JEST: Testing Framework Guillermo Fernndez-Campoamor Fernndez - PowerPoint PPT Presentation

JEST: Testing Framework Guillermo Fernández-Campoamor Fernández Carlos Manrique Enguita Elena Rodríguez Río Diego Ramírez Amandi

WHAT IS JEST? Jest is a JavaScript testing framework that focus on simplicity

HOW TO USE JEST? 1 yarn add --dev jest • npm install --save-dev jest • 2 { "scripts": { "test": "jest" } } yarn test • 3 npm run test •

Jest Functionalities • Testing asynchronous code toBe • toBeTruthy • toEqual • • Setup and Teardown toBeFalsy • not.ToBe • toMatch • toBeNull • toContain • ToBeDefine • • Matchers expect(2+2).toBe(4); <a className="normal" href="http://www.facebook.com" • Mock functions onMouseEnter={[Function]} onMouseLeave={[Function]} > Facebook </a> • Snapshop Testing const tree = renderer.create(< Link page="http://www.facebook.com"> Facebook</ Link >) .toJSON(); expect(tree).toMatchSnapshot();

STAKEHOLDERS

Contributors STAKEHOLDERS 1 Final Users • Helping solving issues on Jest Open-Source Community • open github repository Facebook • Dev Team • Sponsors • 2 Users giving money to the dev team through donations or promoting to Backer role. 3 Sponsors

Main Focus of Interest Developer Dev Team Community Money Contributions

ANYONE CAN CONTRIBUTE TO THE PROJECT

ANYONE CAN CONTRIBUTE TO THE PROJECT

ANYONE CAN CONTRIBUTE TO THE PROJECT

EVEN YOU

QUALITY ATTRIBUTES

QUALITY ATTRIBUTES 1 PERFORMANCE EFFICIENCY We want good performance for our tests 2 MAINTAINABILITY Save costs RELIABILITY 3 Tests must be trustable

JEST ARCHITECTURE

How is the code organized?

1 Jest-cli 7 jest SearchSource 8 Jest-config 3 2 TestSequencer 9 6 Jest-haste-map TestScheduler watchmen 10 5 4 Jest-runner Jest-worker Jest-worker puppeter 11 12 Jest-jasmine2 Jest-runtime vm Jest-circus Jest-environment

1 Jest-cli 7 jest SearchSource 8 Jest-config 3 2 TestSequencer 9 6 Jest-haste-map TestScheduler watchmen The testing 10 5 4 Jest-runner Jest-worker Jest-worker Prior to the puppeter 11 test itself 12 Jest-jasmine2 Jest-runtime vm Jest-circus Jest-environment

1 Jest-cli 7 jest SearchSource 8 Jest-config 3 2 TestSequencer 9 6 Jest-haste-map TestScheduler watchmen 10 5 4 Jest-runner Jest-worker Jest-worker puppeter 11 12 Prior to the Jest-jasmine2 Jest-runtime vm Jest-circus test itself Jest-environment

1 Jest-cli 7 jest SearchSource 8 Jest-config 3 2 TestSequencer 9 6 Jest-haste-map TestScheduler watchmen 10 5 4 Jest-runner Jest-worker Jest-worker puppeter 11 The testing 12 Jest-jasmine2 Jest-runtime vm Jest-circus Jest-environment

1 Jest-cli 7 jest SearchSource 8 Jest-config 3 2 TestSequencer 9 6 Jest-haste-map TestScheduler watchmen 10 5 4 Jest-runner Jest-worker Jest-worker puppeter 11 The testing 12 Jest-jasmine2 Jest-runtime vm Jest-circus Jest-environment

1 Jest-cli 7 jest SearchSource 8 Jest-config 3 2 TestSequencer 9 6 Jest-haste-map TestScheduler watchmen 10 5 4 Jest-runner Jest-worker Jest-worker puppeter 11 The testing 12 Jest-jasmine2 Jest-runtime vm Jest-circus Jest-environment

CONTRIBUTE

How to contribute Take a look to: • Facebook Open Source CoC • Contributing guide of Jest

Other considerations Code conventions: 2 spaces for indentation • 80 char line length • ‘ over “ • Use TypeScript • … •

COMPILE JEST

How do we compile Jest? Install: Yarn • Python (2.7) • Node.js (12.x) • Run OR yarn link jest-cli yarn unlink jest-cli

JEST COMMUNITY

Jest Community and extensions

Visual Studio Code extension Features Starts Jest automatically Show individual fail / passes inline Highlights the errors next to the expect functions Help debug jest tests in vscode

Jest-extended Provides new matchers (assertions) to ease testing npm install --save-dev jest-extended

CONCLUSION