parameterValues method

List<Object> parameterValues(List<TypeIdentifier> paramTypes)

Decode parameter values per §II.23.3 of ECMA-335.

Implementation

List<Object> parameterValues(List<TypeIdentifier> paramTypes) {
  final paramValues = <Object>[];
  final blob = signatureBlob.buffer.asByteData();
  var offset = 2; // skip two-byte 0x0001 prolog
  for (var paramIdx = 0; paramIdx < paramTypes.length; paramIdx++) {
    var baseType = paramTypes[paramIdx].baseType;
    if (paramTypes[paramIdx].type?.isEnum == true) {
      // find the type of the .value property (likely an Int32 or
      // Uint32) and use that instead...
      baseType =
          paramTypes[paramIdx].type!.fields.first.typeIdentifier.baseType;
    }
    switch (baseType) {
      case BaseType.String:
      case BaseType.ClassTypeModifier: // canonical name represented in value
        // Get string length and move pointer forward
        final packedLen =
            UncompressedData.fromBlob(blob.buffer.asUint8List(offset, 4));
        final stringLength = packedLen.data;
        offset += packedLen.dataLength;

        // Add decoded string value and move pointer forward
        paramValues.add(const Utf8Decoder()
            .convert(blob.buffer.asUint8List(offset, stringLength)));
        offset += stringLength;
        break;
      case BaseType.Boolean:
        paramValues.add(blob.getUint8(offset) == 1);
        offset += 1;
        break;
      case BaseType.Char:
        paramValues.add(String.fromCharCode(blob.getUint16(offset)));
        offset += 2;
        break;
      case BaseType.Float:
        paramValues.add(blob.getFloat32(offset, Endian.little));
        offset += 4;
        break;
      case BaseType.Double:
        paramValues.add(blob.getFloat64(offset, Endian.little));
        offset += 8;
        break;
      case BaseType.Int8:
        paramValues.add(blob.getInt8(offset));
        offset += 1;
        break;
      case BaseType.Int16:
        paramValues.add(blob.getInt16(offset, Endian.little));
        offset += 2;
        break;
      case BaseType.Int32:
        paramValues.add(blob.getInt32(offset, Endian.little));
        offset += 4;
        break;
      case BaseType.Int64:
        paramValues.add(blob.getInt64(offset, Endian.little));
        offset += 8;
        break;
      case BaseType.Uint8:
        paramValues.add(blob.getUint8(offset));
        offset += 1;
        break;
      case BaseType.Uint16:
        paramValues.add(blob.getUint16(offset, Endian.little));
        offset += 2;
        break;
      case BaseType.Uint32:
        paramValues.add(blob.getUint32(offset, Endian.little));
        offset += 4;
        break;
      case BaseType.Uint64:
        paramValues.add(blob.getUint64(offset, Endian.little));
        offset += 8;
        break;
      default:
        // TODO: Need more exhaustive checking here for more esoteric
        // parameter types that are specified in ECMA-335 but don't seem to
        // occur in the Win32 or WinRT metadata (e.g. named arguments).
        throw WinmdException('Unexpected parameter type in signature blob.');
    }
  }

  return paramValues;
}