# Copyright (c) 2018 - 2020  Peter Pentchev <roam@ringlet.net>
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"""Utility functions for the confget test cases."""

import re


_RE_APOS = re.compile("(?P<pre> [^']* ) (?P<apos> '+ ) (?P<post> .* )", re.X)


def shell_escape(value):
    # type: (str) -> str
    """Escape a value for the shell."""
    res = "'"
    while True:
        match = _RE_APOS.match(value)
        if not match:
            return res + value + "'"

        res += match.group("pre") + "'\"" + match.group("apos") + "\"'"
        value = match.group("post")
