fix: prevent component pre-mounting in async boundaries #16633
+20
−23
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Note: Follows up #16624.
failing test case w/ 16624 | The same test case with this PR
Description:
This PR changes how deferred components and their effects are mounted. Earlier components inside svelte:boundary with await were being mounted immediately as offscreen fragments and then replaced/swapped after the promises resolved, triggering effects immediately.
In this PR mounting is deferred until promise is resolved (no offscreen fragment is created. Not sure if this has any implications 🤞).
So, this solves the original issue of changed lifecycle order and the component unmounting is also kept deferred.
Tests and linting
pnpm test
and lint the project withpnpm lint