anchor.diff:      FakeDeviceLogReader logReader;
       ProtocolDiscovery discoverer;
   
  -    /// Performs test set-up functionality that must be performed as part of
  -    /// the `test()` pass and not part of the `setUp()` pass.
  -    ///
  -    /// This exists to make sure we're not creating an error that tries to
  -    /// cross an error-zone boundary. Our use of `testUsingContext()` runs the
  -    /// test code inside an error zone, but the `setUp()` code is not run in
  -    /// any zone. This creates the potential for errors that try to cross
  -    /// error-zone boundaries, which are considered uncaught.
  -    ///
  -    /// This also exists for cases where our initialization requires access to
  -    /// a `Context` object, which is only set up inside the zone.
  -    ///
  -    /// These issues do not pertain to real code and are a test-only concern,
  -    /// because in real code, the zone is set up in `main()`.
  -    ///
  -    /// See also: [runZoned]
  -    void initialize({
  -      int devicePort,
  -      Duration throttleDuration = const Duration(milliseconds: 200),
  -    }) {
  +    setUp(() {
         logReader = FakeDeviceLogReader();
         discoverer = ProtocolDiscovery.observatory(
           logReader,
           ipv6: false,
           hostPort: null,
  -        devicePort: devicePort,
  -        throttleDuration: throttleDuration,
  +        devicePort: null,
  +        throttleDuration: const Duration(milliseconds: 200),
           logger: BufferLogger.test(),
         );
  -    }
  -
  -    testUsingContext('returns non-null uri future', () async {
  -      initialize();
  +    });
  +
  +    testWithoutContext('returns non-null uri future', () async {
         expect(discoverer.uri, isNotNull);
       });
   
  
positive.code:         expect('$uri', 'http://127.0.0.1:9999');
        });
  
        testUsingContext('uri throws if logs produce bad line and no listener is attached', () async {
          initialize();
          logReader.addLine('Observatory listening on http://127.0.0.1:apple');
  
          await Future<void>.delayed(Duration.zero);
  
negative.code:         });
        });
  
        testWithoutContext('uris in the stream are throttled when they match the port', () async {
          const Duration kThrottleTimeInMilliseconds = Duration(milliseconds: 10);
  
          FakeAsync().run((FakeAsync time) {
            discoverer = ProtocolDiscovery.observatory(
              logReader,
              ipv6: false,
              hostPort: null,
              devicePort: 12345,
              throttleDuration: kThrottleTimeInMilliseconds,
              logger: BufferLogger.test(),
            );
  
            final List<Uri> discoveredUris = <Uri>[];
  