Layout slot is not updating after updating Svelte to 3.24.1

[ozzym1096]

With hotReload: true, the layout slot will not update when navigating to a different route. There is no problem with HMR when Svelte v3.24.0 is installed.

[n-pn]

confirmed. not working with svelte ^3.24.0. had to downgrade to ~3.23.2 to make it works again.

[slightlyfaulty]

It looks like this might have already been fixed in rixo/svelte-hmr#18, but svelte-loader-hot doesn't seem to be compatible with the later versions of svelte-hmr.

[rixo]

Thanks for the feedback.

Indeed, there was an incompatibility with Svelte 3.24.1 that was fixed in latest svelte-hmr, and svelte-loader has not been updated to use that yet.

I have just released the required changes as svelte-loader-hot@0.3.1-1 (yarn add -D svelte-loader-hot@next). Can someone try this next version and see if it solves this issue? (Checking if nothing is obviously broken would be nice too!)

Unfortunately, that wouldn't explain @nipinium's problem since, as far as I know, svelte@3.24.0 was not affected by the problem fixed by last version of svelte-hmr...

To be totally frank, I don't really get what's the issue here... Given we're talking about layouts & slots, I've tried my luck with sapper-template-hot#webpack example, with latest Svelte (3.24.1 indeed), but I don't seem to be able to reproduce the problem mentioned here, neither with current version of svelte-loader-hot, nor with the next version I've just pushed... HMR updates seems to work correctly both when I modify _layout.svelte or a page file...

Maybe some (all?) of you are talking about Routify? Can anyone share a complete example illustrating this problem?

[slightlyfaulty]

Just tested and can confirm the update fixes the issue for me. Thanks @rixo!

In my case I wasn't using slots (or Routify), there were just some parts of reactivity not updating properly in a relatively small component hierarchy. I've managed to reproduce the issue as minimally as I can: svelte-loader-hot-repro-8

I assume @nipinium was indeed using 3.24.1, he was just using the ^3.24.0 version range.

[rixo]

Good to hear, thanks for the feedback @slightlyfaulty. I've published the new version as a patch release (v0.3.1), so people can get support for Svelte 3.24.1 without having to think about it (big thanks to @dominikg for the actual fix in svelte-hmr, btw).

I have personally stopped using Webpack for Svelte projects, so the development of svelte-loader-hot has been lagging a bit behind... This kind of issues really helps to get some focus on what's important, and a big boost to motivation, to know that this work is actually useful to someone. And so, don't hesitate to open them when needed!

Cheers guys!

[ozzym1096]

Thank you for the quick patch @rixo! I will go ahead and close this issue.

I'm not familiar at all with the inner workings of Svelte, but, like you, I couldn't find anything that would have caused an issue.
And I was actually working on a demo site using Sapper when I noticed the issue.

[n-pn]

thanks for the quick fix, @rixo.
I had expected this would take weeks to happen.