.replace(REGEX_REPLACE_LEADING_EXCAPED_EXCLAMATION, '!')
        // > Put a backslash ("\") in front of the first hash for patterns that
        // >   begin with a hash.
        .replace(REGEX_REPLACE_LEADING_EXCAPED_HASH, '#')

    const regex = makeRegex(pattern, ignoreCase)

    return new IgnoreRule(
        origin,
        pattern,
        negative,
        regex