From 89158d7a7ceacb0a350848496230a4a0fab54c55 Mon Sep 17 00:00:00 2001
From: HcySunYang <HcySunYang@outlook.com>
Date: Wed, 26 Aug 2020 11:09:26 +0800
Subject: [PATCH 1/3] fix: class and style should be properly normalized in
 cloneVNode

---
 packages/runtime-core/src/vnode.ts | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/packages/runtime-core/src/vnode.ts b/packages/runtime-core/src/vnode.ts
index b444215ca26..0f20a534675 100644
--- a/packages/runtime-core/src/vnode.ts
+++ b/packages/runtime-core/src/vnode.ts
@@ -433,11 +433,7 @@ export function cloneVNode<T, U>(
   // This is intentionally NOT using spread or extend to avoid the runtime
   // key enumeration cost.
   const { props, patchFlag } = vnode
-  const mergedProps = extraProps
-    ? props
-      ? mergeProps(props, extraProps)
-      : extend({}, extraProps)
-    : props
+  const mergedProps = extraProps ? mergeProps(props || {}, extraProps) : props
   return {
     __v_isVNode: true,
     [ReactiveFlags.SKIP]: true,

From 6cb54fb47f7368d307882056406e87cff6f03324 Mon Sep 17 00:00:00 2001
From: HcySunYang <HcySunYang@outlook.com>
Date: Wed, 26 Aug 2020 13:40:44 +0800
Subject: [PATCH 2/3] test: add tests for cloneVNode

---
 packages/runtime-core/__tests__/vnode.spec.ts | 48 +++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/packages/runtime-core/__tests__/vnode.spec.ts b/packages/runtime-core/__tests__/vnode.spec.ts
index 2cab3215d40..b3e2c94fe0d 100644
--- a/packages/runtime-core/__tests__/vnode.spec.ts
+++ b/packages/runtime-core/__tests__/vnode.spec.ts
@@ -265,6 +265,54 @@ describe('vnode', () => {
     setCurrentRenderingInstance(null)
   })
 
+  test('cloneVNode class normalization', () => {
+    const vnode = createVNode('div', { class: 'a' })
+    const expectedProps = {
+      class: 'a b'
+    }
+    expect(cloneVNode(vnode, { class: 'b' }).props).toMatchObject(expectedProps)
+    expect(cloneVNode(vnode, { class: ['b'] }).props).toMatchObject(
+      expectedProps
+    )
+    expect(cloneVNode(vnode, { class: { b: true } }).props).toMatchObject(
+      expectedProps
+    )
+    expect(cloneVNode(vnode, { class: [{ b: true }] }).props).toMatchObject(
+      expectedProps
+    )
+  })
+
+  test('cloneVNode style normalization', () => {
+    const vnode = createVNode('div', { style: 'color: red;' })
+    const expectedProps = {
+      style: {
+        color: 'blue',
+        width: '300px'
+      }
+    }
+    expect(
+      cloneVNode(vnode, { style: 'color: blue; width: 300px;' }).props
+    ).toMatchObject(expectedProps)
+    expect(
+      cloneVNode(vnode, {
+        style: {
+          color: 'blue',
+          width: '300px'
+        }
+      }).props
+    ).toMatchObject(expectedProps)
+    expect(
+      cloneVNode(vnode, {
+        style: [
+          {
+            color: 'blue',
+            width: '300px'
+          }
+        ]
+      }).props
+    ).toMatchObject(expectedProps)
+  })
+
   describe('mergeProps', () => {
     test('class', () => {
       let props1: Data = { class: 'c' }

From 9b48f9305e1f3b411c00e54d8eb79b78cef4ca1b Mon Sep 17 00:00:00 2001
From: HcySunYang <HcySunYang@outlook.com>
Date: Wed, 26 Aug 2020 15:20:24 +0800
Subject: [PATCH 3/3] chore: tweak the tests

---
 packages/runtime-core/__tests__/vnode.spec.ts | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/packages/runtime-core/__tests__/vnode.spec.ts b/packages/runtime-core/__tests__/vnode.spec.ts
index b3e2c94fe0d..ad3575610a9 100644
--- a/packages/runtime-core/__tests__/vnode.spec.ts
+++ b/packages/runtime-core/__tests__/vnode.spec.ts
@@ -266,24 +266,26 @@ describe('vnode', () => {
   })
 
   test('cloneVNode class normalization', () => {
-    const vnode = createVNode('div', { class: 'a' })
+    const vnode = createVNode('div')
     const expectedProps = {
       class: 'a b'
     }
-    expect(cloneVNode(vnode, { class: 'b' }).props).toMatchObject(expectedProps)
-    expect(cloneVNode(vnode, { class: ['b'] }).props).toMatchObject(
-      expectedProps
-    )
-    expect(cloneVNode(vnode, { class: { b: true } }).props).toMatchObject(
+    expect(cloneVNode(vnode, { class: 'a b' }).props).toMatchObject(
       expectedProps
     )
-    expect(cloneVNode(vnode, { class: [{ b: true }] }).props).toMatchObject(
+    expect(cloneVNode(vnode, { class: ['a', 'b'] }).props).toMatchObject(
       expectedProps
     )
+    expect(
+      cloneVNode(vnode, { class: { a: true, b: true } }).props
+    ).toMatchObject(expectedProps)
+    expect(
+      cloneVNode(vnode, { class: [{ a: true, b: true }] }).props
+    ).toMatchObject(expectedProps)
   })
 
   test('cloneVNode style normalization', () => {
-    const vnode = createVNode('div', { style: 'color: red;' })
+    const vnode = createVNode('div')
     const expectedProps = {
       style: {
         color: 'blue',