docs: def writeInfoLine(self, stream, fromUUID, size):
          """ Write one line of diff information. """
          if size is None or fromUUID is None:
              return
          if not isinstance(size, int):
              logger.warning("Bad size: %s", size)
              return
          stream.write(str("%s\t%s\t%d\n" % (
              self.uuid,
              fromUUID,
              size,
          )))