List write()

in frontend_server_common/lib/src/asset_server.dart [151:223]
67 lines of code
9 McCabe index (conditional complexity)

  List<String> write(
      File codeFile, File manifestFile, File sourcemapFile, File metadataFile) {
    var modules = <String>[];
    var codeBytes = codeFile.readAsBytesSync();
    var sourcemapBytes = sourcemapFile.readAsBytesSync();
    var metadataBytes = metadataFile.readAsBytesSync();
    var manifest =
        castStringKeyedMap(json.decode(manifestFile.readAsStringSync()));
    for (var filePath in manifest.keys) {
      if (filePath == null) {
        _logger.severe('Invalid manfiest file: $filePath');
        continue;
      }
      var offsets = castStringKeyedMap(manifest[filePath]);
      var codeOffsets = (offsets['code'] as List<dynamic>).cast<int>();
      var sourcemapOffsets =
          (offsets['sourcemap'] as List<dynamic>).cast<int>();
      var metadataOffsets = (offsets['metadata'] as List<dynamic>).cast<int>();
      if (codeOffsets.length != 2 ||
          sourcemapOffsets.length != 2 ||
          metadataOffsets.length != 2) {
        _logger.severe('Invalid manifest byte offsets: $offsets');
        continue;
      }

      var codeStart = codeOffsets[0];
      var codeEnd = codeOffsets[1];
      if (codeStart < 0 || codeEnd > codeBytes.lengthInBytes) {
        _logger.severe('Invalid byte index: [$codeStart, $codeEnd]');
        continue;
      }
      var byteView = Uint8List.view(
        codeBytes.buffer,
        codeStart,
        codeEnd - codeStart,
      );
      _files[filePath] = byteView;

      var sourcemapStart = sourcemapOffsets[0];
      var sourcemapEnd = sourcemapOffsets[1];
      if (sourcemapStart < 0 || sourcemapEnd > sourcemapBytes.lengthInBytes) {
        _logger.severe('Invalid byte index: [$sourcemapStart, $sourcemapEnd]');
        continue;
      }
      var sourcemapView = Uint8List.view(
        sourcemapBytes.buffer,
        sourcemapStart,
        sourcemapEnd - sourcemapStart,
      );
      _sourcemaps['$filePath.map'] = sourcemapView;

      var metadataStart = metadataOffsets[0];
      var metadataEnd = metadataOffsets[1];
      if (metadataStart < 0 || metadataEnd > metadataBytes.lengthInBytes) {
        _logger.severe('Invalid byte index: [$metadataStart, $metadataEnd]');
        continue;
      }
      var metadataView = Uint8List.view(
        metadataBytes.buffer,
        metadataStart,
        metadataEnd - metadataStart,
      );
      _metadata['$filePath.metadata'] = metadataView;

      modules.add(filePath);
    }

    _mergedMetadata = _metadata.values
        .map((Uint8List encoded) => utf8.decode(encoded))
        .join('\n');

    return modules;
  }