refactor(runtime-core): extract common getComponentName function (#2454)

packages/runtime-core/src/components/KeepAlive.ts

@@ -1,11 +1,11 @@
 import {
   ConcreteComponent,
   getCurrentInstance,
-  FunctionalComponent,
   SetupContext,
   ComponentInternalInstance,
   LifecycleHooks,
-  currentInstance
+  currentInstance,
+  getComponentName
 } from '../component'
 import { VNode, cloneVNode, isVNode, VNodeProps } from '../vnode'
 import { warn } from '../warning'
@@ -151,7 +151,7 @@ const KeepAliveImpl = {
 
     function pruneCache(filter?: (name: string) => boolean) {
       cache.forEach((vnode, key) => {
-        const name = getName(vnode.type as ConcreteComponent)
+        const name = getComponentName(vnode.type as ConcreteComponent)
         if (name && (!filter || !filter(name))) {
           pruneCacheEntry(key)
         }
@@ -235,7 +235,7 @@ const KeepAliveImpl = {
 
       let vnode = getInnerChild(rawVNode)
       const comp = vnode.type as ConcreteComponent
-      const name = getName(comp)
+      const name = getComponentName(comp)
       const { include, exclude, max } = props
 
       if (
@@ -301,10 +301,6 @@ export const KeepAlive = (KeepAliveImpl as any) as {
   }
 }
 
-function getName(comp: ConcreteComponent): string | void {
-  return (comp as FunctionalComponent).displayName || comp.name
-}
-
 function matches(pattern: MatchPattern, name: string): boolean {
   if (isArray(pattern)) {
     return pattern.some((p: string | RegExp) => matches(p, name))