fix: store style

Author: btea

Diff for: packages/runtime-dom/src/modules/style.ts

@@ -1,5 +1,5 @@
 import { isString, hyphenate, capitalize, isArray } from '@vue/shared'
-import { camelize, isProxy } from '@vue/runtime-core'
+import { camelize } from '@vue/runtime-core'
 
 type Style = string | Record<string, string | string[]> | null
 
@@ -8,12 +8,7 @@ export function patchStyle(el: Element, prev: Style, next: Style) {
   const isCssString = isString(next)
   if (next && !isCssString) {
     for (const key in next) {
-      if (
-        !isProxy(next) &&
-        prev &&
-        !isString(prev) &&
-        prev[key] === next[key]
-      ) {
+      if (prev && !isString(prev) && prev[key] === next[key]) {
         continue
       }
       setStyle(style, key, next[key])

Diff for: packages/shared/src/normalizeProp.ts

@@ -1,4 +1,4 @@
-import { isArray, isString, isObject, hyphenate } from './'
+import { isArray, isString, isObject, hyphenate, extend } from './'
 import { isNoUnitNumericStyleProp } from './domAttrConfig'
 
 export type NormalizedStyle = Record<string, string | number>
@@ -23,7 +23,10 @@ export function normalizeStyle(
   } else if (isString(value)) {
     return value
   } else if (isObject(value)) {
-    return value
+    // store normalized style under a different key for next diff
+    // make sure to clone it if it's reactive, since the user likely wants
+    // to mutate it.
+    return extend({}, value)
   }
 }