Function setRef

packages/runtime-core/src/rendererTemplateRef.ts:31–212

(
  rawRef: VNodeNormalizedRef,
  oldRawRef: VNodeNormalizedRef | null,
  parentSuspense: SuspenseBoundary | null,
  vnode: VNode,
  isUnmount = false,
)

 * Function for handling a template ref
 */
export function setRef(
  rawRef: VNodeNormalizedRef,
  oldRawRef: VNodeNormalizedRef | null,
  parentSuspense: SuspenseBoundary | null,
  vnode: VNode,
  isUnmount = false,
): void {
  if (isArray(rawRef)) {
    rawRef.forEach((r, i) =>
      setRef(
        r,
        oldRawRef && (isArray(oldRawRef) ? oldRawRef[i] : oldRawRef),
        parentSuspense,
        vnode,
        isUnmount,
      ),
    )
    return
  }

  if (isAsyncWrapper(vnode) && !isUnmount) {
    // #4999 if an async component already resolved and cached by KeepAlive,
    // we need to set the ref to inner component
    if (
      vnode.shapeFlag & ShapeFlags.COMPONENT_KEPT_ALIVE &&
      (vnode.type as ComponentOptions).__asyncResolved &&
      vnode.component!.subTree.component
    ) {
      setRef(rawRef, oldRawRef, parentSuspense, vnode.component!.subTree)
    }

    // otherwise, nothing needs to be done because the template ref
    // is forwarded to inner component
    return
  }

  const refValue =
    vnode.shapeFlag & ShapeFlags.STATEFUL_COMPONENT
      ? getComponentPublicInstance(vnode.component!)
      : vnode.el
  const value = isUnmount ? null : refValue

  const { i: owner, r: ref } = rawRef
  if (__DEV__ && !owner) {
    warn(
      `Missing ref owner context. ref cannot be used on hoisted vnodes. ` +
        `A vnode with ref must be created inside the render function.`,
    )
    return
  }
  const oldRef = oldRawRef && (oldRawRef as VNodeNormalizedRefAtom).r
  const refs = owner.refs === EMPTY_OBJ ? (owner.refs = {}) : owner.refs
  const setupState = owner.setupState
  const rawSetupState = toRaw(setupState)
  const canSetSetupRef =
    setupState === EMPTY_OBJ
      ? NO
      : (key: string) => {