perf(guard): Add a tool function to handle the logic of TargetRouterV…

src/composables/guards.js

@@ -1,5 +1,5 @@
 import { getCurrentInstance, onUnmounted } from 'vue'
-import { throwNoCurrentInstance } from './utils'
+import { throwNoCurrentInstance, getTargetRouterViewDepth } from './utils'
 import { useRouter } from './globals'
 
 export function onBeforeRouteUpdate (guard) {
@@ -42,19 +42,12 @@ function useFilteredGuard (guard, fn) {
   let target = instance.proxy
   // find the nearest RouterView to know the depth
   while (
-    target &&
-    target.$vnode &&
-    target.$vnode.data &&
-    target.$vnode.data.routerViewDepth == null
+    getTargetRouterViewDepth(target)
   ) {
     target = target.$parent
   }
 
-  const depth =
-    target && target.$vnode && target.$vnode.data
-      ? target.$vnode.data.routerViewDepth
-      : null
-
+  const depth = getTargetRouterViewDepth(target)
   if (depth != null) {
     const removeGuard = router.beforeEach((to, from, next) => {
       return fn(to, from, depth) ? guard(to, from, next) : next()

src/util/route.js

@@ -149,3 +149,8 @@ export function handleRouteEntered (route: Route) {
     }
   }
 }
+
+export function getTargetRouterViewDepth (target: any) {
+  return target && target.$vnode && target.$vnode.data ? target.$vnode.data.routerViewDepth
+    : null
+}

types/router.d.ts

@@ -354,12 +354,13 @@ interface RouteConfigMultipleViews extends _RouteConfigBase {
 }
 
 export type RouteConfig = RouteConfigSingleView | RouteConfigMultipleViews
+export type VueInstance = Dictionary<Vue>
 
 export interface RouteRecord {
   path: string
   regex: RegExp
   components: Dictionary<Component>
-  instances: Dictionary<Vue>
+  instances: VueInstance
   name?: string
   parent?: RouteRecord
   redirect?: RedirectOption
@@ -380,7 +381,7 @@ export interface RouteRecord {
 export interface RouteRecordPublic {
   path: string
   components: Dictionary<Component>
-  instances: Dictionary<Vue>
+  instances: VueInstance
   name?: string
   redirect?: RedirectOption
   meta: any