On 14-Jan-23 10:31, René Scharfe wrote:
Am 14.01.23 um 07:44 schrieb René Scharfe:
Am 13.01.23 um 18:19 schrieb Junio C Hamano:
Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> writes:
On Thu, Jan 12 2023, Jeff King wrote:
There's a couple of ways out of this that I don't see in this thread:
- Declare it not a problem: We have -G, -E and -P to map to BRE, ERE and
PCRE. One view is to say the first two must match POSIX, another is
tha whatever the platform thinks they should do is how they should
act.
... this view. The story "BRE and ERE work via what system
libraries provide, and 'git grep' matches what system grep' does" is
an easy to understand view.
That was my stance in my first reply as well. But 3632cfc248 (Use
compatibility regex library for OSX/Darwin, 2008-09-07) explicitly
added alternation support for BREs on macOS, and 1819ad327b (grep: fix
multibyte regex handling under macOS, 2022-08-26) removed it seemingly
by accident. And grep(1) does support them on macOS 13.1:
Indeed, I removed the alternation handling functionality by accident. I
was not aware of the BRE-handling difference between the GNU and the
macOS native regex library. I think having git-grep behave the same as
grep(1) on each platform is consistent with the principle of least
astonishment (POLA). This would mean that on macOS plain git-grep
should use enhanced basic REs as proposed in René's patch.
Diomidis
