parse-options: simplify positivation handling
We accept the positive version of options whose long name starts with "no-" and are defined without the flag PARSE_OPT_NONEG. E.g. git clone has an explicitly defined --no-checkout option and also implicitly accepts --checkout to override it. parse_long_opt() handles that by restarting the option matching with the positive version when it finds that only the current option definition starts with "no-", but not the user-supplied argument. This code is located almost at the end of the matching logic. Avoid the need for a restart by moving the code up. We don't have to check the positive arg against the negative long_name at all -- the "no-" prefix of the latter makes a match impossible. Skip it and toggle OPT_UNSET right away to simplify the control flow. Signed-off-by: René Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>