From c3831c35e08d155a845e6f5e4fe28a14f81fe50f Mon Sep 17 00:00:00 2001
From: gebilaoxiong <gebilaoxiong@gmail.com>
Date: Fri, 28 Apr 2017 11:58:38 +0800
Subject: [PATCH 1/3] fix:create empty vnode when functional component return
 null

---
 src/core/vdom/create-element.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/core/vdom/create-element.js b/src/core/vdom/create-element.js
index b9c1d0889ac..9f0f23e64c0 100644
--- a/src/core/vdom/create-element.js
+++ b/src/core/vdom/create-element.js
@@ -99,7 +99,7 @@ export function _createElement (
     // direct component options / constructor
     vnode = createComponent(tag, data, context, children)
   }
-  if (vnode !== undefined) {
+  if (vnode != null) {
     if (ns) applyNS(vnode, ns)
     return vnode
   } else {

From af0629c943df4505f8a8870518d1510662d33162 Mon Sep 17 00:00:00 2001
From: gebilaoxiong <gebilaoxiong@gmail.com>
Date: Fri, 28 Apr 2017 13:24:20 +0800
Subject: [PATCH 2/3] add test

---
 test/unit/features/options/functional.spec.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/unit/features/options/functional.spec.js b/test/unit/features/options/functional.spec.js
index 9345b60e045..9bdff840aca 100644
--- a/test/unit/features/options/functional.spec.js
+++ b/test/unit/features/options/functional.spec.js
@@ -1,4 +1,5 @@
 import Vue from 'vue'
+import { createEmptyVNode } from 'core/vdom/vnode'
 
 describe('Options functional', () => {
   it('should work', done => {
@@ -167,4 +168,21 @@ describe('Options functional', () => {
       vm.$destroy()
     }).then(done)
   })
+
+  it('create empty vnode when render return null', () => {
+    const child = {
+      functional: true,
+      render () {
+        return null
+      }
+    }
+    const vm = new Vue({
+      components: {
+        child
+      }
+    })
+    const h = vm.$createElement
+    const vnode = h('child')
+    expect(vnode).toEqual(createEmptyVNode())
+  })
 })

From ed691b09da9e3005871add9a849bcd1ed8ba66e2 Mon Sep 17 00:00:00 2001
From: Evan You <yyx990803@gmail.com>
Date: Sat, 29 Apr 2017 14:40:46 +0800
Subject: [PATCH 3/3] use isDef

---
 src/core/vdom/create-element.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/core/vdom/create-element.js b/src/core/vdom/create-element.js
index 9f0f23e64c0..daa29b80ada 100644
--- a/src/core/vdom/create-element.js
+++ b/src/core/vdom/create-element.js
@@ -99,7 +99,7 @@ export function _createElement (
     // direct component options / constructor
     vnode = createComponent(tag, data, context, children)
   }
-  if (vnode != null) {
+  if (isDef(vnode)) {
     if (ns) applyNS(vnode, ns)
     return vnode
   } else {