import { EventEmitter } from '@angular/core' ; import { Observable , of as observableOf } from 'rxjs' ; export class MockTranslateService { onLangChange : EventEmitter < any > = new EventEmitter ( ) ; onTranslationChange : EventEmitter < any > = new EventEmitter ( ) ; onDefaultLangChange : EventEmitter < any > = new EventEmitter ( ) ; setDefaultLang ( lang ) { return ; } use ( lang ) { return observableOf ( lang ) ; } addLangs ( langs ) { return ; } get ( key , interpolateParams ? ) { return observableOf ( key ) ; } }