Prevent Svelte unsafe state mutation in subscription #985
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On initial load when a query collection tries to start up, and there's local data to hydrate from the queryPersister, it would throw https://svelte.dev/docs/svelte/runtime-errors#Client-errors-state_unsafe_mutation. I don't particularly like adding `await tick()`, but when added here to `useLiveQuery()` it does seem to solve the issue here. Claude said > When subscribeChanges is called with includeInitialState: true, it fires the callback synchronously with the initial data - right there during the $effect setup. > At that moment, Svelte might still be in the middle of a render cycle (evaluating $derived, rendering templates, etc.). Updating $state during render is forbidden - hence state_unsafe_mutation. > Without tick(): $effect runs → subscribeChanges → callback fires immediately → state mutation → ERROR (still rendering) > With tick(): $effect runs → subscribeChanges → callback fires → await tick() → [render completes] → state mutation → OK
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On initial load when a query collection tries to start up, AND there's local data to hydrate from the queryPersister, it would throw https://svelte.dev/docs/svelte/runtime-errors#Client-errors-state_unsafe_mutation.
🎯 Changes
I don't particularly like adding
await tick(), but when added here to the subscribeChanges() insideuseLiveQuery()it does seem to patch the issue.Claude said:
✅ Checklist
pnpm test:pr.🚀 Release Impact