it('should delay the source if values are not emitted often enough', () => {
    const e1 =   hot('-a--------b-----c----|');
    const subs =     '^                    !';
    const expected = '------a--------b-----|';

    expectObservable(e1.pipe(auditTime(50, rxTestScheduler))).toBe(expected);
    expectSubscriptions(e1.subscriptions).toBe(subs);
  });

  asDiagram('auditTime(50)')('should emit the last value in each time window', () => {
    const e1 =   hot('-a-x-y----b---x-cx---|');
    const subs =     '^                    !';
    const expected = '------y--------x-----|';

    const result = e1.pipe(auditTime(50, rxTestScheduler));

    expectObservable(result).toBe(expected);
    expectSubscriptions(e1.subscriptions).toBe(subs);
  });

    /**
     * Master-component of all apps.
     *
     * Inits the translation service, the operator, the login data and the constants.
     *
     * Handles the altering of Array.toString()
     *
     * @param translate To set the default language
     * @param operator To call the constructor of the OperatorService
     * @param loginDataService to call the constructor of the LoginDataService
     * @param constantService to call the constructor of the ConstantService
     * @param servertimeService executes the scheduler early on
     * @param themeService used to listen to theme-changes
     * @param countUsersService to call the constructor of the CountUserService
     * @param configService to call the constructor of the ConfigService
     * @param loadFontService to call the constructor of the LoadFontService
     * @param dataStoreUpgradeService
     * @param update Service Worker Updates
     */
    public constructor(
        translate: TranslateService,
        appRef: ApplicationRef,
        servertimeService: ServertimeService,
        router: Router,
        operator: OperatorService,
        loginDataService: LoginDataService,
        constantsService: ConstantsService, // Needs to be started, so it can register itself to the WebsocketService
        themeService: ThemeService,
        spinnerService: SpinnerService,
        countUsersService: CountUsersService, // Needed to register itself.
        configService: ConfigService,
        loadFontService: LoadFontService,
        dataStoreUpgradeService: DataStoreUpgradeService, // to start it.
        update: UpdateService,
        prioritizeService: PrioritizeService,
        pingService: PingService
    ) {
        // manually add the supported languages
        translate.addLangs(['en', 'de', 'cs']);
        // this language will be used as a fallback when a translation isn't found in the current language
        translate.setDefaultLang('en');
        // get the browsers default language
        const browserLang = translate.getBrowserLang();
        // try to use the browser language if it is available. If not, uses english.
        translate.use(translate.getLangs().includes(browserLang) ? browserLang : 'en');
        // change default JS functions
        this.overloadArrayToString();
        // Show the spinner initial
        spinnerService.setVisibility(true, translate.instant('Loading data. Please wait...'));

        appRef.isStable
            .pipe(
                // take only the stable state
                filter(s => s),
                take(1)
            )
            .subscribe(() => servertimeService.startScheduler());

        // Subscribe to hide the spinner if the application has changed.
        appRef.isStable
            .pipe(
                filter(s => s),
                auditTime(1000)
            )
            .pipe(take(2))
            .subscribe(() => {
                spinnerService.setVisibility(false);
            });
    }