[PATCH/RFC v1 1/1] test-lint: sed -E (or -a, -l) are not portable

From: Torsten Bögershausen <tboegi@web.de>

From `man sed` (on a Mac OS X box): The -E, -a and -i options are non-standard FreeBSD extensions and may not be available on other operating systems.

From `man sed` on a Linux box:
REGULAR EXPRESSIONS
       POSIX.2 BREs should be supported, but they aren't completely because of
       performance problems.  The \n sequence in a regular expression matches
       the newline character,  and  similarly  for \a, \t, and other sequences.
       The -E option switches to using extended regular expressions instead;
       the -E option has been supported for years by GNU sed, and is now
       included in POSIX.

Well, there are still a lot of systems out there, which don't support it.

Beside that, see IEEE Std 1003.1TM-2017 http://pubs.opengroup.org/onlinepubs/9699919799/ does not mention -E either.

To be on the safe side, don't allow it.

Reported-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
---

I am somewhat unsure if we should disable all options except -e -f -n instead ? /\bsed\s+-[^efn]/ and err 'Not portable option with sed. Only -n -e -f are portable';

That would cause a false positive in t9001 here: "--cc-cmd=./cccmd-sed --suppress-cc=self"

which could either be fixed by an anchor: /^\s*sed\s+-[^efn]/

Or by allowing '--' like this: /\bsed\s+-[^-efn]/

Any thoughts, please ?

t/check-non-portable-shell.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)