anchor.diff:  
   import 'package:analyzer/src/generated/engine.dart' show TimestampedData;
   import 'package:analyzer/src/generated/source.dart';
  +import 'package:path/path.dart' as pkg_path;
   
   /// An implementation of [Source] that's based on an in-memory Dart string.
   class StringSource extends Source {
  
positive.code: 
    StringSource(this._contents, String? fullName, {Uri? uri})
        : fullName = fullName ?? '/test.dart',
          uri = uri ?? Uri.file(fullName ?? 'file:///test.dart'),
          modificationStamp = DateTime.now().millisecondsSinceEpoch;
  
    @override
  
negative.code: 
    @override
    String toString() => 'StringSource ($fullName)';
  
    static Uri _computeUri(Uri? uri, String? fullName) {
      if (uri != null) {
        return uri;
      }
  
      var isWindows = pkg_path.Style.platform == pkg_path.Style.windows;
      if (isWindows) {
        return pkg_path.toUri(r'C:\test.dart');
      } else {
        return pkg_path.toUri(r'/test.dart');
      }
    }
  }
  