From aead1660ea7f54b45c4f0193270d4fa3bc62b930 Mon Sep 17 00:00:00 2001
From: ygj6 <yuangongji@foxmail.com>
Date: Tue, 11 May 2021 15:29:26 +0800
Subject: [PATCH 1/3] fix: The behavior of dev and production merge should be
 consistent.

---
 src/utils/instance.ts | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/utils/instance.ts b/src/utils/instance.ts
index 3ee24edc..95168791 100644
--- a/src/utils/instance.ts
+++ b/src/utils/instance.ts
@@ -36,7 +36,12 @@ export function asVmProperty(
             },
           })
         } else {
-          vm._data[propName] = propValue
+          proxy(vm._data, propName, {
+            get: () => propValue,
+            set: (val: any) => {
+              propValue = val
+            },
+          })
         }
       })
     }

From 055d14d8966e90f771f36c9dbe0606180a972de1 Mon Sep 17 00:00:00 2001
From: ygj6 <yuangongji@foxmail.com>
Date: Tue, 11 May 2021 16:38:57 +0800
Subject: [PATCH 2/3] test: add test cases.

---
 test/setup.spec.js | 88 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)

diff --git a/test/setup.spec.js b/test/setup.spec.js
index 35329849..db4fc0ae 100644
--- a/test/setup.spec.js
+++ b/test/setup.spec.js
@@ -896,6 +896,94 @@ describe('setup', () => {
     expect(vm.$el.textContent).toBe('2')
   })
 
+  //#679
+  it('should work merge with object in development', async () => {
+    global.__DEV__ = true
+    const vm = new Vue({
+      template: '<div>{{ data.id }}</div>',
+      setup() {
+        const data = reactive({
+          id: 42,
+        });
+        return { data }
+      },
+      data() {
+        return {
+          data: { id: 1 },
+        }
+      },
+    }).$mount()
+
+    await nextTick()
+    expect(vm.$el.textContent).toBe('1')
+  })
+
+  //#679
+  it('should work merge with object in production', async () => {
+    global.__DEV__ = false
+    const vm = new Vue({
+      template: '<div>{{ data.id }}</div>',
+      setup() {
+        const data = reactive({
+          id: 42,
+        });
+        return { data }
+      },
+      data() {
+        return {
+          data: { id: 1 },
+        }
+      },
+    }).$mount()
+
+    await nextTick()
+    expect(vm.$el.textContent).toBe('1')
+  })
+
+  //#679
+  it('should work merge with data in development', async () => {
+    global.__DEV__ = true
+    const vm = new Vue({
+      template: '<div>{{ id }}</div>',
+      setup() {
+        const data = reactive({
+          id: 42,
+        });
+        return data
+      },
+      data() {
+        return {
+          id: 1,
+        }
+      },
+    }).$mount()
+
+    await nextTick()
+    expect(vm.$el.textContent).toBe('1')
+  })
+
+  //#679
+  it('should work merge with data in production', async () => {
+    global.__DEV__ = false
+    const vm = new Vue({
+      template: '<div>{{ id }}</div>',
+      setup() {
+        const data = reactive({
+          id: 42,
+        });
+        return data
+      },
+      data() {
+        return {
+          id: 1,
+        }
+      },
+    }).$mount()
+
+    await nextTick()
+    expect(vm.$el.textContent).toBe('1')
+  })
+
   // #524
   it('should work with reactive arrays.', async () => {
     const opts = {

From 0400f9193518f6ef69b1590a46b9f9ced0bfdb7d Mon Sep 17 00:00:00 2001
From: Anthony Fu <anthonyfu117@hotmail.com>
Date: Wed, 19 May 2021 17:33:22 +0800
Subject: [PATCH 3/3] chore: fix conflict

---
 test/setup.spec.js | 50 ++++------------------------------------------
 1 file changed, 4 insertions(+), 46 deletions(-)

diff --git a/test/setup.spec.js b/test/setup.spec.js
index 0e9a65e1..e1ac9a6d 100644
--- a/test/setup.spec.js
+++ b/test/setup.spec.js
@@ -898,7 +898,7 @@ describe('setup', () => {
     expect(vm.$el.textContent).toBe('2')
   })
 
-  //#679
+  // #679
   it('should work merge with object in development', async () => {
     global.__DEV__ = true
     const vm = new Vue({
@@ -906,7 +906,7 @@ describe('setup', () => {
       setup() {
         const data = reactive({
           id: 42,
-        });
+        })
         return { data }
       },
       data() {
@@ -920,7 +920,7 @@ describe('setup', () => {
     expect(vm.$el.textContent).toBe('1')
   })
 
-  //#679
+  // #679
   it('should work merge with object in production', async () => {
     global.__DEV__ = false
     const vm = new Vue({
@@ -928,7 +928,7 @@ describe('setup', () => {
       setup() {
         const data = reactive({
           id: 42,
-        });
+        })
         return { data }
       },
       data() {
@@ -942,48 +942,6 @@ describe('setup', () => {
     expect(vm.$el.textContent).toBe('1')
   })
 
-  //#679
-  it('should work merge with data in development', async () => {
-    global.__DEV__ = true
-    const vm = new Vue({
-      template: '<div>{{ id }}</div>',
-      setup() {
-        const data = reactive({
-          id: 42,
-        });
-        return data
-      },
-      data() {
-        return {
-          id: 1,
-        }
-      },
-    }).$mount()
-
-    await nextTick()
-    expect(vm.$el.textContent).toBe('1')
-  })
-
-  //#679
-  it('should work merge with data in production', async () => {
-    global.__DEV__ = false
-    const vm = new Vue({
-      template: '<div>{{ id }}</div>',
-      setup() {
-        const data = reactive({
-          id: 42,
-        });
-        return data
-      },
-      data() {
-        return {
-          id: 1,
-        }
-      },
-    }).$mount()
-
-    await nextTick()
-    expect(vm.$el.textContent).toBe('1')
   // #683 #603 #580
   it('should update directly when adding attributes to a reactive object', async () => {
     const vm = new Vue({