Gleb Bahmutov, PhD

VP of Engineering, Cypress.io

Cypress: testing without Selenium

Part 1

C / C++ / C# / Java / CoffeeScript / JavaScript / Node / Angular / Vue / Cycle.js / functional / testing

🖥 🇬🇧

🗣 🇷🇺

❤️ 🇺🇦

18 people. Atlanta, Philly, Boston, Chicago, NYC

Fast, easy and reliable testing for anything that runs in a browser

I have Cypress.io stickers

Why is all software broken?

Will Klein

Contents: Part 1

  • Testing pyramid

  • Testing in real browser

  • Cypress demo

Contents: Part 2

  • Cypress architecture

  • Declarative test syntax

  • Code coverage updates

  • CircleCI Orbs

  • Component and API testing

Quality software behaves the way users expect it to behave

We going to need some tests

E2E

integration

unit

Smallest pieces

Testing Pyramid △

Unit tests pass...

E2E

integration

unit

Component

E2E

integration

unit

Website / API

E2E

integration

unit

Really important to users

Really important to developers

E2E

integration

unit

Web application

  • Open real browser
  • Load actual app
  • Interact with app like a real user
  • See if it works

Let's test!

  1. Open and control real browser

Your tests

Selenium

Driver

FF, Chrome , IE

Let's test!

  1. Open and control real browser

Your tests

Selenium

Driver

FF, Chrome , IE

✅ JavaScript, Java, Python, C#, etc

Let's test!

  1. Open and control real browser

Your tests

Selenium

Driver

FF, Chrome , IE

⚠️ HTTP request

Let's test!

  1. Open and control real browser

Your tests

FF, Chrome , IE

slow, flaky, unreliable tests

Let's test!

Your tests

Headless browser

What is happening?

Cypress vs X

People testing with Selenium / WebDriver

Cypress users?

No E2E tests

E2E should be easy

  • Easy to install

  • Easy to write tests

  • Simple to run

Easy to debug when a test fails

Cypress.io

Electron based cross-platform app

Let's test!

Your tests

Your web app

Cypress App

start

Chrome (for now)

Cypress.io: recommended

Cypress.io: recommended

Learn Node

JavaScript around us

  • Browser

  • Server

  • Desktop

  • Mobile

  • Gray areas:

    • IoT, robots, code snippets, build scripts, sw

JavaScript around us

  • Browser

  • Server

  • Desktop

  • Mobile

  • Gray areas:

    • IoT, robots, code snippets, build scripts, sw

only runs JavaScript

With Node you get NPM

Install Node tools and 3rd party dependencies

# start new Node project
npm init
# add Cypress dependency
npm install --save-dev cypress
# open Cypress
npx cypress open

Cypress.io: recommended

Cross-platform JavaScript environment

another useful tool included in Node

$ npm install -D cypress
npx cypress open

Created folders:

  • integration - with tests
  • support - custom commands
  • plugins - ways to customize Cypress
  • fixtures - JSON mock data

cypress.json - customize Cypress settings

For power users

npx @bahmutov/cly init
// ui-spec.js
it('loads the app', () => {
  cy.visit('http://localhost:3030')
  cy.get('.todoapp').should('be.visible')
})

Mocha BDD syntax

Chai assertions

it('adds 2 todos', () => {
  cy.visit('http://localhost:3000')
  cy.get('.new-todo')
    .type('learn testing{enter}')
    .type('be cool{enter}')
  cy.get('.todo-list li')
    .should('have.length', 2)
})

fluent API like jQuery

it('adds 2 todos', () => {
  cy.visit('http://localhost:3000')
  cy.get('.new-todo')
    .type('learn testing{enter}')
    .type('be cool{enter}')
  cy.get('.todo-list li')
    .should('have.length', 2)
})

assertions

commands

import {resetDatabase} from '../utils'
const visit = () => cy.visit('/')

describe('UI', () => {
  beforeEach(resetDatabase)
  beforeEach(visit)

  context('basic features', () => {
    it('starts with zero items', () => {
      cy.get('.todo-list')
        .find('li')
        .should('have.length', 0)
    })
  })
})

bundling included

base url in cypress.json

cy.request, cy.task, cy.exec

1 * 👀  > 100 * 👂

Cypress demo

  • Typical test
    • point at any server
  • Intelligent code completion
  • Commands and assertions
  • Failing test
  • Videos and screenshots

Cypress demo

  • Custom commands
  • Network control
  • Application access
  • CI setup
  • Cypress dashboard

Cypress Types

types/
  index.d.ts

package.json
  "types": "types"

Explains global "cy" object

User test - just add this comment

Explains "cy.visit" command

Completion for BDD assertions

Completion for specific assertion with examples

IntelliSense-driven development

every command and assertion

links to full docs

inline examples

  1. read docs for hours
  2. go through the tutorial*
  3. read more docs
  4. write tests

New Testing Tool

  1. read "Hello World"
  2. copy to your test
  3. write useful tests
  4. gradually improve

New Testing Tool

Our goal: no matter how well you know JavaScript = you are successfully using Cypress

Giant API

80 commands + events + utilities (lodash, moment, jQuery) + assertions

Every command

  • Syntax
  • Correct usage
  • Incorrect usage
  • Options
  • What it logs
  • Examples and best practices

Tutorials

Api

Examples

Video course

Full workshop

Bonus: JSON IntelliSense

VSCode: in the user settings, global or workspace set:

{
  "json.schemas": [
    {
      "fileMatch": ["cypress.json"],
      "url": "https://on.cypress.io/cypress.schema.json"
    }
  ]
}

VSCode alternative: add "$schema" property to your JSON file

{
  "viewportWidth": 600,
  "viewportHeight": 800,
  "ignoreTestFiles": "answer.js",
  "baseUrl": "http://localhost:3000",
  "$schema": "https://on.cypress.io/cypress.schema.json"
}

Commands and Assertions

BDD / TDD assertions

http://on.cypress.io/assertions

it('adds items', function () {
  cy.get('.new-todo')
    .type('todo A{enter}')
    .type('todo B{enter}')
    .type('todo C{enter}')
    .type('todo D{enter}')
  cy.get('.todo-list li').should('have.length', 2)
})

Command + assertion

command

assertion

it('adds items', function () {
  cy.get('.new-todo')
    .type('todo A{enter}')
    .type('todo B{enter}')
    .type('todo C{enter}')
    .type('todo D{enter}')
  cy.get('.todo-list li', {timeout: 1000000})
    .should('have.length', 2)
})

Retry longer

helping live web application during the test

Test Failed 🎉

Tests are useful when they fail

Test Failed 🎉

Look at the screenshot

Test Failed 🎉

Watch the video

Cypress demo

  • Typical test
    • point at any server
  • Intelligent code completion
  • Commands and assertions
  • Failing test
  • Videos and screenshots

Cypress demo

  • Custom commands
  • Network control
  • Application access
  • CI setup
  • Cypress dashboard

Why developers love Cypress

  • Fast, flake-free

  • GUI, time travel

  • Test recording

  • Documentation

Why developers love Cypress

  • Fast, flake-free

  • GUI, time travel

  • Test recording

  • Documentation

100% FREE & OSS

Where Cypress.io is not there yet

  • Multiple domains

  • Only JavaScript

  • Iframes

End of Part 1

stay for Part 2

Cypress: testing without Selenium Part 1

By Gleb Bahmutov

Cypress: testing without Selenium Part 1

Part 1. Modern web application testing is a hard and ungrateful job. But maybe this is just because we still don’t have a great tool for testing, that could be our friend not enemy? In this talk, I will present you Cypress.io – free test runner made without Selenium or WebDriver. With Cypress you could make your tests quick, simple and useful. Presented at SeleniumCamp in Ukraine, video at https://www.youtube.com/watch?v=hk4qtXgL12k

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