wip: refactor parentChain management

packages/renderer-dom/src/index.ts

@@ -1,4 +1,4 @@
-import { createRenderer, VNode } from '@vue/core'
+import { createRenderer, VNode, ComponentInstance } from '@vue/core'
 import { nodeOps } from './nodeOps'
 import { patchData } from './patchData'
 import { teardownVNode } from './teardownVNode'
@@ -9,7 +9,10 @@ const { render: _render } = createRenderer({
   teardownVNode
 })
 
-type publicRender = (node: VNode | null, container: HTMLElement) => void
+type publicRender = (
+  node: VNode | null,
+  container: HTMLElement
+) => ComponentInstance | null
 export const render = _render as publicRender
 
 // re-export everything from core