anchor.diff:          defaultsTo: 'out/ios_sim_Release/');
     }
   
  -  String get usageFooter =>
  -    'Run "flutter -h -v" for verbose help output, including less commonly used options.\n'
  -    '\n'
  -    '${doctor.summaryText}';
  +  String get usageFooter {
  +    return 'Run "flutter -h -v" for verbose help output, including less commonly used options.\n'
  +           '\n'
  +           '${doctor.summaryText}';
  +  }
   
     List<BuildConfiguration> get buildConfigurations {
       if (_buildConfigurations == null)
  
positive.code:   List<BuildConfiguration> _buildConfigurations;
  
    String get enginePath {
      if (!_enginePathSet) {
        _enginePath = _findEnginePath(_globalResults);
        _enginePathSet = true;
      }
      return _enginePath;
    }
    String _enginePath;
    bool _enginePathSet = false;
  
    ArgResults _globalResults;
  
    String get _defaultFlutterRoot {
      if (Platform.environment.containsKey(kFlutterRootEnvironmentVariableName))
        return Platform.environment[kFlutterRootEnvironmentVariableName];
  
      try {
        String script = Platform.script.toFilePath();
        if (path.basename(script) == kSnapshotFileName)
  
negative.code: 
      if (androidSdk != null) {
        printTrace('Using Android SDK at ${androidSdk.directory}.');
        if (androidSdk.latestVersion != null)
          printTrace('${androidSdk.latestVersion}');
      }
  
      if (globalResults['version']) {
        printStatus(getVersion(ArtifactStore.flutterRoot));
  