perf(forms): avoid scheduling change detection on blur when already touched#68636
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arturovt wants to merge 1 commit into
Open
perf(forms): avoid scheduling change detection on blur when already touched#68636arturovt wants to merge 1 commit into
arturovt wants to merge 1 commit into
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JeanMeche
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May 10, 2026
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The blur listener on native form controls was registered through
`host.listenToDom('blur', ...)`, which wraps the callback with `wrapListener`.
`wrapListener` always calls `markViewDirty` before running the callback,
triggering change detection on every blur event.
When a control is already touched, calling `markAsTouched()` again is a no-op.
Signals skip updates for equal values, so no reactive notification or change
detection should happen.
Fix this by registering the blur listener with `addEventListener` directly,
bypassing `wrapListener`. When the control becomes touched for the first time,
the signal write still schedules change detection. Subsequent blur events on an
already-touched control no longer trigger unnecessary CD cycles.
A regression test verifies that `ChangeDetectionScheduler.notify()` is not
called when blur fires on an already-touched control.
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The blur listener on native form controls was registered through
host.listenToDom('blur', ...), which wraps the callback withwrapListener.wrapListeneralways callsmarkViewDirtybefore running the callback, triggering change detection on every blur event.When a control is already touched, calling
markAsTouched()again is a no-op. Signals skip updates for equal values, so no reactive notification or change detection should happen.Fix this by registering the blur listener with
addEventListenerdirectly, bypassingwrapListener. When the control becomes touched for the first time, the signal write still schedules change detection. Subsequent blur events on an already-touched control no longer trigger unnecessary CD cycles.A regression test verifies that
ChangeDetectionScheduler.notify()is not called when blur fires on an already-touched control.