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How to test a multi token in Angular application

If you did not read "How to test a token", please do it first.

Testing multi tokens is quite similar with the difference that TestBet.get returns an array of all providers matching the token.

const values = TestBed.get(TOKEN_MULTI);expect(values).toEqual(jasmine.any(Array));expect(values.length).toEqual(4);

Live example#
import { Injectable, InjectionToken, NgModule } from '@angular/core';import { TestBed } from '@angular/core/testing';import { MockBuilder } from 'ng-mocks';
const TOKEN_MULTI = new InjectionToken('MULTI');
class ServiceClass {  public readonly name = 'class';}
@Injectable()class ServiceExisting {  public readonly name = 'existing';}
// A module that provides all services.@NgModule({  providers: [    ServiceExisting,    {      multi: true,      provide: TOKEN_MULTI,      useClass: ServiceClass,    },    {      multi: true,      provide: TOKEN_MULTI,      useExisting: ServiceExisting,    },    {      multi: true,      provide: TOKEN_MULTI,      useFactory: () => 'FACTORY',    },    {      multi: true,      provide: TOKEN_MULTI,      useValue: 'VALUE',    },  ],})class TargetModule {}
describe('TestMultiToken', () => {  // Because we want to test the token, we pass it as the first  // parameter of MockBuilder. To correctly satisfy its initialization  // we need to pass its module as the second parameter.  // Do not forget to return the promise of MockBuilder.  beforeEach(() => MockBuilder(TOKEN_MULTI, TargetModule));
  it('creates TOKEN_MULTI', () => {    const tokens = TestBed.get(TOKEN_MULTI);
    expect(tokens).toEqual(jasmine.any(Array));    expect(tokens.length).toEqual(4);
    // Verifying that the token is an instance of ServiceClass.    expect(tokens[0]).toEqual(jasmine.any(ServiceClass));    expect(tokens[0].name).toEqual('class');
    // Verifying that the token is an instance of ServiceExisting.    // But because it has been replaced with its mock copy    // we should see an empty name.    expect(tokens[1]).toEqual(jasmine.any(ServiceExisting));    expect(tokens[1].name).toBeUndefined();
    // Checking that we have here what factory has been created.    expect(tokens[2]).toEqual('FACTORY');
    // Checking the set value.    expect(tokens[3]).toEqual('VALUE');  });});