From 0664cb01434f3d52efd076b6aafe54066a2a762a Mon Sep 17 00:00:00 2001
From: Alex Addams <xmakina@users.noreply.github.com>
Date: Mon, 21 Sep 2020 16:42:08 +0100
Subject: [PATCH] fix(v-pre): do not alter attributes (#10088)

* fix(v-pre): do not alter attributes

close #10087

* fix(v-pre): do not alter attributes

remove component and replace option from unit test

* refactor: use or

* perf: check boolean before index

Co-authored-by: Eduardo San Martin Morote <posva@users.noreply.github.com>
---
 src/platforms/web/runtime/modules/attrs.js | 6 +++---
 test/unit/features/directives/pre.spec.js  | 9 +++++++++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/platforms/web/runtime/modules/attrs.js b/src/platforms/web/runtime/modules/attrs.js
index b5e06403..f6dc500a 100644
--- a/src/platforms/web/runtime/modules/attrs.js
+++ b/src/platforms/web/runtime/modules/attrs.js
@@ -39,7 +39,7 @@ function updateAttrs (oldVnode: VNodeWithData, vnode: VNodeWithData) {
     cur = attrs[key]
     old = oldAttrs[key]
     if (old !== cur) {
-      setAttr(elm, key, cur)
+      setAttr(elm, key, cur, vnode.data.pre)
     }
   }
   // #4391: in IE9, setting type can reset value for input[type=radio]
@@ -59,8 +59,8 @@ function updateAttrs (oldVnode: VNodeWithData, vnode: VNodeWithData) {
   }
 }
 
-function setAttr (el: Element, key: string, value: any) {
-  if (el.tagName.indexOf('-') > -1) {
+function setAttr (el: Element, key: string, value: any, isInPre: any) {
+  if (isInPre || el.tagName.indexOf('-') > -1) {
     baseSetAttr(el, key, value)
   } else if (isBooleanAttr(key)) {
     // set attribute for blank value
diff --git a/test/unit/features/directives/pre.spec.js b/test/unit/features/directives/pre.spec.js
index ed48bf0f..65def9cd 100644
--- a/test/unit/features/directives/pre.spec.js
+++ b/test/unit/features/directives/pre.spec.js
@@ -42,4 +42,13 @@ describe('Directive v-pre', function () {
     vm.$mount()
     expect(vm.$el.firstChild.tagName).toBe('VTEST')
   })
+
+  // #10087
+  it('should not compile attributes', function () {
+    const vm = new Vue({
+      template: '<div v-pre><p open="hello">A Test</p></div>'
+    })
+    vm.$mount()
+    expect(vm.$el.firstChild.getAttribute('open')).toBe('hello')
+  })
 })