Usage of spec.js file in AngularJS

Question

This might sound a stupid question, but I want to know its answer. What is the spec.js file in AngularJS and what is its use? Is it used for testing purpose?

EDIT- Below is the code of file phone-detail.component.spec.js

'use strict';  describe('phoneDetail', function() {    // Load the module that contains the `phoneDetail` component before each test   beforeEach(module('phoneDetail'));    // Test the controller   describe('PhoneDetailController', function() {     var $httpBackend, ctrl;     var xyzPhoneData = {       name: 'phone xyz',       images: ['image/url1.png', 'image/url2.png']     };      beforeEach(inject(function($componentController, _$httpBackend_, $routeParams) {       $httpBackend = _$httpBackend_;       $httpBackend.expectGET('phones/xyz.json').respond(xyzPhoneData);        $routeParams.phoneId = 'xyz';        ctrl = $componentController('phoneDetail');     }));      it('should fetch the phone details', function() {       jasmine.addCustomEqualityTester(angular.equals);        expect(ctrl.phone).toEqual({});        $httpBackend.flush();       expect(ctrl.phone).toEqual(xyzPhoneData);     });    });  }); 

Answer 1

Use of spec.js is for writing you unit test cases for your angular application. We write test cases in angular using Jasmine & Karma.

Jasmine is a Behavior Driven Development testing framework for JavaScript. It does not rely on browsers, DOM, or any JavaScript framework. Thus it's suited for websites, Node.js projects, or anywhere that JavaScript can run.

https://github.com/jasmine/jasmine

Karma is essentially a tool which spawns a web server that executes source code against test code for each of the browsers connected. The results of each test against each browser are examined and displayed via the command line to the developer such that they can see which browsers and tests passed or failed.

https://karma-runner.github.io/1.0/index.html