public static <T> ParseFiles<T> parseFilesGenericRecords(
      SerializableFunction<GenericRecord, T> parseFn) {
    return new AutoValue_ParquetIO_ParseFiles.Builder<T>().setParseFn(parseFn).build();
  }
@Test
  @SuppressWarnings({"nullable", "ConstantConditions"} /* forced check. */)
  public void testReadFilesUnknownSchemaFilesForGenericRecordThrowException() {
    IllegalArgumentException illegalArgumentException =
        assertThrows(
            IllegalArgumentException.class,
            () ->
                ParquetIO.parseFilesGenericRecords(GenericRecordPassthroughFn.create())
                    .expand(null));

    assertEquals(
        "Parse can't be used for reading as GenericRecord.", illegalArgumentException.getMessage());
  }