From 62d2fe02acff8003660639cec1cadd6b7b6fbf7e Mon Sep 17 00:00:00 2001
From: ygj6 <yuangongji@foxmail.com>
Date: Fri, 9 Jul 2021 14:54:18 +0800
Subject: [PATCH 1/2] fix(customReactive): avoid circular reference.

---
 src/mixin.ts | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/mixin.ts b/src/mixin.ts
index 3adde308..a235648b 100644
--- a/src/mixin.ts
+++ b/src/mixin.ts
@@ -149,7 +149,8 @@ export function mixin(Vue: VueConstructor) {
     }
   }
 
-  function customReactive(target: object) {
+  function customReactive(target: object, visited = new Set()) {
+    if (visited.has(target)) return
     if (
       !isPlainObject(target) ||
       isRef(target) ||
@@ -165,7 +166,8 @@ export function mixin(Vue: VueConstructor) {
       const val = target[k]
       defineReactive(target, k, val)
       if (val) {
-        customReactive(val)
+        visited.add(val)
+        customReactive(val, visited)
       }
       return
     })

From 91d88975c78c5376972365ac586d37c5a8e750c1 Mon Sep 17 00:00:00 2001
From: ygj6 <yuangongji@foxmail.com>
Date: Mon, 12 Jul 2021 14:53:57 +0800
Subject: [PATCH 2/2] test: add test case

---
 test/setupContext.spec.ts | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/test/setupContext.spec.ts b/test/setupContext.spec.ts
index cb602031..6ec978f7 100644
--- a/test/setupContext.spec.ts
+++ b/test/setupContext.spec.ts
@@ -5,9 +5,12 @@ import {
   ref,
   nextTick,
   SetupContext,
+  getCurrentInstance,
 } from '../src'
+import { mockWarn } from './helpers'
 
 describe('setupContext', () => {
+  mockWarn(true)
   it('should have proper properties', () => {
     let context: SetupContext = undefined!
 
@@ -195,4 +198,31 @@ describe('setupContext', () => {
 
     expect(_attrs.foo).toBe('bar2')
   })
+
+  // #563
+  it('should not RangeError: Maximum call stack size exceeded', async () => {
+    createApp(
+      defineComponent({
+        template: `<div/>`,
+        setup() {
+          // @ts-expect-error
+          const app = getCurrentInstance().proxy
+          let mockNT: any = []
+          mockNT.__ob__ = {}
+          const test = {
+            app,
+            mockNT,
+          }
+          return {
+            test,
+          }
+        },
+      })
+    ).mount()
+
+    await nextTick()
+    expect(
+      `"RangeError: Maximum call stack size exceeded"`
+    ).not.toHaveBeenWarned()
+  })
 })