From 8dec243dc1182c1db5d2928633bb446c7e94abd9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E4=B8=89=E5=92=B2=E6=99=BA=E5=AD=90=20Kevin=20Deng?=
 <sxzz@sxzz.moe>
Date: Sat, 3 Feb 2024 06:15:46 +0800
Subject: [PATCH] fix(reactivity): keep previous effect scope

---
 packages/reactivity/src/effectScope.ts |  4 +++-
 playground/src/v-for.js                | 12 ++++++++----
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/packages/reactivity/src/effectScope.ts b/packages/reactivity/src/effectScope.ts
index 6a3eaec9f..b101a4748 100644
--- a/packages/reactivity/src/effectScope.ts
+++ b/packages/reactivity/src/effectScope.ts
@@ -62,11 +62,13 @@ export class EffectScope {
     }
   }
 
+  prevScope: EffectScope | undefined
   /**
    * This should only be called on non-detached scopes
    * @internal
    */
   on() {
+    this.prevScope = activeEffectScope
     activeEffectScope = this
   }
 
@@ -75,7 +77,7 @@ export class EffectScope {
    * @internal
    */
   off() {
-    activeEffectScope = this.parent
+    activeEffectScope = this.prevScope
   }
 
   stop(fromParent?: boolean) {
diff --git a/playground/src/v-for.js b/playground/src/v-for.js
index e1ff1e1a8..b41e5976b 100644
--- a/playground/src/v-for.js
+++ b/playground/src/v-for.js
@@ -23,12 +23,16 @@ export default defineComponent({
           const container = document.createElement('li')
           append(container, node)
 
-          const update = () => {
+          renderEffect(() => {
             const [item, index] = block.s
             node.textContent = `${index}. ${item}`
-          }
-          renderEffect(update)
-          return [container, update]
+          })
+
+          renderEffect(() => {
+            const [item, index] = block.s
+            node.textContent = `${index}/ ${item}`
+          })
+          return container
         },
         (item, index) => index,
       )