test: add cypress for e2e test

circle.yml

@@ -2,7 +2,7 @@ version: 2
 jobs:
   build:
     docker:
-      - image: circleci/node:latest
+      - image: circleci/node:latest-browsers
     branches:
       ignore:
         - gh-pages # list of branches to ignore

cypress.json

@@ -0,0 +1 @@
+{}

cypress/fixtures/example.json

@@ -0,0 +1,5 @@
+{
+  "name": "Using fixtures to represent data",
+  "email": "hello@cypress.io",
+  "body": "Fixtures are a great way to mock data for responses to routes"
+}

cypress/integration/spec.js

@@ -0,0 +1,16 @@
+describe('My First Test', () => {
+  it('Does not do much!', () => {
+    cy.visit('http://localhost:4000')
+    cy.wait(1000)
+    cy.window().then(({ pages }) => {
+      expect([...pages]).to.deep.equal([1, 2, 3])
+    })
+    cy.get('#bottom').then($ => {
+      $[0].scrollIntoView()
+    })
+    cy.wait(1000)
+    cy.window().then(({ pages }) => {
+      expect([...pages]).to.deep.equal([1, 2, 3, 4, 5, 6])
+    })
+  })
+})

cypress/plugins/index.js

@@ -0,0 +1,17 @@
+// ***********************************************************
+// This example plugins/index.js can be used to load plugins
+//
+// You can change the location of this file or turn off loading
+// the plugins file with the 'pluginsFile' configuration option.
+//
+// You can read more here:
+// https://on.cypress.io/plugins-guide
+// ***********************************************************
+
+// This function is called when a project is opened or re-opened (e.g. due to
+// the project's config changing)
+
+module.exports = () => {
+  // `on` is used to hook into various events Cypress emits
+  // `config` is the resolved Cypress config
+}

cypress/support/commands.js

@@ -0,0 +1,25 @@
+// ***********************************************
+// This example commands.js shows you how to
+// create various custom commands and overwrite
+// existing commands.
+//
+// For more comprehensive examples of custom
+// commands please read more here:
+// https://on.cypress.io/custom-commands
+// ***********************************************
+//
+//
+// -- This is a parent command --
+// Cypress.Commands.add("login", (email, password) => { ... })
+//
+//
+// -- This is a child command --
+// Cypress.Commands.add("drag", { prevSubject: 'element'}, (subject, options) => { ... })
+//
+//
+// -- This is a dual command --
+// Cypress.Commands.add("dismiss", { prevSubject: 'optional'}, (subject, options) => { ... })
+//
+//
+// -- This is will overwrite an existing command --
+// Cypress.Commands.overwrite("visit", (originalFn, url, options) => { ... })

cypress/support/index.js

@@ -0,0 +1,20 @@
+// ***********************************************************
+// This example support/index.js is processed and
+// loaded automatically before your test files.
+//
+// This is a great place to put global configuration and
+// behavior that modifies Cypress.
+//
+// You can change the location of this file or turn off
+// automatically serving support files with the
+// 'supportFile' configuration option.
+//
+// You can read more here:
+// https://on.cypress.io/configuration
+// ***********************************************************
+
+// Import commands.js using ES2015 syntax:
+import './commands'
+
+// Alternatively you can use CommonJS syntax:
+// require('./commands')

example/index.js

@@ -5,6 +5,8 @@ import RoutePrefetch from '../src'
 Vue.use(Router)
 Vue.use(RoutePrefetch)
 
+window.pages = new Set()
+
 const Nav = {
   render() {
     return (
@@ -20,7 +22,7 @@ const Nav = {
             <router-link to="/page/3">page 3</router-link>
           </li>
         </ul>
-        <ul style="margin-top: 110vh;">
+        <ul style="margin-top: 110vh;" id="bottom">
           <li>
             <router-link to="/page/4" prefetchFiles={['/foo']}>
               page 4
@@ -46,6 +48,7 @@ const Nav = {
 
 const createPage = id => async () => {
   console.log(`fetching page ${id}`)
+  window.pages.add(id)
   return {
     render() {
       return (

package.json

@@ -8,12 +8,15 @@
     "dist"
   ],
   "scripts": {
-    "test": "npm run lint",
+    "test": "npm run lint && npm run test:e2e",
     "lint": "xo",
     "build": "bili --format esm,cjs,esm-min --minimal",
     "prepublishOnly": "npm run build",
     "example": "poi example/index.js --serve --jsx vue",
-    "commit": "git-cz"
+    "commit": "git-cz",
+    "cy:run": "cypress run",
+    "cy:open": "cypress open",
+    "test:e2e": "run-p --race example cy:run"
   },
   "repository": {
     "url": "egoist/vue-router-prefetch",
@@ -25,13 +28,16 @@
     "babel-eslint": "^10.0.1",
     "bili": "^4.0.9",
     "commitizen": "^3.0.5",
+    "cypress": "^3.3.2",
     "cz-conventional-changelog": "^2.1.0",
     "eslint-config-prettier": "^3.3.0",
     "eslint-config-rem": "^4.0.0",
+    "eslint-plugin-cypress": "^2.2.1",
     "eslint-plugin-prettier": "^3.0.0",
     "eslint-plugin-vue": "^5.1.0",
     "husky": "^1.0.0-rc.13",
     "lint-staged": "^7.2.0",
+    "npm-run-all": "^4.1.5",
     "poi": "^12.4.6",
     "prettier": "^1.15.2",
     "semantic-release": "^15.13.3",
@@ -52,12 +58,17 @@
       "plugin:prettier/recommended"
     ],
     "envs": [
-      "browser"
+      "browser",
+      "cypress/globals"
     ],
     "rules": {
       "no-new": "off",
-      "no-unused-expressions": "off"
-    }
+      "no-unused-expressions": "off",
+      "import/no-unassigned-import": "off"
+    },
+    "plugins": [
+      "cypress"
+    ]
   },
   "husky": {
     "hooks": {