From 405170f5e6092fae30f829bea59f46174dc60650 Mon Sep 17 00:00:00 2001
From: neverland <chenjiahan@youzan.com>
Date: Sun, 8 Aug 2021 17:42:51 +0800
Subject: [PATCH] fix(Field): textarea scroll to top after resizing (#9207)

---
 src/field/index.js | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/field/index.js b/src/field/index.js
index ce4743318..8084445a7 100644
--- a/src/field/index.js
+++ b/src/field/index.js
@@ -2,6 +2,7 @@
 import { resetScroll } from '../utils/dom/reset-scroll';
 import { formatNumber } from '../utils/format/number';
 import { preventDefault } from '../utils/dom/event';
+import { getRootScrollTop, setRootScrollTop } from '../utils/dom/scroll';
 import {
   isDef,
   addUnit,
@@ -347,7 +348,7 @@ export default createComponent({
       this.focused = true;
       this.$emit('focus', event);
 
-      // readonly not work in lagacy mobile safari
+      // readonly not work in legacy mobile safari
       /* istanbul ignore if */
       const readonly = this.getProp('readonly');
       if (readonly) {
@@ -409,6 +410,7 @@ export default createComponent({
         return;
       }
 
+      const scrollTop = getRootScrollTop();
       input.style.height = 'auto';
 
       let height = input.scrollHeight;
@@ -424,6 +426,8 @@ export default createComponent({
 
       if (height) {
         input.style.height = height + 'px';
+        // https://github.com/youzan/vant/issues/9178
+        setRootScrollTop(scrollTop);
       }
     },
 
@@ -475,8 +479,8 @@ export default createComponent({
       let inputType = type;
       let inputMode;
 
-      // type="number" is weired in iOS, and can't prevent dot in Android
-      // so use inputmode to set keyboard in mordern browers
+      // type="number" is weird in iOS, and can't prevent dot in Android
+      // so use inputmode to set keyboard in modern browsers
       if (type === 'number') {
         inputType = 'text';
         inputMode = 'decimal';