anchor.diff:  import 'package:gltf/src/utils.dart';
   import 'package:isolate/load_balancer.dart';
   import 'package:isolate/isolate_runner.dart';
  -import 'package:path/path.dart' as path;
  +import 'package:path/path.dart' as p;
   import 'package:yaml/yaml.dart';
   
   const int kErrorCode = 1;
  
positive.code:   final reader = GltfReader.filename(file.openRead(), task.filename, context);
  
    if (reader == null) {
      final ext = path.extension(task.filename).toLowerCase();
      errPipe.write('Error while loading ${file.path}...\n'
          'Unknown file extension `$ext`.\n');
      watch.stop();
  
negative.code: 
      final it = Directory(input).listSync(recursive: true).where((entry) {
        if (entry is File) {
          final ext = p.extension(entry.path);
          return (ext == '.gltf') || (ext == '.glb');
        }
        return false;
  