import { expect } from 'chai' ; import { Observable , of , Subscriber } from 'rxjs' ; import { observable as symbolObservable } from 'rxjs/internal/symbol/observable' ; import { asInteropObservable , asInteropSubscriber } from './interop-helper' ; describe ( 'interop helper' , ( ) => { it ( 'should simulate interop observables' , ( ) => { const observable = asInteropObservable ( of ( 42 ) ) ; expect ( observable ) . to . not . be . instanceOf ( Observable ) ; expect ( observable [ symbolObservable ] ) . to . be . a ( 'function' ) ; } ) ; it ( 'should simulate interop subscribers' , ( ) => { const subscriber = asInteropSubscriber ( new Subscriber ( ) ) ; expect ( subscriber ) . to . not . be . instanceOf ( Subscriber ) ; } ) ; } ) ;