fix(framework): trust SSR conditional content during hydration#286
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When hydrating a conditional block, the framework previously required the runtime condition value to be truthy before wiring up SSR content. This caused duplicate DOM when a condition depended on complex properties (like :data) set by the parent AFTER the child hydrates: 1. SSR renders content (condition was true on server) 2. Child hydrates — complex prop not yet set — condition evaluates false 3. SSR DOM nodes left orphaned (not wired, not removed) 4. Parent sets complex prop — condition becomes true — new nodes created 5. Result: duplicate content visible to the user Fix: during SSR hydration, if a <!--wc--> marker has content after it (the server rendered the block), hydrate that content regardless of the current condition value. The server was authoritative; the data will arrive from the parent and the condition will reconcile correctly. Added \() helper to detect SSR content between conditional markers. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…plex props Extends the complex-prop fixture with a test-cond-child component that has a conditional block driven by :data.showHeader. Three tests verify: - SSR conditional content is hydrated without duplicates (the core regression: child hydrates before parent sets :data, condition evaluates false, but SSR content must be preserved) - SSR conditional text matches the state.json value - Toggling :data.showHeader to false correctly removes the block Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
During SSR hydration, $hydrateCondContent was calling $updateInstance which evaluated text bindings with stale/missing data. When a child component's conditional block depended on a complex property (:data) from a parent that hadn't hydrated yet, the text nodes were overwritten from their correct SSR values to empty strings. Remove the $updateInstance calls from $hydrateCondContent — SSR text nodes already contain the correct server-rendered values. This is consistent with $mount which also skips $updateInstance for SSR roots. The bindings are wired and will update reactively once data arrives. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
akroshg
reviewed
May 8, 2026
| */ | ||
| private $hasContentAfterMarker(anchor: Comment, endData: string): boolean { | ||
| let sibling = anchor.nextSibling; | ||
| while (sibling) { |
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WE would loop only once, why while loop?
akroshg
approved these changes
May 8, 2026
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When hydrating a conditional block, the framework previously required the runtime condition value to be truthy before wiring up SSR content. This caused duplicate DOM when a condition depended on complex properties (like :data) set by the parent AFTER the child hydrates:
Fix: during SSR hydration, if a marker has content after it (the server rendered the block), hydrate that content regardless of the current condition value. The server was authoritative; the data will arrive from the parent and the condition will reconcile correctly.
Added helper to detect SSR content between conditional markers.