fix(runtime-core): avoid setting direct ref of useTemplateRef in dev

packages/runtime-core/__tests__/helpers/useTemplateRef.spec.ts

@@ -106,6 +106,134 @@ describe('useTemplateRef', () => {
     expect(tRef!.value).toBe(null)
   })
 
+  test('should work when used with direct ref value with ref_key', () => {
+    let tRef: ShallowRef
+    const key = 'refKey'
+    const Comp = {
+      setup() {
+        tRef = useTemplateRef(key)
+        return () => h('div', { ref: tRef, ref_key: key })
+      },
+    }
+    const root = nodeOps.createElement('div')
+    render(h(Comp), root)
+
+    expect('target is readonly').not.toHaveBeenWarned()
+    expect(tRef!.value).toBe(root.children[0])
+  })
+
+  test('should work when used with direct ref value with ref_key and ref_for', () => {
+    let tRef: ShallowRef
+    const key = 'refKey'
+    const Comp = {
+      setup() {
+        tRef = useTemplateRef(key)
+      },
+      render() {
+        return h(
+          'div',
+          [1, 2, 3].map(x =>
+            h('span', { ref: tRef, ref_key: key, ref_for: true }, x.toString()),
+          ),
+        )
+      },
+    }
+    const root = nodeOps.createElement('div')
+    render(h(Comp), root)
+
+    expect('target is readonly').not.toHaveBeenWarned()
+    expect(tRef!.value).toHaveLength(3)
+  })
+
+  test('should work when used with direct ref value with ref_key and dynamic value', async () => {
+    const refMode = ref('h1-ref')
+
+    let tRef: ShallowRef
+    const key = 'refKey'
+
+    const Comp = {
+      setup() {
+        tRef = useTemplateRef(key)
+      },
+      render() {
+        switch (refMode.value) {
+          case 'h1-ref':
+            return h('h1', { ref: tRef, ref_key: key })
+          case 'h2-ref':
+            return h('h2', { ref: tRef, ref_key: key })
+          case 'no-ref':
+            return h('span')
+          case 'nothing':
+            return null
+        }
+      },
+    }
+
+    const root = nodeOps.createElement('div')
+    render(h(Comp), root)
+
+    expect(tRef!.value.tag).toBe('h1')
+
+    refMode.value = 'h2-ref'
+    await nextTick()
+    expect(tRef!.value.tag).toBe('h2')
+
+    refMode.value = 'no-ref'
+    await nextTick()
+    expect(tRef!.value).toBeNull()
+
+    refMode.value = 'nothing'
+    await nextTick()
+    expect(tRef!.value).toBeNull()
+
+    expect('target is readonly').not.toHaveBeenWarned()
+  })
+
+  test('should work when used with dynamic direct refs and ref_keys', async () => {
+    const refKey = ref('foo')
+
+    let tRefs: Record<string, ShallowRef>
+
+    const Comp = {
+      setup() {
+        tRefs = {
+          foo: useTemplateRef('foo'),
+          bar: useTemplateRef('bar'),
+        }
+      },
+      render() {
+        return h('div', { ref: tRefs[refKey.value], ref_key: refKey.value })
+      },
+    }
+
+    const root = nodeOps.createElement('div')
+    render(h(Comp), root)
+
+    expect(tRefs!['foo'].value).toBe(root.children[0])
+    expect(tRefs!['bar'].value).toBeNull()
+
+    refKey.value = 'bar'
+    await nextTick()
+    expect(tRefs!['foo'].value).toBeNull()
+    expect(tRefs!['bar'].value).toBe(root.children[0])
+
+    expect('target is readonly').not.toHaveBeenWarned()
+  })
+
+  test('should not work when used with direct ref value without ref_key (in dev mode)', () => {
+    let tRef: ShallowRef
+    const Comp = {
+      setup() {
+        tRef = useTemplateRef('refKey')
+        return () => h('div', { ref: tRef })
+      },
+    }
+    const root = nodeOps.createElement('div')
+    render(h(Comp), root)
+
+    expect(tRef!.value).toBeNull()
+  })
+
   test('should work when used as direct ref value (compiled in prod mode)', () => {
     __DEV__ = false
     try {

packages/runtime-core/src/rendererTemplateRef.ts

@@ -1,5 +1,10 @@
 import type { SuspenseBoundary } from './components/Suspense'
-import type { VNode, VNodeNormalizedRef, VNodeNormalizedRefAtom } from './vnode'
+import type {
+  VNode,
+  VNodeNormalizedRef,
+  VNodeNormalizedRefAtom,
+  VNodeRef,
+} from './vnode'
 import {
   EMPTY_OBJ,
   ShapeFlags,
@@ -94,6 +99,10 @@ export function setRef(
           return hasOwn(rawSetupState, key)
         }
 
+  const canSetRef = (ref: VNodeRef) => {
+    return !__DEV__ || !knownTemplateRefs.has(ref as any)
+  }
+
   // dynamic ref changed. unset old ref
   if (oldRef != null && oldRef !== ref) {
     if (isString(oldRef)) {
@@ -102,7 +111,13 @@ export function setRef(
         setupState[oldRef] = null
       }
     } else if (isRef(oldRef)) {
-      oldRef.value = null
+      if (canSetRef(oldRef)) {
+        oldRef.value = null
+      }
+
+      // this type assertion is valid since `oldRef` has already been asserted to be non-null
+      const oldRawRefAtom = oldRawRef as VNodeNormalizedRefAtom
+      if (oldRawRefAtom.k) refs[oldRawRefAtom.k] = null
     }
   }
 
@@ -119,7 +134,9 @@ export function setRef(
             ? canSetSetupRef(ref)
               ? setupState[ref]
               : refs[ref]
-            : ref.value
+            : canSetRef(ref) || !rawRef.k
+              ? ref.value
+              : refs[rawRef.k]
           if (isUnmount) {
             isArray(existing) && remove(existing, refValue)
           } else {
@@ -130,8 +147,11 @@ export function setRef(
                   setupState[ref] = refs[ref]
                 }
               } else {
-                ref.value = [refValue]
-                if (rawRef.k) refs[rawRef.k] = ref.value
+                const newVal = [refValue]
+                if (canSetRef(ref)) {
+                  ref.value = newVal
+                }
+                if (rawRef.k) refs[rawRef.k] = newVal
               }
             } else if (!existing.includes(refValue)) {
               existing.push(refValue)
@@ -143,7 +163,9 @@ export function setRef(
             setupState[ref] = value
           }
         } else if (_isRef) {
-          ref.value = value
+          if (canSetRef(ref)) {
+            ref.value = value
+          }
           if (rawRef.k) refs[rawRef.k] = value
         } else if (__DEV__) {
           warn('Invalid template ref type:', ref, `(${typeof ref})`)