anchor.diff:  final _connectButton = find.widgetWithText(ElevatedButton, connectButtonLabel);
   final _disconnectButton = find.widgetWithText(FlatButton, disconnectButtonLabel);
   
  -Future _setup({bool connect = false}) async {
  -  var preferences = Map<String, dynamic>();
  -  if (connect) {
  -    preferences[serverURLKey] = hostURL;
  -  }
  -  SharedPreferences.setMockInitialValues(preferences);
  +Future _setup({Map<String, dynamic> preferences}) async {
  +  SharedPreferences.setMockInitialValues(preferences != null ? preferences : Map());
   
     getIt.allowReassignment = true;
   
     getIt.registerSingleton<Host>(await Host.create());
     getIt.registerSingleton<Client>(MockClient());
     final client = getIt<Client>();
  -  when(client.get(apiVersionEndpoint)).thenAnswer((_) async => Response(compatibleAPIVersion, 200));
  +  when(client.get(goodhostURL + apiVersionEndpoint)).thenAnswer((_) async => Response(compatibleAPIVersion, 200));
  +  when(client.get(incompatibleHostURL + apiVersionEndpoint))
  +      .thenAnswer((_) async => Response(incompatibleAPIVersion, 200));
  +  when(client.get(badHostURL + apiVersionEndpoint)).thenThrow('borked internet');
     getIt.registerSingleton<API>(HttpAPI());
     getIt.registerSingleton<connection.Manager>(connection.Manager());
   }
  
positive.code: 
      await tester.pumpWidget(PolarisApp());
  
      final client = getIt<Client>();
      when(client.get(apiVersionEndpoint)).thenThrow('bad host');
  
      await tester.enterText(_urlInputField, hostURL);
      await tester.tap(_connectButton);
      await tester.pump();
      expect(find.widgetWithText(SnackBar, errorNetwork), findsOneWidget);
  
negative.code:     final client = getIt<Client>();
      when(client.get(apiVersionEndpoint)).thenAnswer((_) async => Response(incompatibleAPIVersion, 200));
  
      await tester.enterText(_urlInputField, incompatibleHostURL);
      await tester.tap(_connectButton);
      await tester.pump();
      expect(find.widgetWithText(SnackBar, errorAPIVersion), findsOneWidget);
  