Angular Jasmine Filter Unit Test (SO Docs)

by Wojciech Frącz

HTML

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/jasmine/2.4.1/jasmine.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/jasmine/2.4.1/jasmine.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jasmine/2.4.1/jasmine-html.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jasmine/2.4.1/boot.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.5.8/angular.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.5.8/angular-mocks.js"></script>

JavaScript

angular.module('myModule', []).filter('multiplier', function() {
  return function(number, multiplier) {
    if (!angular.isNumber(number)) {
      throw new Error(number + " is not a number!");
    }
    if (!multiplier) {
      multiplier = 2;
    }
    return number * multiplier;
  }
});

describe('multiplierFilter', function() {
  var filter;

  beforeEach(function() {
    module('myModule');
    inject(function(multiplierFilter) {
      filter = multiplierFilter;
    });
  });

  it('multiply by 2 by default', function() {
    expect(filter(2)).toBe(4);
    expect(filter(3)).toBe(6);
  });

  it('allow to specify custom multiplier', function() {
    expect(filter(2, 4)).toBe(8);
  });

  it('throws error on invalid input', function() {
    expect(function() {
      filter(null);
    }).toThrow();
  });
});