Getting Started and Testing With Angular CLI and Angular 2 (RC5) — Part 2

Continuing on from part one of our tutorial, this section will go over testing and CI in Angular 2 (RC5). Below is a table of contents in case you want to skip right to a particular section.

• Testing
  • Unit test the SearchService
  • Unit test the SearchComponent
  • Integration test the search UI
  • Testing the search feature
  • Testing the edit feature
• Continuous Integration
• Source code
• Summary

Testing

Now that you've built an application, it's important to test it to ensure it works. The best reason for writing tests is to automate your testing. Without tests, you'll likely be testing manually. This manual testing will take longer and longer as your application grows.

In this section, you'll learn to use Jasmine for unit testing controllers and Protractor for integration testing. Angular's testing documentation lists good reasons to test, but doesn't currently have many examples.

Unit Test the SearchService

Modify src/app/shared/search/search.service.spec.ts and setup the test's infrastructure using MockBackend and BaseRequestOptions.

import { MockBackend } from '@angular/http/testing';
import { Http, ConnectionBackend, BaseRequestOptions, Response, ResponseOptions } from '@angular/http';
import { SearchService } from './search.service';
import { tick, fakeAsync } from '@angular/core/testing/fake_async';
import { inject, TestBed } from '@angular/core/testing/test_bed';

describe('SearchService', () => {
  beforeEach(() => {

    TestBed.configureTestingModule({
      providers: [
        {
          provide: Http, useFactory: (backend: ConnectionBackend, defaultOptions: BaseRequestOptions) => {
          return new Http(backend, defaultOptions);
        }, deps: [MockBackend, BaseRequestOptions]
        },
        {provide: SearchService, useClass: SearchService},
        {provide: MockBackend, useClass: MockBackend},
        {provide: BaseRequestOptions, useClass: BaseRequestOptions}
      ]
    });
  });
});

If you run ng test, you will likely see some errors about the test stubs that Angular CLI created for you. You can ignore these for now.

ERROR in [default] /Users/mraible/ng2-demo/src/app/edit/edit.component.spec.ts:10:20
Supplied parameters do not match any signature of call target.

ERROR in [default] /Users/mraible/ng2-demo/src/app/search/search.component.spec.ts:10:20
Supplied parameters do not match any signature of call target.

Add the first test of getAll() to search.service.spec.ts. This test shows how MockBackend can be used to mock results and set the response.

TIP: When you are testing code that returns either a Promise or an RxJS Observable, you can use the fakeAsync helper to test that code as if it were synchronous. Promises are be fulfilled and Observables are notified immediately after you call tick().

The test below should be on the same level as beforeEach.

it('should retrieve all search results',
  inject([SearchService, MockBackend], fakeAsync((searchService: SearchService, mockBackend: MockBackend) => {
    let res: Response;
    mockBackend.connections.subscribe(c => {
      expect(c.request.url).toBe('app/shared/search/data/people.json');
      let response = new ResponseOptions({body: '[{"name": "John Elway"}, {"name": "Gary Kubiak"}]'});
      c.mockRespond(new Response(response));
    });
    searchService.getAll().subscribe((response) => {
      res = response;
    });
    tick();
    expect(res[0].name).toBe('John Elway');
  }))
);

Notice that tests continually run as you add them when using ng test. You can run tests once by using ng test --watch=false. You will likely see "Executed 5 of 5 (1 FAILED)" in your terminal. Add a couple more tests for filtering by search term and fetching by id.

it('should filter by search term',
  inject([SearchService, MockBackend], fakeAsync((searchService: SearchService, mockBackend: MockBackend) => {
    let res;
    mockBackend.connections.subscribe(c => {
      expect(c.request.url).toBe('app/shared/search/data/people.json');
      let response = new ResponseOptions({body: '[{"name": "John Elway"}, {"name": "Gary Kubiak"}]'});
      c.mockRespond(new Response(response));
    });
    searchService.search('john').subscribe((response) => {
      res = response;
    });
    tick();
    expect(res[0].name).toBe('John Elway');
  }))
);

it('should fetch by id',
  inject([SearchService, MockBackend], fakeAsync((searchService: SearchService, mockBackend: MockBackend) => {
    let res;
    mockBackend.connections.subscribe(c => {
      expect(c.request.url).toBe('app/shared/search/data/people.json');
      let response = new ResponseOptions({body: '[{"id": 1, "name": "John Elway"}, {"id": 2, "name": "Gary Kubiak"}]'});
      c.mockRespond(new Response(response));
    });
    searchService.search('2').subscribe((response) => {
      res = response;
    });
    tick();
    expect(res[0].name).toBe('Gary Kubiak');
  }))
);

Unit Test the SearchComponent

To unit test the SearchComponent, create a MockSearchProvider that has spies. These allow you to spy on functions to check if they were called.

Create src/app/shared/search/mocks/search.service.ts and populate it with spies for each method, as well as methods to set the response and subscribe to results.

import { SpyObject } from './helper';
import { SearchService } from '../search.service';
import Spy = jasmine.Spy;

export class MockSearchService extends SpyObject {
  getAllSpy: Spy;
  getByIdSpy: Spy;
  searchSpy: Spy;
  saveSpy: Spy;
  fakeResponse: any;

  constructor() {
    super( SearchService );

    this.fakeResponse = null;
    this.getAllSpy = this.spy('getAll').andReturn(this);
    this.getByIdSpy = this.spy('get').andReturn(this);
    this.searchSpy = this.spy('search').andReturn(this);
    this.saveSpy = this.spy('save').andReturn(this);
  }

  subscribe(callback: any) {
    callback(this.fakeResponse);
  }

  setResponse(json: any): void {
    this.fakeResponse = json;
  }
}

In this same directory, create a helper.ts class to implement the SpyObject that MockSearchService extends.

import {StringMapWrapper} from '@angular/core/src/facade/collection';

export interface GuinessCompatibleSpy extends jasmine.Spy {
  /** By chaining the spy with and.returnValue, all calls to the function will return a specific
   * value. */
  andReturn(val: any): void;
  /** By chaining the spy with and.callFake, all calls to the spy will delegate to the supplied
   * function. */
  andCallFake(fn: Function): GuinessCompatibleSpy;
  /** removes all recorded calls */
  reset();
}

export class SpyObject {
  static stub(object = null, config = null, overrides = null) {
    if (!(object instanceof SpyObject)) {
      overrides = config;
      config = object;
      object = new SpyObject();
    }

    let m = StringMapWrapper.merge(config, overrides);
    StringMapWrapper.forEach(m, (value, key) => { object.spy(key).andReturn(value); });
    return object;
  }

  constructor(type = null) {
    if (type) {
      for (let prop in type.prototype) {
        let m = null;
        try {
          m = type.prototype[prop];
        } catch (e) {
          // As we are creating spys for abstract classes,
          // these classes might have getters that throw when they are accessed.
          // As we are only auto creating spys for methods, this
          // should not matter.
        }
        if (typeof m === 'function') {
          this.spy(prop);
        }
      }
    }
  }

  spy(name) {
    if (!this[name] {
      this[name] = this._createGuinnessCompatibleSpy(name);
    }
    return this[name];
  }

  prop(name, value) { this[name] = value; }

  /** @internal */
  _createGuinnessCompatibleSpy(name): GuinessCompatibleSpy {
    let newSpy: GuinessCompatibleSpy = <any>jasmine.createSpy(name);
    newSpy.andCallFake = <any>newSpy.and.callFake;
    newSpy.andReturn = <any>newSpy.and.returnValue;
    newSpy.reset = <any>newSpy.calls.reset;
    // revisit return null here (previously needed for rtts_assert).
    newSpy.and.returnValue(null);
    return newSpy;
  }
}

Alongside, create routes.ts to mock Angular's Router and ActivatedRoute.

import { ActivatedRoute, Params } from '@angular/router';
import { Observable } from 'rxjs';

export class MockActivatedRoute extends ActivatedRoute {
  params: Observable<Params>

  constructor(parameters?: { [key: string]: any; }) {
    super();
    this.params = Observable.of(parameters);
  }
}

export class MockRouter {
  navigate = jasmine.createSpy('navigate');
}

With mocks in place, you can TestBed.configureTestingModule() to setup SearchComponent to use these as providers.

import { ActivatedRoute, Router } from '@angular/router';
import { MockActivatedRoute, MockRouter } from '../shared/search/mocks/routes';
import { MockSearchService } from '../shared/search/mocks/search.service';
import { SearchComponent } from './search.component';
import { TestBed } from '@angular/core/testing/test_bed';
import { FormsModule } from '@angular/forms';
import { SearchService } from '../shared/search/search.service';

describe('Component: Search', () => {
  let mockSearchService: MockSearchService;
  let mockActivatedRoute: MockActivatedRoute;
  let mockRouter: MockRouter;

  beforeEach(() => {
    mockSearchService = new MockSearchService();
    mockActivatedRoute = new MockActivatedRoute({'term': 'peyton'});
    mockRouter = new MockRouter();

    TestBed.configureTestingModule({
      declarations: [SearchComponent],
      providers: [
        {provide: SearchService, useValue: mockSearchService},
        {provide: ActivatedRoute, useValue: mockActivatedRoute},
        {provide: Router, useValue: mockRouter}
      ],
      imports: [FormsModule]
    });
  });
});

Add two tests, one to verify a search term is used when it's set on the component, and a second to verify search is called when a term is passed in as a route parameter.

it('should search when a term is set and search() is called', () => {
  let fixture = TestBed.createComponent(SearchComponent);
  let searchComponent = fixture.debugElement.componentInstance;
  searchComponent.query = 'M';
  searchComponent.search();
  expect(mockSearchService.searchSpy).toHaveBeenCalledWith('M');
});

it('should search automatically when a term is on the URL', () => {
  let fixture = TestBed.createComponent(SearchComponent);
  fixture.detectChanges();
  expect(mockSearchService.searchSpy).toHaveBeenCalledWith('peyton');
});

After adding these tests, you should see the first instance of all tests passing (Executed 8 of 8 SUCCESS).

Update the test for EditComponent, verifying fetching a single record works. Notice how you can access the component directly with fixture.debugElement.componentInstance, or its rendered version with fixture.debugElement.nativeElement.

import { MockSearchService } from '../shared/search/mocks/search.service';
import { EditComponent } from './edit.component';
import { TestBed } from '@angular/core/testing/test_bed';
import { SearchService } from '../shared/search/search.service';
import { MockRouter, MockActivatedRoute } from '../shared/search/mocks/routes';
import { ActivatedRoute, Router } from '@angular/router';
import { FormsModule } from '@angular/forms';

describe('Component: Edit', () => {
  let mockSearchService: MockSearchService;
  let mockActivatedRoute: MockActivatedRoute;
  let mockRouter: MockRouter;

  beforeEach(() => {
    mockSearchService = new MockSearchService();
    mockActivatedRoute = new MockActivatedRoute({'id': 1});
    mockRouter = new MockRouter();

    TestBed.configureTestingModule({
      declarations: [EditComponent],
      providers: [
        {provide: SearchService, useValue: mockSearchService},
        {provide: ActivatedRoute, useValue: mockActivatedRoute},
        {provide: Router, useValue: mockRouter}
      ],
      imports: [FormsModule]
    });
  });

  it('should fetch a single record', () => {
    const fixture = TestBed.createComponent(EditComponent);

    let person = {name: 'Emmanuel Sanders', address: {city: 'Denver'}};
    mockSearchService.setResponse(person);

    fixture.detectChanges();
    // verify service was called
    expect(mockSearchService.getByIdSpy).toHaveBeenCalledWith(1);

    // verify data was set on component when initialized
    let editComponent = fixture.debugElement.componentInstance;
    expect(editComponent.editAddress.city).toBe('Denver');

    // verify HTML renders as expected
    let compiled = fixture.debugElement.nativeElement;
    expect(compiled.querySelector('h3').innerHTML).toBe('Emmanuel Sanders');
  });
});

You should see "Executed 8 of 8 SUCCESS (0.238 secs / 0.259 secs)" in the shell window that's running ng test. If you don't, try cancelling the command and restarting.

Integration Test the Search UI

To test if the application works end-to-end, you can write tests with Protractor. These are also known as integration tests, since they test the integration between all layers of your application.

To verify end-to-end tests work in the project before you begin, run the following commands in three different console windows.

ng serve
ng e2e

All tests should pass.

$ ng e2e

> ng2-demo@0.0.0 pree2e /Users/mraible/dev/ng2-demo
> webdriver-manager update

Updating selenium standalone to version 2.52.0
downloading https://selenium-release.storage.googleapis.com/2.52/selenium-server-standalone-2.52.0.jar...
Updating chromedriver to version 2.21
downloading https://chromedriver.storage.googleapis.com/2.21/chromedriver_mac32.zip...
chromedriver_2.21mac32.zip downloaded to /Users/mraible/dev/ng2-demo/node_modules/protractor/selenium/chromedriver_2.21mac32.zip
selenium-server-standalone-2.52.0.jar downloaded to /Users/mraible/dev/ng2-demo/node_modules/protractor/selenium/selenium-server-standalone-2.52.0.jar

> ng2-demo@0.0.0 e2e /Users/mraible/dev/ng2-demo
> protractor "config/protractor.conf.js"

[00:01:07] I/direct - Using ChromeDriver directly...
[00:01:07] I/launcher - Running 1 instances of WebDriver
Spec started

  ng2-demo App
     should display message saying app works

Executed 1 of 1 spec SUCCESS in 0.684 sec.
[00:01:09] I/launcher - 0 instance(s) of WebDriver still running
[00:01:09] I/launcher - chrome #01 passed

All end-to-end tests pass.

Testing the Search Feature

Create end-to-end tests in e2e/search.e2e-spec.ts to verify the search feature works. Populate it with the following code:

describe('Search', () => {

  beforeEach(() => {
    browser.get('/search');
    element(by.linkText('Search')).click();
  });

  it('should have an input and search button', () => {
    expect(element(by.css('app-root app-search form input')).isPresent()).toEqual(true);
    expect(element(by.css('app-root app-search form button')).isPresent()).toEqual(true);
  });

  it('should allow searching', () => {
    let searchButton = element(by.css('button'));
    let searchBox = element(by.css('input'));
    searchBox.sendKeys('M');
    searchButton.click().then(() => {
      var list = element.all(by.css('app-search table tbody tr'));
      expect(list.count()).toBe(3);
    });
  });
});

Testing the Edit Feature

Create a e2e/edit.e2e-spec.ts test to verify the EditComponent renders a person's information and that their information can be updated.

describe('Edit', () => {

  beforeEach(() => {
    browser.get('/edit/1');
  });

  let name = element(by.id('name'));
  let street = element(by.id('street'));
  let city = element(by.id('city'));

  it('should allow viewing a person', () => {
    expect(element(by.css('h3')).getText()).toEqual('Peyton Manning');
    expect(name.getAttribute('value')).toEqual('Peyton Manning');
    expect(street.getAttribute('value')).toEqual('1234 Main Street');
    expect(city.getAttribute('value')).toEqual('Greenwood Village');
  });

  it('should allow updating a name', function () {
    let save = element(by.id('save'));
    // send individual characters since sendKeys passes partial values sometimes
    // https://github.com/angular/protractor/issues/698
    ' Won!'.split('').forEach((c) => name.sendKeys(c));
    save.click();
    // verify one element matched this change
    var list = element.all(by.css('app-search table tbody tr'));
    expect(list.count()).toBe(1);
  });
});

Run ng e2e to verify all your end-to-end tests pass. You should see a success message similar to the one below in your terminal window.

If you made it this far and have all your specs passing - congratulations! You're well on your way to writing quality code with Angular 2 and verifying it works.

You can see the test coverage of your project by opening coverage/index.html in your browser. You might notice that the new components and service could use some additional coverage. If you feel the need to improve this coverage, please send me a pull request!

Continuous Integration

At the time of this writing, Angular CLI did not have any continuous integration support. However, it's easy to add with Travis CI. If you've checked in your project to GitHub, you can easily use Travis CI. Simply login and enable builds for the GitHub repo you created the project in. Then add the following .travis.yml in your root directory and git push. This will trigger the first build.

language: node_js
sudo: true

cache:
  directories:
    - node
    - node_modules

dist: trusty

node_js:
  - '5.6.0'

branches:
  only:
  - master

before_install:
 - npm install -g angular-cli
 - export CHROME_BIN=/usr/bin/google-chrome
 - export DISPLAY=:99.0
 - sh -e /etc/init.d/xvfb start
 - sudo apt-get update
 - sudo apt-get install -y libappindicator1 fonts-liberation
 - wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
 - sudo dpkg -i google-chrome*.deb

script:
 - ng test --watch false # http://mseemann.de/frontend/2016/05/31/setup-angular-2-app-part-1.html
 - ng serve &
 - ng e2e

notifications:
  webhooks:
    on_success: change  # options: [always|never|change] default: always
    on_failure: always  # options: [always|never|change] default: always
    on_start: false     # default: false

Here is a build showing all unit and integration tests passing.

Source Code

A completed project with this code in it is available on GitHub at https://github.com/mraible/ng2-demo. If you have ideas for improvements, please leave a comment or send a pull request.

This tutorial was originally written using Asciidoctor. This means you can read it using DocGist if you like.

Summary

I hope you've enjoyed this in-depth tutorial on how to get started with Angular 2 and Angular CLI. Angular CLI takes much of the pain out of setting up an Angular 2 project and using Typescript. I expect great things from Angular CLI, mostly because the Angular 2 setup process can be tedious and CLI greatly simplifies things.