@tanstack/virtual-core - npm Package Compare versions

Comparing version 3.17.2 to 3.17.3

dist/cjs/index.cjs

@@ -423,3 +423,4 @@ "use strict";
             this.scrollAdjustments = 0;
-            this.scrollDirection = isScrolling ? this.getScrollOffset() < offset ? "forward" : "backward" : null;
+            const prevOffset = this.getScrollOffset();
+            this.scrollDirection = isScrolling ? prevOffset === offset ? this.scrollDirection : prevOffset < offset ? "forward" : "backward" : null;
             this.scrollOffset = offset;
@@ -722,3 +723,7 @@ this.isScrolling = isScrolling;
       (measurements, outerSize, scrollOffset, lanes) => {
-        return this.range = measurements.length > 0 && outerSize > 0 ? calculateRange({
+        if (measurements.length === 0 || outerSize === 0) {
+          this.range = null;
+          return null;
+        }
+        this.range = calculateRangeImpl(
           measurements,
@@ -728,7 +733,7 @@ outerSize,
           lanes,
-          // Pass the typed array so binary search + forward-walk can
-          // read start/end directly from Float64Array, skipping the
-          // Proxy traps that materialize a full VirtualItem per probe.
-          flat: lanes === 1 && this._flatMeasurements != null ? this._flatMeasurements : null
-        }) : null;
+          // Pass the typed array so binary search + forward-walk can read
+          // start/end directly from Float64Array, skipping the Proxy traps.
+          lanes === 1 && this._flatMeasurements != null ? this._flatMeasurements : null
+        );
+        return this.range;
       },
@@ -1193,22 +1198,40 @@ {
 };
-function calculateRange({
-  measurements,
-  outerSize,
-  scrollOffset,
-  lanes,
-  flat
-}) {
+function findNearestBinarySearchFlat(flat, high, value) {
+  let low = 0;
+  while (low <= high) {
+    const middle = (low + high) / 2 | 0;
+    const currentValue = flat[middle * 2];
+    if (currentValue < value) {
+      low = middle + 1;
+    } else if (currentValue > value) {
+      high = middle - 1;
+    } else {
+      return middle;
+    }
+  }
+  return low > 0 ? low - 1 : 0;
+}
+function calculateRangeImpl(measurements, outerSize, scrollOffset, lanes, flat) {
   const lastIndex = measurements.length - 1;
-  const getStart = flat ? (index) => flat[index * 2] : (index) => measurements[index].start;
-  const getEnd = flat ? (index) => flat[index * 2] + flat[index * 2 + 1] : (index) => measurements[index].end;
   if (measurements.length <= lanes) {
-    return {
-      startIndex: 0,
-      endIndex: lastIndex
-    };
+    return { startIndex: 0, endIndex: lastIndex };
   }
+  if (lanes === 1 && flat !== null) {
+    const startIndex2 = findNearestBinarySearchFlat(
+      flat,
+      lastIndex,
+      scrollOffset
+    );
+    let endIndex2 = startIndex2;
+    const limit = scrollOffset + outerSize;
+    while (endIndex2 < lastIndex && flat[endIndex2 * 2] + flat[endIndex2 * 2 + 1] < limit) {
+      endIndex2++;
+    }
+    return { startIndex: startIndex2, endIndex: endIndex2 };
+  }
+  const getStart = (index) => measurements[index].start;
   let startIndex = findNearestBinarySearch(0, lastIndex, getStart, scrollOffset);
   let endIndex = startIndex;
   if (lanes === 1) {
-    while (endIndex < lastIndex && getEnd(endIndex) < scrollOffset + outerSize) {
+    while (endIndex < lastIndex && measurements[endIndex].end < scrollOffset + outerSize) {
       endIndex++;
@@ -1215,0 +1238,0 @@ }

dist/esm/index.js

@@ -421,3 +421,4 @@ import { createLazyMeasurementsView } from "./lazy-measurements.js";
             this.scrollAdjustments = 0;
-            this.scrollDirection = isScrolling ? this.getScrollOffset() < offset ? "forward" : "backward" : null;
+            const prevOffset = this.getScrollOffset();
+            this.scrollDirection = isScrolling ? prevOffset === offset ? this.scrollDirection : prevOffset < offset ? "forward" : "backward" : null;
             this.scrollOffset = offset;
@@ -720,3 +721,7 @@ this.isScrolling = isScrolling;
       (measurements, outerSize, scrollOffset, lanes) => {
-        return this.range = measurements.length > 0 && outerSize > 0 ? calculateRange({
+        if (measurements.length === 0 || outerSize === 0) {
+          this.range = null;
+          return null;
+        }
+        this.range = calculateRangeImpl(
           measurements,
@@ -726,7 +731,7 @@ outerSize,
           lanes,
-          // Pass the typed array so binary search + forward-walk can
-          // read start/end directly from Float64Array, skipping the
-          // Proxy traps that materialize a full VirtualItem per probe.
-          flat: lanes === 1 && this._flatMeasurements != null ? this._flatMeasurements : null
-        }) : null;
+          // Pass the typed array so binary search + forward-walk can read
+          // start/end directly from Float64Array, skipping the Proxy traps.
+          lanes === 1 && this._flatMeasurements != null ? this._flatMeasurements : null
+        );
+        return this.range;
       },
@@ -1191,22 +1196,40 @@ {
 };
-function calculateRange({
-  measurements,
-  outerSize,
-  scrollOffset,
-  lanes,
-  flat
-}) {
+function findNearestBinarySearchFlat(flat, high, value) {
+  let low = 0;
+  while (low <= high) {
+    const middle = (low + high) / 2 | 0;
+    const currentValue = flat[middle * 2];
+    if (currentValue < value) {
+      low = middle + 1;
+    } else if (currentValue > value) {
+      high = middle - 1;
+    } else {
+      return middle;
+    }
+  }
+  return low > 0 ? low - 1 : 0;
+}
+function calculateRangeImpl(measurements, outerSize, scrollOffset, lanes, flat) {
   const lastIndex = measurements.length - 1;
-  const getStart = flat ? (index) => flat[index * 2] : (index) => measurements[index].start;
-  const getEnd = flat ? (index) => flat[index * 2] + flat[index * 2 + 1] : (index) => measurements[index].end;
   if (measurements.length <= lanes) {
-    return {
-      startIndex: 0,
-      endIndex: lastIndex
-    };
+    return { startIndex: 0, endIndex: lastIndex };
   }
+  if (lanes === 1 && flat !== null) {
+    const startIndex2 = findNearestBinarySearchFlat(
+      flat,
+      lastIndex,
+      scrollOffset
+    );
+    let endIndex2 = startIndex2;
+    const limit = scrollOffset + outerSize;
+    while (endIndex2 < lastIndex && flat[endIndex2 * 2] + flat[endIndex2 * 2 + 1] < limit) {
+      endIndex2++;
+    }
+    return { startIndex: startIndex2, endIndex: endIndex2 };
+  }
+  const getStart = (index) => measurements[index].start;
   let startIndex = findNearestBinarySearch(0, lastIndex, getStart, scrollOffset);
   let endIndex = startIndex;
   if (lanes === 1) {
-    while (endIndex < lastIndex && getEnd(endIndex) < scrollOffset + outerSize) {
+    while (endIndex < lastIndex && measurements[endIndex].end < scrollOffset + outerSize) {
       endIndex++;
@@ -1213,0 +1236,0 @@ }

package.json

 {
   "name": "@tanstack/virtual-core",
-  "version": "3.17.2",
+  "version": "3.17.3",
   "description": "Headless UI for virtualizing scrollable elements in TS/JS + Frameworks",
@@ -5,0 +5,0 @@ "author": "Tanner Linsley",

No alert changes

Improved metrics

Total package byte prevSize

389311

1.42%

Lines of code

4884

1.58%

No dependency changes