[PATCH/RFC v2 1/1] test-lint: Only use only sed [-n] [-e command] [-f command_file]

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

To be on the safe side, don't allow -E (or -r, which is GNU). Change check-non-portable-shell.pl to only accept the portable options: sed [-n] [-e command] [-f command_file]

Reported-by: SZEDER Gábor <szeder.dev@gmail.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
---
 t/check-non-portable-shell.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)