fix: refactor Vue initialization in app frame

Refactors how the Vue instance within the component app frame is initialized, and fully fixes Vue integration.
- fixes lingering issues after pull request cypress-io#13
- fully fixes cypress-io#6
- fixes #1
- README docs have been updated to reflect refactoring
- 'vue' option has been deprecated (with warning to user) as it's no longer necessary
- spread operator support has been added for upcoming Vuex example

Author: amirrustam

README.md

@@ -45,13 +45,11 @@ See examples below for details.
 See [cypress/integration/options-spec.js](cypress/integration/options-spec.js)
 for examples of options.
 
-* `vue` - path or URL to the Vue library to load. By default, will
-try to load `../node_modules/vue/dist/vue.js`, but you can pass your
-own path or URL.
+* `mountId` - specify root Vue app mount element ID. Defaults to `app`.
 
 ```js
 const options = {
-  vue: 'https://unpkg.com/vue'
+  mountId: 'rootApp'  // div#rootApp
 }
 beforeEach(mountVue(/* my Vue code */, options))
 ```
@@ -71,12 +69,25 @@ beforeEach(mountVue(/* my Vue code */, options))
 place to load additional libraries, polyfills and styles.
 
 ```js
-const vue = '../node_modules/vue/dist/vue.js'
+const polyfill = '../node_modules/mypolyfill/dist/polyfill.js'
 const options = {
-  html: `<div id="app"></div><script src="${vue}"></script>`
+  html: `<div id="app"></div><script src="${polyfill}"></script>`
+}
+beforeEach(mountVue(/* my Vue code */, options))
+```
+
+* `vue` **[DEPRECATED]** - path or URL to the Vue library to load. By default, will
+try to load `../node_modules/vue/dist/vue.js`, but you can pass your
+own path or URL.
+
+```js
+const options = {
+  vue: 'https://unpkg.com/vue'
 }
 beforeEach(mountVue(/* my Vue code */, options))
 ```
+> #### Deprecation Warning
+> `vue` option has been deprecated. `node_modules/vue/dist/vue` is always used.
 
 ### Global Vue extensions
 

components/.babelrc

@@ -0,0 +1,5 @@
+{
+  "plugins": [
+    "transform-object-rest-spread"
+  ]
+}

package.json

@@ -71,6 +71,7 @@
     "generateNotes": "github-post-release"
   },
   "devDependencies": {
+    "babel-plugin-transform-object-rest-spread": "6.26.0",
     "ban-sensitive-files": "1.9.2",
     "css-loader": "0.28.7",
     "cypress": "1.4.1",
@@ -86,7 +87,6 @@
     "semantic-action": "1.1.0",
     "simple-commit-message": "3.3.2",
     "standard": "10.0.3",
-    "vue": "2.5.13",
     "vue-loader": "13.6.1",
     "vue-template-compiler": "2.5.13",
     "vuex": "3.0.1"
@@ -100,6 +100,7 @@
   },
   "dependencies": {
     "@cypress/webpack-preprocessor": "1.1.2",
-    "common-tags": "1.6.0"
+    "common-tags": "1.6.0",
+    "vue": "2.5.13"
   }
 }

src/index.js

@@ -1,5 +1,17 @@
+const Vue = require('vue/dist/vue')
 const { stripIndent } = require('common-tags')
 
+// mountVue options
+const defaultOptions = ['html', 'vue', 'base', 'mountId', 'extensions']
+
+// default mount point element ID for root Vue instance
+const defaultMountId = 'app'
+
+const parentDocument = window.parent.document
+const projectName = Cypress.config('projectName')
+const appIframeId = `Your App: '${projectName}'`
+const appIframe = parentDocument.getElementById(appIframeId)
+
 // having weak reference to styles prevents garbage collection
 // and "losing" styles when the next test starts
 const stylesCache = new Map()
@@ -23,10 +35,6 @@ const copyStyles = component => {
     return
   }
 
-  const parentDocument = window.parent.document
-  const projectName = Cypress.config('projectName')
-  const appIframeId = `Your App: '${projectName}'`
-  const appIframe = parentDocument.getElementById(appIframeId)
   const head = appIframe.contentDocument.querySelector('head')
   styles.forEach(style => {
     head.appendChild(style)
@@ -42,59 +50,20 @@ const deleteCachedConstructors = component => {
   Cypress._.values(component.components).forEach(deleteConstructor)
 }
 
-const getVuePath = options =>
-  options.vue || options.vuePath || '../node_modules/vue/dist/vue.js'
-
-const getVuexPath = options => options.vuex || options.vuexPath
-
 const getPageHTML = options => {
-  if (options.html) {
-    return options.html
-  }
-  const vue = getVuePath(options)
-  let vuex = getVuexPath(options)
-  if (vuex) {
-    vuex = `<script src="${vuex}"></script>`
-  }
-
-  // note: add "base" tag to force loading static assets
-  // from the server, not from the "spec" file URL
-  if (options.base) {
-    if (vue.startsWith('.')) {
-      console.error(
-        'You are using base tag %s and relative Vue path %s',
-        options.base,
-        vue
-      )
-      console.error('the relative path might NOT work')
-      console.error(
-        'maybe pass Vue url using "https://unpkg.com/vue/dist/vue.js"'
-      )
-    }
-    return stripIndent`
-      <html>
-        <head>
-          <base href="${options.base}" />
-        </head>
-        <body>
-          <div id="app"></div>
-          <script src="${vue}"></script>
-        </body>
-      </html>
-    `
-  }
-
-  const vueHtml = stripIndent`
+  return (
+    options.html ||
+    stripIndent`
     <html>
-      <head></head>
+      <head>
+        ${options.base ? `<base href="${options.base}" />` : ''}
+      </head>
       <body>
-        <div id="app"></div>
-        <script src="${vue}"></script>
-        ${vuex || ''}
+        <div id="${options.mountId || defaultMountId}"></div>
       </body>
     </html>
   `
-  return vueHtml
+  )
 }
 
 const registerGlobalComponents = (Vue, options) => {
@@ -128,18 +97,16 @@ const installMixins = (Vue, options) => {
   }
 }
 
-const isOptionName = name =>
-  ['vue', 'html', 'vuePath', 'base', 'extensions'].includes(name)
+const isOptionName = name => defaultOptions.includes(name)
 
 const isOptions = object => Object.keys(object).every(isOptionName)
 
 const isConstructor = object => object && object._compiled
 
 const hasStore = ({ store }) => store && store._vm
 
-const forEachValue = (obj, fn) => {
+const forEachValue = (obj, fn) =>
   Object.keys(obj).forEach(key => fn(obj[key], key))
-}
 
 const resetStoreVM = (Vue, { store }) => {
   // bind store public getters
@@ -177,38 +144,51 @@ const mountVue = (component, optionsOrProps = {}) => () => {
     props = optionsOrProps
   }
 
-  const vueHtml = getPageHTML(options)
-  const document = cy.state('document')
-  document.write(vueHtml)
-  document.close()
-
-  // TODO: do not log out "its(Vue)" command
-  // but it currently does not support it
-  return cy
-    .window({ log: false })
-    .its('Vue')
-    .then(Vue => {
-      // refresh inner Vue instance of Vuex store
-      if (hasStore(component)) {
-        component.store = resetStoreVM(Vue, component)
-      }
-      installMixins(Vue, options)
-      installPlugins(Vue, options)
-      registerGlobalComponents(Vue, options)
-      deleteCachedConstructors(component)
-
-      if (isConstructor(component)) {
-        const Cmp = Vue.extend(component)
-        Cypress.vue = new Cmp(props).$mount('#app')
-        copyStyles(Cmp)
-      } else {
-        const allOptions = Object.assign({}, component, { el: '#app' })
-        Cypress.vue = new Vue(allOptions)
-        copyStyles(component)
-      }
-
-      return Cypress.vue
-    })
+  // display deprecation warnings
+  if (options.vue) {
+    console.warn(stripIndent`
+      [DEPRECATION]: 'vue' option has been deprecated.
+      'node_modules/vue/dis/vue' is always used.
+      Please remove it from your 'mountVue' options.`)
+  }
+
+  // insert base app template
+  const doc = appIframe.contentDocument
+  doc.write(getPageHTML(options))
+  doc.close()
+
+  // get root Vue mount element
+  const mountId = options.mountId || defaultMountId
+  const el = doc.getElementById(mountId)
+
+  // set global Vue instance:
+  // 1. convenience for debugging in DevTools
+  // 2. some libraries might check for this global
+  appIframe.contentWindow.Vue = Vue
+
+  // refresh inner Vue instance of Vuex store
+  if (hasStore(component)) {
+    component.store = resetStoreVM(Vue, component)
+  }
+
+  // setup Vue instance
+  installMixins(Vue, options)
+  installPlugins(Vue, options)
+  registerGlobalComponents(Vue, options)
+  deleteCachedConstructors(component)
+
+  // create root Vue component
+  // and make it accessible via Cypress.vue
+  if (isConstructor(component)) {
+    const Cmp = Vue.extend(component)
+    Cypress.vue = new Cmp(props).$mount(el)
+    copyStyles(Cmp)
+  } else {
+    Cypress.vue = new Vue(component).$mount(el)
+    copyStyles(component)
+  }
+
+  return cy.wrap(Cypress.vue)
 }
 
 module.exports = mountVue