@theintern/angular-plugin

A plugin to set up the Angular testbed for use with Intern

Installation

@theintern/angular-plugin should be installed as a peer of intern:

npm install intern@next @theintern/angular-plugin

Usage

To use @theintern/angular-plugin, simply add it to the plugins array of intern.json:

{
  "browser": {
    ...

    "plugins": [
      "@theintern/angular-plugin"
    ],

    ...
  }
}

The plugin does the following:

• Ensures Zone.js is loaded with long stack trace support
• Initializes Angular's TestBed for use in the browser
• Resets the testing module of Angular's TestBed after each test

If a browser shim or other Zone.js patches are required, add them as plugins before and after @theintern/angular-plugin:

{
  "browser": {
    ...

    "plugins": [
      "core-js/client/shim.js",
      "@theintern/angular-plugin",
      "zone.js/dist/proxy.js",
      "zone.js/dist/sync-test.js",
      "zone.js/dist/async-test.js",
      "zone.js/dist/fake-async-test.js"
    ],

    ...
  }
}

NOTE: Because of Intern's native support of asynchronous tests (and TypeScript's downlevel emit for async/await), there should be no need for the fake async patches to Zone.js.

Writing unit tests

Writing unit tests for Angular in Intern should look similar to writing unit tests for Angular in Karma, with one notable exception: there is no need for the fake async wrappers and async/await should be used instead:

const { describe, it, beforeEach } = intern.getInterface('bdd');
const { expect } = intern.getPlugin('chai');

import { ComponentFixture, TestBed } from '@angular/core/testing';
import { MyComponent } from './MyComponent';

describe('MyComponent', () => {
    let comp: MyComponent;
    let fixture: ComponentFixture<MyComponent>;

    beforeEach(async () => {
        await TestBed.configureTestingModule({
            declarations: [
                ...
            ]
        }).compileComponents();

        fixture = TestBed.createComponent(MyComponent);
        comp = fixture.componentInstance;

        fixture.detectChanges();
    });

    it('is instantiated', () => {
        expect(comp).not.to.be.null;
    });
});