Gleb Bahmutov PRO
JavaScript ninja, image processing expert, software quality fanatic
Gleb Bahmutov, PhD
VP of Engineering
Good News About End-to-end Testing with Open Source
our planet is in imminent danger
https://lizkeogh.com/2019/07/02/off-the-charts/
+3 degrees Celsius will be the end.
we have to act today
ME
you
you
you
you
vote & lobby & rebel
if I can help I will
@bahmutov
gleb.bahmutov@gmail.com
If there is a company that fights global climate catastrophe and needs JavaScript and testing skills - I will do for free.
example: https://fab.earth
Dr Gleb Bahmutov PhD
C / C++ / C# / Java / CoffeeScript / JavaScript / Node / Angular / Vue / Cycle.js / functional
(these slides)
30 people. Atlanta, Philly, Boston, NYC, the world
Fast, easy and reliable testing for anything that runs in a browser
Why is all software broken?
Quality software behaves the way users expect it to behave
We going to need some tests
E2E
integration
unit
Testing Pyramid △
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
$ npm install -D cypress
- Win / Mac / Linux
- MIT License
- OSS https://github.com/cypress-io/cypress
- http://on.cypress.io/introduction-to-cypress
Cypress demo
- Typical test
- Failing test
- Recording tests
- CI setup
- Cypress dashboard
// ui-spec.js
it('loads the app', () => {
cy.visit('http://localhost:3000')
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)
})
$ npx cypress openDOM
storage
location
cookies
Cypress tests run in the same browser
DOM
storage
location
cookies
Cypress acts as a proxy for your app
Tutorials
Api
Examples
-
"cypress open" - GUI interactive mode
-
"cypress run" - headless mode
Cypress CLI has 2 main commands
full video of the run, screenshots of every failure
-
Every CI should be good
-
Or use a Docker image we provide
Running E2E on CI
Making it easy for users is not easy
Paid Features 💵
- recording test artifacts
- test parallelization
- GitHub integration
- (WIP) historical insights
Paid Features 💵
Paid Features 💵: artifacts
test output, video, screenshots
$ npx cypress run --record --parallel
Cypress v3.1.0
Spin N CI machines and
Text
cypress-dashboard parallelization
cypress-dashboard parallelization
Plus component testing
import { HelloState } from '../src/hello-x.jsx'
import React from 'react'
it('changes state', () => {
cy.mount(<HelloState />)
cy.contains('Hello Spider-man!')
const stateToSet = { name: 'React' }
cy.get(HelloState).invoke('setState', stateToSet)
cy.get(HelloState)
.its('state')
.should('deep.equal', stateToSet)
cy.contains('Hello React!')
})Plus code coverage
Plus visual testing
it('draws pizza correctly', function () {
cy.percySnapshot('Empty Pizza')
cy.enterDeliveryInformation()
const toppings = ['Pepperoni', 'Chili', 'Onion']
cy.pickToppings(...toppings)
// make sure the web app has updated
cy.contains('.pizza-summary__total-price', 'Total: $12.06')
cy.percySnapshot(toppings.join(' - '))
})Visual review workflow
<style type="text/css">
.st0{fill:#FFD8A1;}
.st1{fill:#E8C08A;}
- .st2{fill:#FFDC71;}
+ .st2{fill:#71FF71;}
.st3{fill:#DFBA86;}
</style>changes crust color SVG
1. Make pull request with visual changes
Visual review workflow
catch visual changes in the pull request
2. Review & approve visual changes
Visual review workflow
2. Review & approve visual changes
App Actions
// app code
var model = new app.TodoModel('react-todos')
if (window.Cypress) {
window.model = model
}
// test code
export const addTodos = (...todos) => {
cy.window()
.its('model')
.should('be.an', 'object')
.invoke('addTodo', ...todos)
}Why developers love Cypress
-
Fast, flake-free
-
GUI, time travel
-
Test recording
-
Documentation
Coming soon
-
Retries / flake factor
-
Cross-browser
-
Full network stubbing
-
so many more ideas ...
FF, IE11
Thank you 👏
@cypress_io
@bahmutov
Good News About End-to-end Testing with Open Source Cypress.io
By Gleb Bahmutov
Good News About End-to-end Testing with Open Source Cypress.io
Modern day web applications are hard to test. They are dynamic, constantly asking for new data and updating the DOM. They are changing, loading new code as the user browses. They are unpredictable due to network delays and asynchronous UI updates. The existing tools that run outside the browser, sending imperative commands during the test, have hard times keeping up with the apps. Learn how to improve your job performance and reduce stress with Cypress, a less flaky, simpler to understand and debug, open source testing tool with excellent documentation that can be used to write end-to-end tests, run them locally and on CI, and give the entire team confidence that the user will not see a broken application in production.
