within capture_fragment_from_node in operations.js. I therefore think it should be set back to undefined somewhere once it's no longer needed.

[trueadm]

@dummdidumm Yeah, so get_hydration_fragment used to use next_sibling, but at some point it was changed to .nextSibling. The next_sibling logic triggered capture_fragment_from_node.

[dummdidumm]

I don't fully understand what you mean by that sentence. What I mean is, that there are still usages of $$fragment, and now it's not set to undefined anymore anywhere, and that seems like a potential memory leak.

[trueadm]

@dummdidumm Pushed some cleanup logic.

[benmccann]

This might not be an accurate description anymore now that it's adding rather than removing code. I don't care so much about the changeset, but just thought it was funny 😆