Parse a filemodify command within a commit.

        :param info: a string in the format "mode dataref path"
          (where dataref might be the hard-coded literal 'inline').

def _parse_file_modify(self, info):
        """Parse a filemodify command within a commit.

        :param info: a string in the format "mode dataref path"
          (where dataref might be the hard-coded literal 'inline').
        """
        params = info.split(b' ', 2)
        path = self._path(params[2])
        mode = self._mode(params[0])
        if params[1] == b'inline':
            dataref = None
            data = self._get_data(b'filemodify')
        else:
            dataref = params[1]
            data = None
        return commands.FileModifyCommand(path, mode, dataref,
            data)