Function resolveAsyncComponentPlaceholder

packages/runtime-core/src/renderer.ts:2627–2639

(anchorVnode: VNode)

}

function resolveAsyncComponentPlaceholder(anchorVnode: VNode) {
  if (anchorVnode.placeholder) {
    return anchorVnode.placeholder
  }

  // anchor vnode maybe is a wrapper component has single unresolved async component
  const instance = anchorVnode.component
  if (instance) {
    return resolveAsyncComponentPlaceholder(instance.subTree)
  }

  return null
}