From fc983516f3f16ff54468bb3ba7941f80b5312fc7 Mon Sep 17 00:00:00 2001
From: daiwei <daiwei521@126.com>
Date: Tue, 9 Dec 2025 15:12:47 +0800
Subject: [PATCH 1/2] fix(hmr): handle reload for template-only components
 switching between vapor and vdom

---
 packages/runtime-core/src/hmr.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/runtime-core/src/hmr.ts b/packages/runtime-core/src/hmr.ts
index 1d35bd34692..2c5cc54fa64 100644
--- a/packages/runtime-core/src/hmr.ts
+++ b/packages/runtime-core/src/hmr.ts
@@ -117,13 +117,14 @@ function reload(id: string, newComp: HMRComponent): void {
   if (!record) return
 
   newComp = normalizeClassComponent(newComp)
+  const isVapor = record.initialDef.__vapor
   // update initial def (for not-yet-rendered components)
   updateComponentDef(record.initialDef, newComp)
 
   // create a snapshot which avoids the set being mutated during updates
   const instances = [...record.instances]
 
-  if (newComp.__vapor && !instances.some(i => i.ceReload)) {
+  if (isVapor && newComp.__vapor && !instances.some(i => i.ceReload)) {
     // For multiple instances with the same __hmrId, remove styles first before reload
     // to avoid the second instance's style removal deleting the first instance's
     // newly added styles (since hmrReload is synchronous)

From 038e5a987003749ee21c57ca24d1b59018b27545 Mon Sep 17 00:00:00 2001
From: daiwei <daiwei521@126.com>
Date: Tue, 9 Dec 2025 16:49:40 +0800
Subject: [PATCH 2/2] fix(hmr): refactor scope cleanup to use reset method for
 stale effects management

---
 packages/reactivity/src/effectScope.ts     | 15 +++++++++++----
 packages/runtime-vapor/src/component.ts    |  3 +--
 packages/runtime-vapor/src/hmr.ts          |  6 ++----
 packages/runtime-vapor/src/renderEffect.ts |  4 ++--
 4 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/packages/reactivity/src/effectScope.ts b/packages/reactivity/src/effectScope.ts
index 36c9b85e8d7..105ca5a9d6a 100644
--- a/packages/reactivity/src/effectScope.ts
+++ b/packages/reactivity/src/effectScope.ts
@@ -73,6 +73,17 @@ export class EffectScope implements ReactiveNode {
       return
     }
     this.flags = EffectFlags.STOP
+    this.reset()
+    const sub = this.subs
+    if (sub !== undefined) {
+      unlink(sub)
+    }
+  }
+
+  /**
+   * @internal
+   */
+  reset(): void {
     let dep = this.deps
     while (dep !== undefined) {
       const node = dep.dep
@@ -83,10 +94,6 @@ export class EffectScope implements ReactiveNode {
         dep = unlink(dep, this)
       }
     }
-    const sub = this.subs
-    if (sub !== undefined) {
-      unlink(sub)
-    }
     cleanup(this)
   }
 }
diff --git a/packages/runtime-vapor/src/component.ts b/packages/runtime-vapor/src/component.ts
index c66e5f90d1c..cd920471b2c 100644
--- a/packages/runtime-vapor/src/component.ts
+++ b/packages/runtime-vapor/src/component.ts
@@ -592,8 +592,7 @@ export class VaporComponentInstance<
   asyncDep: Promise<any> | null
   asyncResolved: boolean
 
-  // for HMR and vapor custom element
-  // all render effects associated with this instance
+  // for vapor custom element
   renderEffects?: RenderEffect[]
 
   hasFallthrough: boolean
diff --git a/packages/runtime-vapor/src/hmr.ts b/packages/runtime-vapor/src/hmr.ts
index f045595b548..521cc6ae6c8 100644
--- a/packages/runtime-vapor/src/hmr.ts
+++ b/packages/runtime-vapor/src/hmr.ts
@@ -19,12 +19,10 @@ export function hmrRerender(instance: VaporComponentInstance): void {
   const normalized = normalizeBlock(instance.block)
   const parent = normalized[0].parentNode!
   const anchor = normalized[normalized.length - 1].nextSibling
+  // reset scope to avoid stale effects
+  instance.scope.reset()
   remove(instance.block, parent)
   const prev = setCurrentInstance(instance)
-  if (instance.renderEffects) {
-    instance.renderEffects.forEach(e => e.stop())
-    instance.renderEffects = []
-  }
   pushWarningContext(instance)
   devRender(instance)
   popWarningContext()
diff --git a/packages/runtime-vapor/src/renderEffect.ts b/packages/runtime-vapor/src/renderEffect.ts
index ce8eaf46afd..08f12614210 100644
--- a/packages/runtime-vapor/src/renderEffect.ts
+++ b/packages/runtime-vapor/src/renderEffect.ts
@@ -44,8 +44,8 @@ export class RenderEffect extends ReactiveEffect {
           : void 0
       }
 
-      if (__DEV__ || instance.type.ce) {
-        // register effect for stopping them during HMR rerender
+      // register effect for vapor custom element update
+      if (instance.type.ce) {
         ;(instance.renderEffects || (instance.renderEffects = [])).push(this)
       }
       job.i = instance