more tests

src/main/webapp/app/admin/review-management/review-management.service.spec.ts

+import { HttpClientModule } from '@angular/common/http';
+import { HttpClientTestingModule, HttpTestingController } from '@angular/common/http/testing';
+import { ComponentFixture, getTestBed, TestBed } from '@angular/core/testing';
+import { RouterTestingModule } from '@angular/router/testing';
+import { TranslateModule } from '@ngx-translate/core';
+import { ApplicationConfigService } from 'app/core/config/application-config.service';
+import { LocalStorageService, SessionStorageService } from 'ngx-webstorage';
+import { MultiSelectDropdownExerciseComponent } from './multi-select-dropdown-exercise/multi-select-dropdown-exercise.component';
+import { ReviewManagementService } from './review-management.service';
+import { ReviewStatisticsDTO } from './review.model';
+
+describe('ReviewManagementService', () => {
+  let injector: TestBed;
+  let service: ReviewManagementService;
+  let fixture: ComponentFixture<ReviewManagementService>;
+  let httpMock: HttpTestingController;
+  let applicationConfigService: ApplicationConfigService;
+
+  beforeEach(async () => {
+    TestBed.configureTestingModule({
+      imports: [HttpClientTestingModule, HttpClientModule, TranslateModule.forRoot(), RouterTestingModule],
+      declarations: [],
+      providers: [ApplicationConfigService, LocalStorageService, SessionStorageService, MultiSelectDropdownExerciseComponent],
+    });
+
+    injector = getTestBed();
+    applicationConfigService = TestBed.inject(ApplicationConfigService);
+    service = TestBed.inject(ReviewManagementService);
+    httpMock = TestBed.inject(HttpTestingController);
+  });
+
+  it('should inject', () => {
+    expect(service).toBeTruthy();
+  });
+
+  it('test Caching', () => {
+    let isInvoked = 0;
+    service.getReviewStatistics().subscribe(data => {
+      console.log('data: ' + data);
+      isInvoked++;
+    });
+    expect(isInvoked).toEqual(1); // it is invoked with undefined
+    const testRequest = httpMock.expectOne({
+      method: 'POST',
+      url: applicationConfigService.getEndpointFor('api/review/countAllByUser'),
+    });
+    testRequest.flush({
+      reviewInProgress: 0,
+      reviewImproved: 0,
+      reviewCompleted: 0,
+      unknownStats: 0,
+      reviewsRequestedByUser: 2,
+      reviewInProgressByUser: 0,
+      reviewImprovementRequestedByUser: 2,
+      reviewCompletedByUser: 0,
+      unknownStatsByUser: 0,
+      badgesRewarded: 1,
+    });
+    expect(isInvoked).toEqual(2);
+
+    service.getReviewStatistics().subscribe(data => {
+      isInvoked++;
+    });
+    expect(isInvoked).toEqual(3); // result is returned immediately from cache
+    httpMock.expectNone({});
+  });
+});

src/main/webapp/app/admin/review-management/review-management.service.ts

-import { EventEmitter, Injectable } from '@angular/core';
+import { Injectable } from '@angular/core';
 import { HttpClient } from '@angular/common/http';
 import { BehaviorSubject, Observable, tap } from 'rxjs';
 import { ApplicationConfigService } from 'app/core/config/application-config.service';