only use click for v-model checkbox/radio in Chrome (fix #4796, #4896)

src/core/util/env.js

@@ -14,6 +14,7 @@ export const isIE9 = UA && UA.indexOf('msie 9.0') > 0
 export const isEdge = UA && UA.indexOf('edge/') > 0
 export const isAndroid = UA && UA.indexOf('android') > 0
 export const isIOS = UA && /iphone|ipad|ipod|ios/.test(UA)
+export const isChrome = UA && /chrome\/\d+/.test(UA) && !isEdge
 
 // this needs to be lazy-evaled because vue may be required before
 // vue-server-renderer can set VUE_ENV

src/entries/web-runtime.js

@@ -5,7 +5,7 @@ import config from 'core/config'
 import { patch } from 'web/runtime/patch'
 import { extend, noop } from 'shared/util'
 import { mountComponent } from 'core/instance/lifecycle'
-import { devtools, inBrowser, isEdge } from 'core/util/index'
+import { devtools, inBrowser, isChrome } from 'core/util/index'
 import platformDirectives from 'web/runtime/directives/index'
 import platformComponents from 'web/runtime/components/index'
 
@@ -45,10 +45,7 @@ setTimeout(() => {
   if (config.devtools) {
     if (devtools) {
       devtools.emit('init', Vue)
-    } else if (
-      process.env.NODE_ENV !== 'production' &&
-      inBrowser && !isEdge && /Chrome\/\d+/.test(window.navigator.userAgent)
-    ) {
+    } else if (process.env.NODE_ENV !== 'production' && isChrome) {
       console[console.info ? 'info' : 'log'](
         'Download the Vue Devtools extension for a better development experience:\n' +
         'https://github.com/vuejs/vue-devtools'

src/platforms/web/compiler/directives/model.js

@@ -1,12 +1,16 @@
 /* @flow */
 
 import config from 'core/config'
-import { isIE } from 'core/util/env'
 import { addHandler, addProp, getBindingAttr } from 'compiler/helpers'
 import { genComponentModel, genAssignmentCode } from 'compiler/directives/model'
 
 let warn
 
+// in some cases, the event used has to be determined at runtime
+// so we used some reserved tokens during compile.
+export const RANGE_TOKEN = '__r'
+export const CHECKBOX_RADIO_TOKEN = '__c'
+
 export default function model (
   el: ASTElement,
   dir: ASTDirective,
@@ -86,7 +90,7 @@ function genCheckboxModel (
           : `:_q(${value},${trueValueBinding})`
       )
   )
-  addHandler(el, 'click',
+  addHandler(el, CHECKBOX_RADIO_TOKEN,
     `var $$a=${value},` +
         '$$el=$event.target,' +
         `$$c=$$el.checked?(${trueValueBinding}):(${falseValueBinding});` +
@@ -117,7 +121,7 @@ function genRadioModel (
   let valueBinding = getBindingAttr(el, 'value') || 'null'
   valueBinding = number ? `_n(${valueBinding})` : valueBinding
   addProp(el, 'checked', `_q(${value},${valueBinding})`)
-  addHandler(el, 'click', genAssignmentCode(value, valueBinding), null, true)
+  addHandler(el, CHECKBOX_RADIO_TOKEN, genAssignmentCode(value, valueBinding), null, true)
 }
 
 function genSelect (
@@ -162,8 +166,12 @@ function genDefaultModel (
 ): ?boolean {
   const type = el.attrsMap.type
   const { lazy, number, trim } = modifiers || {}
-  const event = lazy || (isIE && type === 'range') ? 'change' : 'input'
   const needCompositionGuard = !lazy && type !== 'range'
+  const event = lazy
+    ? 'change'
+    : type === 'range'
+      ? RANGE_TOKEN
+      : 'input'
 
   let valueExpression = '$event.target.value'
   if (trim) {

src/platforms/web/runtime/modules/events.js

@@ -1,6 +1,28 @@
 /* @flow */
 
+import { isChrome, isIE } from 'core/util/env'
 import { updateListeners } from 'core/vdom/helpers/index'
+import { RANGE_TOKEN, CHECKBOX_RADIO_TOKEN } from 'web/compiler/directives/model'
+
+// normalize v-model event tokens that can only be determined at runtime.
+// it's important to place the event as the first in the array because
+// the whole point is ensuring the v-model callback gets called before
+// user-attached handlers.
+function normalizeEvents (on) {
+  let event
+  if (on[RANGE_TOKEN]) {
+    // IE input[type=range] only supports `change` event
+    event = isIE ? 'change' : 'input'
+    on[event] = [].concat(on[RANGE_TOKEN], on[event] || [])
+    delete on[RANGE_TOKEN]
+  }
+  if (on[CHECKBOX_RADIO_TOKEN]) {
+    // Chrome fires microtasks in between click/change, leads to #4521
+    event = isChrome ? 'click' : 'change'
+    on[event] = [].concat(on[CHECKBOX_RADIO_TOKEN], on[event] || [])
+    delete on[CHECKBOX_RADIO_TOKEN]
+  }
+}
 
 let target: HTMLElement
 
@@ -41,6 +63,7 @@ function updateDOMListeners (oldVnode: VNodeWithData, vnode: VNodeWithData) {
   const on = vnode.data.on || {}
   const oldOn = oldVnode.data.on || {}
   target = vnode.elm
+  normalizeEvents(on)
   updateListeners(on, oldOn, add, remove, vnode.context)
 }