fix(VAutocomplete): fix scroll jump #22531

packages/vuetify/src/components/VAutocomplete/VAutocomplete.tsx

@@ -436,9 +436,11 @@ export const VAutocomplete = genericComponent<new <
         const index = displayItems.value.findIndex(
           item => model.value.some(s => item.value === s.value)
         )
-        IN_BROWSER && window.requestAnimationFrame(() => {
-          index >= 0 && vVirtualScrollRef.value?.scrollToIndex(index)
-        })
+        if (index >= 0 && IN_BROWSER) {
+          window.requestAnimationFrame(() => {
+            vVirtualScrollRef.value?.scrollToIndex(index)
+          })
+        }
       }
       if (val) _searchLock.value = null
     })

packages/vuetify/src/composables/virtual.ts

@@ -96,8 +96,6 @@ export function useVirtual <T> (props: VirtualProps, items: Ref<readonly T[]>) {
 
   const unwatch = watch(hasInitialRender, v => {
     if (!v) return
-    // First render is complete, update offsets and visible
-    // items in case our assumed item height was incorrect
 
     unwatch()
     markerOffset = markerRef.value!.offsetTop
@@ -122,7 +120,7 @@ export function useVirtual <T> (props: VirtualProps, items: Ref<readonly T[]>) {
     const prevHeight = sizes[index]
     const prevMinHeight = itemHeight.value
 
-    itemHeight.value = prevMinHeight ? Math.min(itemHeight.value, height) : height
+    itemHeight.value = prevMinHeight ? itemHeight.value : height
 
     if (prevHeight !== height || prevMinHeight !== itemHeight.value) {
       sizes[index] = height
@@ -167,10 +165,9 @@ export function useVirtual <T> (props: VirtualProps, items: Ref<readonly T[]>) {
     const scrollDeltaT = scrollTime - lastScrollTime
 
     if (scrollDeltaT > 500) {
-      scrollVelocity = Math.sign(scrollTop - lastScrollTop)
-
-      // Not super important, only update at the
-      // start of a scroll sequence to avoid reflows
+      // FIX: use 0 instead of Math.sign to ensure both first and last
+      // are updated correctly after a long pause (e.g. after programmatic scroll)
+      scrollVelocity = 0
       markerOffset = markerRef.value.offsetTop
     } else {
       scrollVelocity = scrollTop - lastScrollTop
@@ -184,6 +181,7 @@ export function useVirtual <T> (props: VirtualProps, items: Ref<readonly T[]>) {
 
     calculateVisibleItems()
   }
+
   function handleScrollend () {
     if (!containerRef.value || !markerRef.value) return
 
@@ -224,7 +222,6 @@ export function useVirtual <T> (props: VirtualProps, items: Ref<readonly T[]>) {
         first.value = start
         last.value = end
       } else {
-        // Only update the side that's reached its limit if there's still buffer left
         if (start <= 0) first.value = start
         if (end >= items.value.length) last.value = end
       }
@@ -236,10 +233,17 @@ export function useVirtual <T> (props: VirtualProps, items: Ref<readonly T[]>) {
 
   function scrollToIndex (index: number) {
     const offset = calculateOffset(index)
+
     if (!containerRef.value || (index && !offset)) {
       targetScrollIndex = index
     } else {
       containerRef.value.scrollTop = offset
+      lastScrollTop = offset
+      scrollVelocity = 0
+      lastScrollTime = performance.now()
+      targetScrollIndex = -1
+      cancelAnimationFrame(raf)
+      _calculateVisibleItems()
     }
   }