perf: simplify clone

packages/compiler-ssr/src/transforms/ssrTransformComponent.ts

@@ -55,7 +55,7 @@ import {
   ssrProcessTransitionGroup,
   ssrTransformTransitionGroup,
 } from './ssrTransformTransitionGroup'
-import { extend, isArray, isObject, isSymbol } from '@vue/shared'
+import { extend, isArray, isObject, isPlainObject, isSymbol } from '@vue/shared'
 import { buildSSRProps } from './ssrTransformElement'
 import {
   ssrProcessTransition,
@@ -121,6 +121,8 @@ export const ssrTransformComponent: NodeTransform = (node, context) => {
   const vnodeBranches: ReturnStatement[] = []
   const clonedNode = clone(node)
 
+  console.log(clonedNode)
+
   return function ssrPostTransformComponent() {
     // Using the cloned node, build the normal VNode-based branches (for
     // fallback in case the child is render-fn based). Store them in an array
@@ -371,26 +373,12 @@ function subTransform(
 function clone(v: any): any {
   if (isArray(v)) {
     return v.map(clone)
-  } else if (isObject(v)) {
-    if (v instanceof Map) {
-      const res = new Map()
-      v.forEach((value: any, key: any) => {
-        res.set(clone(key), clone(value))
-      })
-      return res
-    } else if (v instanceof Set) {
-      const res = new Set()
-      v.forEach((value: any) => {
-        res.add(clone(value))
-      })
-      return res
-    } else {
-      const res: any = {}
-      for (const key in v) {
-        res[key] = clone(v[key])
-      }
-      return res
+  } else if (isPlainObject(v)) {
+    const res: any = {}
+    for (const key in v) {
+      res[key] = clone(v[key as keyof typeof v])
     }
+    return res
   } else {
     return v
   }