fix: resolve SSR hydration ordinal drift from structural blocks#216
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mohamedmansour merged 2 commits intomainfrom Apr 10, 2026
Merged
fix: resolve SSR hydration ordinal drift from structural blocks#216mohamedmansour merged 2 commits intomainfrom
mohamedmansour merged 2 commits intomainfrom
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and count element/text ordinals to map compiled template paths to SSR DOM nodes. When conditional (<if>) or repeat (<for>) blocks render content into the SSR DOM, the extra nodes shift ordinals so later siblings resolve to the wrong element. Root cause: the compiled template static HTML (meta.h) strips structural blocks, but the SSR DOM contains them inline between marker pairs (<!--wc-->...<!--/wc--> and <!--wr-->...<!--/wr-->). The ordinal counting did not account for these extra ranges. This manifested in the commerce app when navigating from a zero-result search page (/search?q=test) to a category: the <for> loop's parent container resolved to the <p> no-results message instead of <div class=grid>, leaving the product grid empty after SPA navigation. Framework changes (webui-framework): - Extract findByOrdinal() into markers.ts — walks parent children counting only nodes outside structural block marker pairs, with depth tracking for nested blocks of the same type. Both (element ordinals) and (text ordinals) now delegate to this single function. - Defer SSR marker removal — closing markers (<!--/wc-->, <!--/wr-->) and item markers (<!--wi-->) are collected during hydration but only removed after all path-based resolution is complete (after for events/refs). This ensures marker pairs are intact whenever findByOrdinal needs to skip structural blocks, regardless of hydration phase ordering. - Add 10 unit tests for findByOrdinal covering: conditional skipping, repeat skipping, nested conditionals, multiple sequential blocks, empty blocks, text ordinal drift, interleaved block types, and edge cases (empty parent, out-of-range ordinal). Commerce app changes: - Fix mp-category-nav @attr mode — change all-active from string mode (default '') to boolean mode (default false). String mode produced '' (falsy) from the boolean attribute, causing a hydration mismatch where the server-rendered <if condition=allActive> block was not tracked by the client, leaving orphaned 'All' DOM nodes visible after SPA navigation. - Fix Related Products scrollbar visibility — the scrollbar thumb used --webui-border (#262626), the same color as the track (--webui-surface #262626), making it invisible. Changed to --webui-text-muted and added scrollbar-width/scrollbar-color for Firefox cross-browser support. - Add regression test for search→category SPA navigation verifying category nav state and product grid population. - Update visual regression snapshots. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
akroshg
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Apr 10, 2026
akroshg
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Apr 10, 2026
akroshg
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Apr 10, 2026
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Compiled template paths to SSR DOM nodes. When conditional () or repeat () blocks render content into the SSR DOM, the extra nodes shift ordinals so later siblings resolve to the wrong element.
Root cause: the compiled template static HTML (meta.h) strips structural blocks, but the SSR DOM contains them inline between marker pairs (... and ...). The ordinal counting did not account for these extra ranges.
This manifested in the commerce app when navigating from a zero-result search page (/search?q=test) to a category: the loop's parent container resolved to the
no-results message instead of
Framework changes (webui-framework):
Extract findByOrdinal() into markers.ts — walks parent children counting only nodes outside structural block marker pairs, with depth tracking for nested blocks of the same type. Both (element ordinals) and (text ordinals) now delegate to this single function.
Defer SSR marker removal — closing markers (, ) and item markers () are collected during hydration but only removed after all path-based resolution is complete (after for events/refs). This ensures marker pairs are intact whenever findByOrdinal needs to skip structural blocks, regardless of hydration phase ordering.
Add 10 unit tests for findByOrdinal covering: conditional skipping, repeat skipping, nested conditionals, multiple sequential blocks, empty blocks, text ordinal drift, interleaved block types, and edge cases (empty parent, out-of-range ordinal).
Commerce app changes:
Fix mp-category-nav @attr mode — change all-active from string mode (default '') to boolean mode (default false). String mode produced '' (falsy) from the boolean attribute, causing a hydration mismatch where the server-rendered block was not tracked by the client, leaving orphaned 'All' DOM nodes visible after SPA navigation.
Fix Related Products scrollbar visibility — the scrollbar thumb used --webui-border (#262626), the same color as the track (--webui-surface #262626), making it invisible. Changed to --webui-text-muted and added scrollbar-width/scrollbar-color for Firefox cross-browser support.
Add regression test for search→category SPA navigation verifying category nav state and product grid population.