From 1d55454e61bf18cc2d6fe948c4528a680f67efe5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E1=B4=9C=C9=B4=D0=B2=CA=8F=D1=82=E1=B4=87?=
 <i@shangyes.net>
Date: Tue, 25 Aug 2020 21:47:55 +0800
Subject: [PATCH] fix(runtime-dom): avoid setting unchanged input value (#1937)

fix #1935 (fix v-model usage with HTML5 validation)
---
 packages/runtime-dom/src/directives/vModel.ts | 5 ++++-
 packages/runtime-dom/src/modules/props.ts     | 5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/packages/runtime-dom/src/directives/vModel.ts b/packages/runtime-dom/src/directives/vModel.ts
index 0516569f1..23ebb07b3 100644
--- a/packages/runtime-dom/src/directives/vModel.ts
+++ b/packages/runtime-dom/src/directives/vModel.ts
@@ -85,7 +85,10 @@ export const vModelText: ModelDirective<
         return
       }
     }
-    el.value = value == null ? '' : value
+    const newValue = value == null ? '' : value
+    if (el.value !== newValue) {
+      el.value = newValue
+    }
   }
 }
 
diff --git a/packages/runtime-dom/src/modules/props.ts b/packages/runtime-dom/src/modules/props.ts
index ebecc8972..1a50d612b 100644
--- a/packages/runtime-dom/src/modules/props.ts
+++ b/packages/runtime-dom/src/modules/props.ts
@@ -28,7 +28,10 @@ export function patchDOMProp(
     // store value as _value as well since
     // non-string values will be stringified.
     el._value = value
-    el.value = value == null ? '' : value
+    const newValue = value == null ? '' : value
+    if (el.value !== newValue) {
+      el.value = newValue
+    }
     return
   }
   if (value === '' && typeof el[key] === 'boolean') {