From 4e0cae288fbebc1f7e1f1c6db2b221abdafecc31 Mon Sep 17 00:00:00 2001
From: zhufengzhufeng <894918097@qq.com>
Date: Thu, 25 Feb 2021 19:56:27 +0800
Subject: [PATCH] perf(reactivity):Don't add the existing attributes of set

---
 packages/reactivity/src/collectionHandlers.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/reactivity/src/collectionHandlers.ts b/packages/reactivity/src/collectionHandlers.ts
index e43d3ac59fd..149bcb54d2c 100644
--- a/packages/reactivity/src/collectionHandlers.ts
+++ b/packages/reactivity/src/collectionHandlers.ts
@@ -76,8 +76,8 @@ function add(this: SetTypes, value: unknown) {
   const target = toRaw(this)
   const proto = getProto(target)
   const hadKey = proto.has.call(target, value)
-  target.add(value)
   if (!hadKey) {
+    target.add(value)
     trigger(target, TriggerOpTypes.ADD, value, value)
   }
   return this