public final TestSubscriber assertSubscribed(){
  String prefix="";
  if (done.getCount() != 0) {
    prefix="Subscriber still running! ";
  }
  if (subscription.get() == null) {
    fail(prefix,"Not subscribed!",errors);
  }
  return this;
}

public final TestSubscriber assertSubscribed ( ) { String prefix = "" ; if ( done . getCount ( ) != 0 ) { prefix = "Subscriber still running! " ; } if ( subscription . get ( ) == null ) { fail ( prefix , "Not subscribed!" , errors ) ; } return this ; }
assert that the onsubscribe method was called exactly once .
