Hydration fails when a component is used on multiple pages

Version: 1.1.0-next.3

Steps to reproduce

1. Render a hydrated component on multiple pages
2. Build/serve
3. Load in browser

Expected behavior

The component will hydrate on each page.

Observed behavior

No JS is loaded at all.

Apparent cause

Any shared component with hydration is bundled as a shared chunk, but the shared chunk is excluded from hydrateBindings, and doesn’t appear to be referenced anywhere else. If I comment out that check it does hydrate as expected.

I was tempted to offer a PR removing that check, but I can’t shake the feeling that there’s a reason it’s there and the intent was to handle that case differently.

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Related side note: in terms of contribution, my usual approach is to write a failing test exercising my bug, then fix to make the test pass. But at present Microsite doesn’t appear to have a test suite. Is that something you’d be interested in? If so do you have a preferred test framework? I’d be happy to look into setting up CI for any tests I contribute, and to try to increase coverage as I contribute.

[eyelidlessness]

Without getting too hung up on the big testing question, I strongly suspect the resolution of this is pretty simple:

1. Shared hydration chunks and shared static chonks should go to different manual chunks
2. Shared hydration chunks should go to the bundle
3. Eventually the implicit TODO should be addressed and allow more granular code splitting
4. For my own use I’m gonna want to bundle up everything headed to the client and un-split but that’s obviously not a requirement here. Just stating my use case!

[eyelidlessness]

Great news! I got a little proof of concept with Estrella working, and goodness it is fast! And it took very little fuss to get going. I’m going to clean up some mess, setup a GitHub Action, and push up a PR. It’s not a huge diff, but I think I’d like to keep test setup separate from fixing this issue to get a meaningful win. Hopefully ready within the hour!