fix vuejs#582

Author: 38elements

Diff for: packages/create-instance/create-instance.js

@@ -1,6 +1,7 @@
 // @flow
 
 import Vue from 'vue'
+import cloneDeep from 'lodash/cloneDeep'
 import { addSlots } from './add-slots'
 import { addScopedSlots } from './add-scoped-slots'
 import addMocks from './add-mocks'
@@ -92,6 +93,19 @@ export default function createInstance (
   addAttrs(vm, options.attrs)
   addListeners(vm, options.listeners)
 
+  vm.$_vueTestUtils_mountingOptionsSlots = options.slots
+  vm.$_vueTestUtils_originalSlots = cloneDeep(vm.$slots)
+  vm.$_vueTestUtils_originalUpdate = vm._update
+  vm._update = function (vnode, hydrating) {
+    // updating slot
+    if (this.$_vueTestUtils_mountingOptionsSlots) {
+      this.$slots = cloneDeep(this.$_vueTestUtils_originalSlots)
+      addSlots(this, this.$_vueTestUtils_mountingOptionsSlots)
+      vnode = this._render()
+    }
+    this.$_vueTestUtils_originalUpdate(vnode, hydrating)
+  }
+
   if (options.scopedSlots) {
     if (window.navigator.userAgent.match(/PhantomJS/i)) {
       throwError('the scopedSlots option does not support PhantomJS. Please use Puppeteer, or pass a component.')

Diff for: packages/test-utils/src/set-watchers-to-sync.js

@@ -27,10 +27,11 @@ export function setWatchersToSync (vm) {
 
   vm.$children.forEach(setWatchersToSync)
 
-  if (!vm.$_vueTestUtils_update) {
-    vm.$_vueTestUtils_update = vm._update
+  // preventing double registration
+  if (!vm.$_vueTestUtils_updateInSetWatcherSync) {
+    vm.$_vueTestUtils_updateInSetWatcherSync = vm._update
     vm._update = function (vnode, hydrating) {
-      this.$_vueTestUtils_update(vnode, hydrating)
+      this.$_vueTestUtils_updateInSetWatcherSync(vnode, hydrating)
       if (VUE_VERSION >= 2.1 && this._isMounted && this.$options.updated) {
         this.$options.updated.forEach((handler) => {
           handler.call(this)

Diff for: test/specs/mounting-options/slots.spec.js

@@ -113,6 +113,7 @@ describeWithMountingMethods('options.slots', (mountingMethod) => {
     const wrapper5 = mountingMethod(ComponentWithSlots, { slots: { default: '1{{ foo }}2' }})
     expect(wrapper5.find('main').html()).to.equal('<main>1bar2</main>')
     wrapper5.trigger('keydown')
+    expect(wrapper5.find('main').html()).to.equal('<main>1BAR2</main>')
     const wrapper6 = mountingMethod(ComponentWithSlots, { slots: { default: '<p>1</p><p>2</p>' }})
     expect(wrapper6.find('main').html()).to.equal('<main><p>1</p><p>2</p></main>')
     const wrapper7 = mountingMethod(ComponentWithSlots, { slots: { default: '1<p>2</p>3' }})