Mocha and Chai are popular JavaScript testing frameworks. Mocha is a feature-rich testing framework that runs tests on Node.js and browsers, simplifies asynchronous testing, and supports test-driven development and behavior-driven development. It works with any mocking library and supports file watching. Chai provides three different assertion styles (should, expect, assert) and works on Node.js and browsers. The document provides instructions on setting up Mocha and Chai with Node.js including installing them with NPM and configuring test file locations and running tests.

1. JavaScript Testing
With Mocha and Chai

2. What we have?
• QUnit
• Mocha
• YUITest
• Jasmine
• JSUnit
• Suitest
• Sinon.js
• DOH
• Enhance JS
• RhUnit
• ….

3. Why Mocha?
• Client side
• Server side
• Well maintained
• Well documented
• Integration with CI
• We can choose desired assertion library

4. Mocha

5. Mocha
• Feature Rich
• Runs on node + the browser
• Simplifies async testing
• Supports TDD/BDD
• Choose any Mocking library
• File watcher support

6. Chai
• BBD / TDD
• For node + the browser
• Three assertion styles
• should - foo.should.be.a(‘string’)
• expect - expect(foo).to.be.a(‘string’)
• assert - assert.typeOf(foo,‘string’)

7. Getting started
• Requires node
• Requires npm
• npm install -g mocha
• npm install -g chai

8. Setup
• Expects tests to be in <project_root>/test
• Allows of per project options file:
• mocha.opts
• To run test:
• mocha

9. First test
describe('Array', function() {
describe('#indexOf()', function() {
it('should return -1 when the value is not present', function() {
[1,2,3].indexOf(5).should.equal(-1);
[1,2,3].indexOf(0).should.equal(-1);
})
})
})

10. Hooks
• before()
• after()
• beforeEach()
• AfterEach()

11. Hooks
describe('Array', function() {
before(function() {
});
after(function(){
});
})

12. Thanks!