anchor.diff:  class StreamHttpRequestMock extends Mock implements Stream<HttpRequest> {}
   
   void main() {
  -  group('(Backend)', () {
  +  group('(Backend mock)', () {
       Backend backend;
       MockHttpServer server;
       MockRequestNavigator requestNavigator;
  
positive.code:       // then
        requestNavigator.getLogs(callsTo('registerDefaultHandler')).verify(happenedOnce);
      });
  
      test('addNotFoundView with forgotten backslash - not matched route', () {
        //setUp real-like environment - so the backend made redirect callback will be called
        var realRouter = new Router("", {});
        var realRequestNavigator = new RequestNavigator(
            new StreamHttpRequestMock(), realRouter);
  
        backend = new Backend.config(server, realRouter, realRequestNavigator,
            hmac, httpBodyHandler.processRequest);
  
        // given
        backend.addRoute('static', new Route('/static/'));
        backend.addView('static', (_) {});
  
negative.code:     });
  
      test('addNotFoundView with forgotten backslash - matched route', () {
        // given
        backend.addRoute('directory', new Route('/static/*'));
        backend.addView('directory', expectAsync1((_) {}, count : 1));
        backend.addNotFoundView(expectAsync1((_) {}, count : 0));
  
        //incoming request
  