How to run unit tests in a VSTS CI build with Angular 5 and PhantomJS Part 1

Setting up Angular 5 project

You chose Angular 5 as FrontEnd framework, and you made a good choice!

As you can see, Angular 5 comes with Angular-CLI 1.5.

Angular-CLI  npm package installs Angular 5 as we said before and also a complete unit tests toolset :

  • Karma
  • Jasmine

Karma is a Javascript test runner, and Jasmine is a behavior-driven development framework for testing JavaScript code.

In this article I won’t describe how they work, but i will describe how to use then in a VSTS CI.

The critical phase we encounter is how unit tests are run: Karma need a browser to run units tests with Jasmine .

With Angular-CLI there is no issue with that because when you launch your tests with :

ng test

Karma launches automatically a browser like this :

Now we want to build a CI in VSTS but, there is no browser! what can we do ?

PhantomJS is here to help us!

PhantomJS is a so called Headless Browser (or headless WebKit scriptable, as they call it themselves). A headless browser is a browser that is just running in the background, that you can only interact with via code or a terminal. This is just what we need, so let’s make our test run on Phantom instead of Chrome.


how does it work ?

Let’s install it and set up in our Angular 5 project!

Step 1, install PhantomJS itself and its runner for Karma

npm install phantomjs-prebuilt --save-dev
npm install karma-phantomjs-launcher --save-dev

Step 2, add them by modifying karma.conf.js

Add karma-phantomjs-launcher in plugins array :

plugins: [

Step 3, uncomment the big pollyfils block in pollyfils.ts :

import 'core-js/es6/symbol';
import 'core-js/es6/object';
import 'core-js/es6/function';
import 'core-js/es6/parse-int';
import 'core-js/es6/parse-float';
import 'core-js/es6/number';
import 'core-js/es6/math';
import 'core-js/es6/string';
import 'core-js/es6/date';
import 'core-js/es6/array';
import 'core-js/es6/regexp';
import 'core-js/es6/map';
import 'core-js/es6/weak-map';
import 'core-js/es6/set';

import 'intl'
import 'intl/locale-data/jsonp/en'

Step 4, Add a ng test script in package.json :

"scripts": {
 "ng": "ng",
 "start": "ng serve",
 "build": "ng build",
 "test": "ng test",
 "lint": "ng lint",
 "e2e": "ng e2e",
"test-single-headless": "ng test --single-run=true --browsers=PhantomJS --reporters=progress"

We are done for the PhantomJS setting up! 🙂

Let’s take a look on VSTS configuration for CI

Written by


Anthony is a specialist in Web technologies (14 years of experience), in particular Microsoft .NET and learns the Cloud Azure platform. He has received twice the Microsoft MVP award and he is also certified Microsoft MCSD and Azure Fundamentals.
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