anchor.diff:    });
   
     test('fastReassemble behavior triggers hot reload behavior with evaluation of expression', () async {
  -    final StringBuffer stdout = StringBuffer();
  -    final StreamSubscription<String> subscription = flutter.stdout.listen(stdout.writeln);
  +    final Completer<void> tick1 = Completer<void>();
  +    final Completer<void> tick2 = Completer<void>();
  +    final Completer<void> tick3 = Completer<void>();
  +    final StreamSubscription<String> subscription = flutter.stdout.listen((String line) {
  +      if (line.contains('TICK 1')) {
  +        tick1.complete();
  +      }
  +      if (line.contains('TICK 2')) {
  +        tick2.complete();
  +      }
  +      if (line.contains('TICK 3')) {
  +        tick3.complete();
  +      }
  +    });
       await flutter.run(withDebugger: true);
   
       final int port = flutter.vmServicePort;
       final VmService vmService = await vmServiceConnectUri('ws://localhost:$port/ws');
  +    await tick1.future;
       try {
         // Since the single-widget reload feature is not yet implemented, manually
         // evaluate the expression for the reload.
  
positive.code: 
        // _extensionType indicates success.
        expect(fastReassemble2.type, '_extensionType');
        expect(stdout.toString(), isNot(contains('(((TICK 3))))')));
  
        // Invocation without evaluation leads to runtime error.
        expect(vmService
  
negative.code: 
        // _extensionType indicates success.
        expect(fastReassemble1.type, '_extensionType');
        await tick2.future;
  
        // verify evaluation did not produce invalidat type by checking with dart:core
        // type.
  