From 33d0e907cbec5deaca6b47e6ee4688f02678e8bc Mon Sep 17 00:00:00 2001
From: BeiYuShuiGuoLvDeKongQi <958414905@qq.com>
Date: Wed, 12 Aug 2020 00:51:24 +0800
Subject: [PATCH 1/4] fix(runtime-core/Teleport): handle 0 as patchFlag
 value.(#1813)

---
 packages/runtime-core/src/components/Teleport.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/runtime-core/src/components/Teleport.ts b/packages/runtime-core/src/components/Teleport.ts
index 8c588df128b..30754aa255b 100644
--- a/packages/runtime-core/src/components/Teleport.ts
+++ b/packages/runtime-core/src/components/Teleport.ts
@@ -139,7 +139,7 @@ export const TeleportImpl = {
           parentSuspense,
           isSVG
         )
-        if (n2.patchFlag > 0 && n2.shapeFlag & ShapeFlags.ARRAY_CHILDREN) {
+        if (n2.patchFlag >= 0 && n2.shapeFlag & ShapeFlags.ARRAY_CHILDREN) {
           const oldChildren = n1.children as VNode[]
           const children = n2.children as VNode[]
           for (let i = 0; i < children.length; i++) {

From d63e561fcd92a9b22f56445be08c31817bb637d9 Mon Sep 17 00:00:00 2001
From: BeiYuShuiGuoLvDeKongQi <958414905@qq.com>
Date: Wed, 12 Aug 2020 21:30:08 +0800
Subject: [PATCH 2/4] chore(runtime-core/Teleport): add test

---
 packages/vue/__tests__/index.spec.ts | 39 ++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/packages/vue/__tests__/index.spec.ts b/packages/vue/__tests__/index.spec.ts
index 974fffc0442..7339a0804fa 100644
--- a/packages/vue/__tests__/index.spec.ts
+++ b/packages/vue/__tests__/index.spec.ts
@@ -208,4 +208,43 @@ describe('compiler + runtime integration', () => {
     ).toHaveBeenWarned()
     document.querySelector = origin
   })
+
+  // #1813
+  it('should not report an error when "0" as patchFlag value', async () => {
+    const container = document.createElement('div')
+    const target = document.createElement('div')
+    const count = ref(0)
+    const origin = document.querySelector
+    document.querySelector = jest.fn().mockReturnValue(target)
+
+    const App = {
+      template: `
+      <teleport v-if="count < 2" to="#target">
+        <div>
+          <div>{{ count }}</div>
+        </div>
+      </teleport>
+      `,
+      data() {
+        return {
+          count
+        }
+      }
+    }
+    createApp(App).mount(container)
+    expect(container.innerHTML).toBe(`<!--teleport start--><!--teleport end-->`)
+    expect(target.innerHTML).toBe(`<div><div>0</div></div>`)
+
+    count.value++
+    await nextTick()
+    expect(container.innerHTML).toBe(`<!--teleport start--><!--teleport end-->`)
+    expect(target.innerHTML).toBe(`<div><div>1</div></div>`)
+
+    count.value++
+    await nextTick()
+    expect(container.innerHTML).toBe(`<!--v-if-->`)
+    expect(target.innerHTML).toBe(``)
+
+    document.querySelector = origin
+  })
 })

From 9126499d47038c4c6523279b331f3f6908fe2664 Mon Sep 17 00:00:00 2001
From: BeiYuShuiGuoLvDeKongQi <958414905@qq.com>
Date: Wed, 12 Aug 2020 21:51:17 +0800
Subject: [PATCH 3/4] chore(runtime-core/Teleport): add comment

---
 packages/runtime-core/src/components/Teleport.ts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/packages/runtime-core/src/components/Teleport.ts b/packages/runtime-core/src/components/Teleport.ts
index 30754aa255b..24f6e1417c7 100644
--- a/packages/runtime-core/src/components/Teleport.ts
+++ b/packages/runtime-core/src/components/Teleport.ts
@@ -139,6 +139,8 @@ export const TeleportImpl = {
           parentSuspense,
           isSVG
         )
+        // #1813, sometimes when the patchFlag is 0,
+        // this branch may need to run
         if (n2.patchFlag >= 0 && n2.shapeFlag & ShapeFlags.ARRAY_CHILDREN) {
           const oldChildren = n1.children as VNode[]
           const children = n2.children as VNode[]

From d76acf59f430fe24c4055ff1a12cb5fcce1251d9 Mon Sep 17 00:00:00 2001
From: Evan You <yyx990803@gmail.com>
Date: Fri, 14 Aug 2020 17:18:39 -0400
Subject: [PATCH 4/4] Update Teleport.ts

---
 packages/runtime-core/src/components/Teleport.ts | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/packages/runtime-core/src/components/Teleport.ts b/packages/runtime-core/src/components/Teleport.ts
index 24f6e1417c7..ca885c3d920 100644
--- a/packages/runtime-core/src/components/Teleport.ts
+++ b/packages/runtime-core/src/components/Teleport.ts
@@ -139,9 +139,10 @@ export const TeleportImpl = {
           parentSuspense,
           isSVG
         )
-        // #1813, sometimes when the patchFlag is 0,
-        // this branch may need to run
-        if (n2.patchFlag >= 0 && n2.shapeFlag & ShapeFlags.ARRAY_CHILDREN) {
+        // even in block tree mode we need to make sure all root-level nodes
+        // in the teleport inherit previous DOM references so that they can
+        // be moved in future patches.
+        if (n2.shapeFlag & ShapeFlags.ARRAY_CHILDREN) {
           const oldChildren = n1.children as VNode[]
           const children = n2.children as VNode[]
           for (let i = 0; i < children.length; i++) {