anchor.diff:      if (!sessionFilePath.endsWith('.json')) {
         throw 'expected *.json but found $sessionFilePath';
       }
  -    var index = sessionFilePath.indexOf('-', sessionFilePath.lastIndexOf('/'));
  -    var name = sessionFilePath.substring(index + 1, sessionFilePath.length - 5);
  -    Map sessionInfo;
  -    if (name.startsWith('PRI')) {
  -      // Provide simplified session info for a PRI file
  -      return {SESSION_ID: name.substring(3)};
  -    } else {
  -      // Read the session info from the associated PRI file
  -      var priPath = '${sessionFilePath.substring(0, index)}-PRI$name.json';
  -      Stream<List<int>> stream = new io.File(priPath).openRead();
  -      sessionInfo = await readSessionInfo(name, stream);
  -    }
  +    // var index = sessionFilePath.indexOf('-', sessionFilePath.lastIndexOf('/'));
  +    // var name = sessionFilePath.substring(index + 1, sessionFilePath.length - 5);
  +    // Map sessionInfo;
  +    // if (name.startsWith('PRI')) {
  +    //   // Provide simplified session info for a PRI file
  +    //   return {SESSION_ID: name.substring(3)};
  +    // } else {
  +    //   // Read the session info from the associated PRI file
  +    //   var priPath = '${sessionFilePath.substring(0, index)}-PRI$name.json';
  +    //   Stream<List<int>> stream = new io.File(priPath).openRead();
  +    //   sessionInfo = await readSessionInfo(name, stream);
  +    // }
       this.addResult = (String key, dynamic value) {
         var json;
         try {
  
positive.code:   if (io.FileSystemEntity.isDirectorySync(path)) {
      files = new io.Directory(path).listSync().where((file) {
        var name = basename(file.path);
        return name.startsWith('compressed-') && name.endsWith('.json');
      }).toList();
    } else {
      files = [new io.File(path)];
  
negative.code:       var stopwatch = new Stopwatch()..start();
  
        // Initialize query specific objects
        TestMapper mapper = new TestMapper(new SevereLogMapper(), file.path);
  
        // Extraction
        await mapper.init({}, (String key, value) {
  