Error: zone-testing.js is needed for the fakeAsync() test helper but could not be found. When running test on Angular webapp using serenityJS+Jasmine

Question

I am trying to run component testing on Angular web app using serenityJS + Jasmine but encountered the error below. Any idea how I can resolve this issue?

Message:

Error: zone-testing.js is needed for the fakeAsync() test helper but could not be found. Please make sure that your environment includes zone.js/dist/zone-testing.js Stack:

   Error: zone-testing.js is needed for the fakeAsync() test helper but could not be found.
           Please make sure that your environment includes zone.js/dist/zone-testing.js
       at resetFakeAsyncZone (C:\Users\zhenweiwong\Desktop\serenityjsframework\packages\core\testing\src\fake_async.ts:25:9)
       at UserContext.<anonymous> (C:\Users\zhenweiwong\Desktop\serenityjsframework\packages\core\testing\src\before_each.ts:26:5)
       at <Jasmine>
       at processImmediate (internal/timers.js:439:21)
       at process.topLevelDomainCallback (domain.js:131:23)
 Message:
   Error: In this configuration Angular requires Zone.js
 Stack:
   Error: In this configuration Angular requires Zone.js
       at new NgZone (C:\Users\zhenweiwong\Desktop\serenityjsframework\packages\core\src\zone\ng_zone.ts:129:13)
       at TestBedViewEngine._initIfNeeded (C:\Users\zhenweiwong\Desktop\serenityjsframework\packages\core\testing\src\test_bed.ts:409:9)
       at TestBedViewEngine.createComponent (C:\Users\zhenweiwong\Desktop\serenityjsframework\packages\core\testing\src\test_bed.ts:599:10)
       at Function.TestBedViewEngine.createComponent (C:\Users\zhenweiwong\Desktop\serenityjsframework\packages\core\testing\src\test_bed.ts:245:36)     
       at UserContext.<anonymous> (C:\Users\zhenweiwong\Desktop\serenityjsframework\jasmine-test\spec\app1.component.spec.ts:32:29)
       at <Jasmine>

Answer 1

Angular 15

I ended up here after getting a similar issue in my app after upgrading from Angular 14 to Angular 15. I solved it this way by:

1. editing the angular.json file and in the project "test" changing its "options" by removing "main": "src/test.ts", and adding this instead:

"polyfills": ["zone.js", "zone.js/testing"],

2. the src/test.ts file can now be deleted

Answer 2

I solved this problem by using Angular waitForAsync.

Instead of:

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

Try to use the following:

import { waitForAsync } from '@angular/core/testing';

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

Answer 3

Hello little bit late to answer but I leave the comment here for future reference:

ERROR ORIGIN

In my case, the error was found in the test.ts file. This file sets the TestBed config that is used by default in Angular spec files when created with the command ng generate component my-component.

SOLUTION

The fix is to make sure that you place the following imports at the TOP of the file test.ts before any other import:

// Top of test.ts file
import 'zone.js';
import 'zone.js/testing';

Be careful with your configurations that might alter the order of those imports as it may lead to break the tests again. That's why you might, over the test.ts file:

1. Deactivate onSave optimize imports.
2. Avoid running Prettier, Beautify or other code style formatter that reorganizes the imports.
3. Check for pre-commits hooks like Husky that format the files and reorganize the imports.

FURTHER TROUBLESHOTING

You might also want to look if the following imports are present:

import 'zone.js';
import 'zone.js/dist/async-test.js';
import 'zone.js/dist/proxy.js';
import 'zone.js/dist/sync-test';
import 'zone.js/dist/jasmine-patch';

Same issue was solved with other approaches in this thread.

Answer 4

I got the same issue after upgraded from the Angular 10 to Angular 12. Then I fixed it by move the import 'zone.js/testing to the top of the file test.ts

Answer 5

This issue comes into picture from Angular v11.

Solution: Move import 'zone.js/dist/zone-testing'; to the top in src/test.ts file.

Answer 6

In Vscode open file test.ts.

Add line down on top file, first line.

import 'zone.js/testing';

OBS: if your vscode organize your imports there file, use o organize-imports-disable-next-line.

Example:

import 'zone.js/testing';
// organize-imports-disable-next-line

See more

Answer 7

For me this error because of syntax,

From

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

To

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

Answer 8

I fixed the same issue by adding import 'jest-preset-angular/setup-jest'; in setupJest.ts which is used in jest.config.js:

module.exports = {
  preset: './jest.preset.js',
  setupFilesAfterEnv: [
    "<rootDir>/setupJest.ts"
  ],
...

I am using Angular 14 with Jest@^28.1.3