anchor.diff:  class Baz {}
   ''');
         renderersLibrary = await resolveGeneratedLibrary(writer);
  -      var rendererAsset = AssetId.parse('foo|lib/foo.renderers.dart');
  +      var rendererAsset = AssetId('foo', 'lib/foo.renderers.dart');
         generatedContent = utf8.decode(writer.assets[rendererAsset]);
       });
   
  
positive.code: library foo;
  import 'package:mustachio/annotations.dart';
  ''');
        var rendererAsset = AssetId.parse('foo|lib/foo.renderers.dart');
        generatedContent = utf8.decode(writer.assets[rendererAsset]);
      });
  
  
negative.code: 
    Future<LibraryElement> resolveGeneratedLibrary(
        InMemoryAssetWriter writer) async {
      var rendererAsset = AssetId('foo', 'lib/foo.renderers.dart');
      var writtenStrings = writer.assets
          .map((id, content) => MapEntry(id.toString(), utf8.decode(content)));
      return await resolveSources(writtenStrings,
  