From 7cbf68461118ced0c7c6eb79a395ae2b148e3737 Mon Sep 17 00:00:00 2001
From: Evan You <yyx990803@gmail.com>
Date: Mon, 13 Apr 2020 12:37:31 -0400
Subject: [PATCH] fix(runtime-core): fix kebab-case props update

fix #955
---
 .../__tests__/componentProps.spec.ts          | 23 ++++++++++++-------
 packages/runtime-core/src/componentProps.ts   |  9 +++++++-
 2 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/packages/runtime-core/__tests__/componentProps.spec.ts b/packages/runtime-core/__tests__/componentProps.spec.ts
index 4ee39db8..402fc0d6 100644
--- a/packages/runtime-core/__tests__/componentProps.spec.ts
+++ b/packages/runtime-core/__tests__/componentProps.spec.ts
@@ -20,7 +20,7 @@ describe('component props', () => {
     let proxy: any
 
     const Comp = defineComponent({
-      props: ['foo'],
+      props: ['fooBar'],
       render() {
         props = this.$props
         attrs = this.$attrs
@@ -29,18 +29,25 @@ describe('component props', () => {
     })
 
     const root = nodeOps.createElement('div')
-    render(h(Comp, { foo: 1, bar: 2 }), root)
-    expect(proxy.foo).toBe(1)
-    expect(props).toEqual({ foo: 1 })
+    render(h(Comp, { fooBar: 1, bar: 2 }), root)
+    expect(proxy.fooBar).toBe(1)
+    expect(props).toEqual({ fooBar: 1 })
     expect(attrs).toEqual({ bar: 2 })
 
-    render(h(Comp, { foo: 2, bar: 3, baz: 4 }), root)
-    expect(proxy.foo).toBe(2)
-    expect(props).toEqual({ foo: 2 })
+    // test passing kebab-case and resolving to camelCase
+    render(h(Comp, { 'foo-bar': 2, bar: 3, baz: 4 }), root)
+    expect(proxy.fooBar).toBe(2)
+    expect(props).toEqual({ fooBar: 2 })
+    expect(attrs).toEqual({ bar: 3, baz: 4 })
+
+    // test updating kebab-case should not delete it (#955)
+    render(h(Comp, { 'foo-bar': 3, bar: 3, baz: 4 }), root)
+    expect(proxy.fooBar).toBe(3)
+    expect(props).toEqual({ fooBar: 3 })
     expect(attrs).toEqual({ bar: 3, baz: 4 })
 
     render(h(Comp, { qux: 5 }), root)
-    expect(proxy.foo).toBeUndefined()
+    expect(proxy.fooBar).toBeUndefined()
     expect(props).toEqual({})
     expect(attrs).toEqual({ qux: 5 })
   })
diff --git a/packages/runtime-core/src/componentProps.ts b/packages/runtime-core/src/componentProps.ts
index 2ceb9aa9..0ca0dbaa 100644
--- a/packages/runtime-core/src/componentProps.ts
+++ b/packages/runtime-core/src/componentProps.ts
@@ -177,8 +177,15 @@ export function updateProps(
     setFullProps(instance, rawProps, props, attrs)
     // in case of dynamic props, check if we need to delete keys from
     // the props object
+    let kebabKey: string
     for (const key in rawCurrentProps) {
-      if (!rawProps || !hasOwn(rawProps, key)) {
+      if (
+        !rawProps ||
+        (!hasOwn(rawProps, key) &&
+          // it's possible the original props was passed in as kebab-case
+          // and converted to camelCase (#955)
+          ((kebabKey = hyphenate(key)) === key || !hasOwn(rawProps, kebabKey)))
+      ) {
         delete props[key]
       }
     }