Return list of error dicts for all found errors in paths.

        The default implementation expects `tool`, and `tool_err_re` to be
        defined.

        tool: external binary to use for checking.
        tool_err_re: regexp that can match output of `tool` -- must provide
            a groupdict with at least "filename", "lineno", "colno",
            and "msg" keys. See example checkers.

def check(self, paths):
        """
        Return list of error dicts for all found errors in paths.

        The default implementation expects `tool`, and `tool_err_re` to be
        defined.

        tool: external binary to use for checking.
        tool_err_re: regexp that can match output of `tool` -- must provide
            a groupdict with at least "filename", "lineno", "colno",
            and "msg" keys. See example checkers.
        """
        if not paths:
            return ()

        cmd_pieces = [self.tool]
        cmd_pieces.extend(self.tool_args)
        return self._check_std(paths, cmd_pieces)