anchor.diff:      test('callMulticastService throws exception', () async {
         await env.setupEnvironment();
   
  -      expect(serviceManager.callService('fakeMethod'), throwsException);
  +      await expectLater(
  +          serviceManager.callService('fakeMethod'), throwsException);
   
         await env.tearDownEnvironment();
       });
  
positive.code: import 'support/flutter_test_driver.dart';
  import 'support/flutter_test_environment.dart';
  
  void main() {
    group('serviceManagerTests', () {
      final FlutterTestEnvironment env = FlutterTestEnvironment(
  
negative.code: 
      test('invalid setBreakpoint throws exception', () async {
        await env.setupEnvironment();
  
        await expectLater(
          serviceManager.service.addBreakpoint(
              serviceManager.isolateManager.selectedIsolate.id,
              'fake-script-id',
              1),
          throwsA(const TypeMatcher<RPCError>()
              .having((e) => e.code, 'code', equals(jsonRpcInvalidParamsCode))),
        );
  
        await env.tearDownEnvironment();
      });
  
      test('toggle boolean service extension', () async {
  