refactor: remove sync mode (#1141)

BREAKING CHANGE:

* Remove `sync` mode
* Remove TransitionStub
* Remove Transition

Author: eddyerburgh

Diff for: package.json

@@ -36,7 +36,7 @@
     "babel-plugin-syntax-jsx": "^6.18.0",
     "babel-plugin-transform-decorators-legacy": "^1.3.4",
     "babel-plugin-transform-vue-jsx": "^3.7.0",
-    "babel-polyfill": "^6.23.0",
+    "babel-polyfill": "^6.26.0",
     "babel-preset-env": "^1.6.0",
     "babel-preset-flow-vue": "^1.0.0",
     "babel-preset-stage-2": "^6.24.1",

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

@@ -11,7 +11,6 @@ const MOUNTING_OPTIONS = [
   'attrs',
   'listeners',
   'propsData',
-  'sync',
   'shouldProxy'
 ]
 

Diff for: packages/server-test-utils/types/index.d.ts

@@ -36,7 +36,6 @@ interface MountOptions<V extends Vue> extends ComponentOptions<V> {
   stubs?: Stubs,
   attrs?: Record<string, string>
   listeners?: Record<string, Function | Function[]>
-  sync?: boolean
 }
 
 type ThisTypedMountOptions<V extends Vue> = MountOptions<V> & ThisType<V>

Diff for: packages/server-test-utils/types/test/renderToString.ts

@@ -12,8 +12,7 @@ render(
     attachToDocument: true,
     scopedSlots: {
       foo: `<div>Foo</div>`
-    },
-    sync: false
+    }
   }
 )
 

Diff for: packages/shared/consts.js

@@ -6,7 +6,6 @@ export const COMPONENT_SELECTOR = 'COMPONENT_SELECTOR'
 export const REF_SELECTOR = 'REF_SELECTOR'
 export const DOM_SELECTOR = 'DOM_SELECTOR'
 export const INVALID_SELECTOR = 'INVALID_SELECTOR'
-export const COMPAT_SYNC_MODE = 'COMPAT_SYNC_MODE'
 
 export const VUE_VERSION = Number(
   `${Vue.version.split('.')[0]}.${Vue.version.split('.')[1]}`

Diff for: packages/shared/merge-options.js

@@ -41,7 +41,6 @@ export function mergeOptions(
     provide: normalizeProvide(provide),
     stubs,
     mocks,
-    methods,
-    sync: !!(options.sync || options.sync === undefined)
+    methods
   }
 }

Diff for: packages/test-utils/src/components/TransitionGroupStub.js

@@ -249,13 +249,6 @@ export default class ErrorWrapper implements BaseWrapper {
     )
   }
 
-  update(): void {
-    throwError(
-      `update has been removed from vue-test-utils.` +
-        `All updates are now synchronous by default`
-    )
-  }
-
   destroy(): void {
     throwError(
       `find did not return ${

Diff for: packages/test-utils/src/components/TransitionStub.js

@@ -1,8 +1,6 @@
 import shallowMount from './shallow-mount'
 import mount from './mount'
 import createLocalVue from './create-local-vue'
-import TransitionStub from './components/TransitionStub'
-import TransitionGroupStub from './components/TransitionGroupStub'
 import RouterLinkStub from './components/RouterLinkStub'
 import createWrapper from './create-wrapper'
 import Wrapper from './wrapper'
@@ -25,8 +23,6 @@ export default {
   mount,
   shallow,
   shallowMount,
-  TransitionStub,
-  TransitionGroupStub,
   RouterLinkStub,
   Wrapper,
   WrapperArray

Diff for: packages/test-utils/src/error-wrapper.js

@@ -7,63 +7,11 @@ import config from './config'
 import warnIfNoWindow from './warn-if-no-window'
 import createWrapper from './create-wrapper'
 import createLocalVue from './create-local-vue'
-import { warn } from 'shared/util'
-import semver from 'semver'
-import { COMPAT_SYNC_MODE } from 'shared/consts'
 import { validateOptions } from 'shared/validate-options'
-import TransitionGroupStub from './components/TransitionGroupStub'
-import TransitionStub from './components/TransitionStub'
 
 Vue.config.productionTip = false
 Vue.config.devtools = false
 
-function getSyncOption(syncOption) {
-  if (syncOption === false) {
-    Vue.config.async = true
-    return false
-  }
-  if (semver.lt(Vue.version, '2.5.18')) {
-    warn(
-      `Vue Test Utils runs in sync mode by default. Due to bugs, sync mode ` +
-        `requires Vue > 2.5.18. In Vue Test Utils 1.0 sync mode will only be ` +
-        `supported with Vue 2.5.18+ running in development mode. If you are ` +
-        `unable to upgrade, you should rewrite your tests to run asynchronously` +
-        `you can do this by setting the sync mounting option to false.`
-    )
-    return COMPAT_SYNC_MODE
-  }
-
-  if (typeof Vue.config.async === 'undefined') {
-    warn(
-      `Sync mode only works when Vue runs in dev mode. ` +
-        `Please set Vue to run in dev mode, or set sync to false`
-    )
-  }
-
-  Vue.config.async = false
-  return true
-}
-
-function addTransitionStubs(options) {
-  if (config.stubs === false) {
-    return
-  }
-  if (
-    options.stubs &&
-    options.stubs.transition !== false &&
-    !options.stubs.transition
-  ) {
-    options.stubs.transition = TransitionStub
-  }
-  if (
-    options.stubs &&
-    options.stubs['transition-group'] !== false &&
-    !options.stubs['transition-group']
-  ) {
-    options.stubs['transition-group'] = TransitionGroupStub
-  }
-}
-
 export default function mount(component, options = {}) {
   warnIfNoWindow()
 
@@ -72,17 +20,9 @@ export default function mount(component, options = {}) {
   const _Vue = createLocalVue(options.localVue)
 
   const mergedOptions = mergeOptions(options, config)
-  const sync = getSyncOption(mergedOptions.sync)
 
   validateOptions(mergedOptions, component)
 
-  // Stub transition and transition-group if in compat sync mode to keep old
-  // behavior
-  // TODO: Remove when compat sync mode is removed
-  if (sync === COMPAT_SYNC_MODE) {
-    addTransitionStubs(mergedOptions)
-  }
-
   const parentVm = createInstance(component, mergedOptions, _Vue)
 
   const el = options.attachToDocument ? createElement() : undefined
@@ -93,8 +33,7 @@ export default function mount(component, options = {}) {
   throwIfInstancesThrew(vm)
 
   const wrapperOptions = {
-    attachedToDocument: !!mergedOptions.attachToDocument,
-    sync
+    attachedToDocument: !!mergedOptions.attachToDocument
   }
 
   const root = parentVm.$options._isFunctionalContainer