fix: coalesce scan() into a single rAF to avoid paint delay on bulk DOM mutations#344
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fix: coalesce scan() into a single rAF to avoid paint delay on bulk DOM mutations#344
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…OM mutations Replace per-element WeakMap+rAF deduplication with a shared Set of pending elements and a single requestAnimationFrame timer. When many elements are added in one frame (e.g. framework list rendering), only one rAF callback now runs before paint instead of one per element. Fixes #343 Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Summary
Fixes #343
When many elements are added to the DOM in a single frame (e.g. a framework rendering a list), the
scan()function inlazy-define.tswas scheduling a separaterequestAnimationFramecallback for each element. Since all rAF callbacks run before the browser paints, this delayed the first paint proportionally to the number of added elements.Changes
Replaced the per-element
WeakMap+requestAnimationFramededuplication with:Set<ElementLike>that collects pending elementsrequestAnimationFrametimer that processes all pending elements in one callbackThis ensures that no matter how many elements are added in a single frame, only one rAF callback runs before paint.
Testing
Added a test that verifies multiple elements added at once are coalesced into minimal rAF calls rather than one per element. All existing tests continue to pass.