From: Jeff King <peff@peff.net>
To: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
Cc: "Git Mailing List" <git@vger.kernel.org>,
"Junio C Hamano" <gitster@pobox.com>,
"Jeffrey Walton" <noloader@gmail.com>,
"Michał Kiedrowicz" <michal.kiedrowicz@gmail.com>,
"J Smith" <dark.panda@gmail.com>,
"Victor Leschuk" <vleschuk@gmail.com>,
"Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>
Subject: Re: [PATCH 05/12] log: add exhaustive tests for pattern style options & config
Date: Tue, 11 Apr 2017 06:51:31 -0400 [thread overview]
Message-ID: <20170411105130.2ezvvm4kl5wdav3x@sigill.intra.peff.net> (raw)
In-Reply-To: <CACBZZX5jGGUToK83e2iugpbSBDpATi7J0BWg9=UY=YC4ZixT+Q@mail.gmail.com>
On Tue, Apr 11, 2017 at 12:32:57PM +0200, Ævar Arnfjörð Bjarmason wrote:
> > This can be tricky since POSIX allows implementations to add arbitrary
> > extensions for otherwise invalid syntax.
>
> For POSIX basic v.s. extended I'm relying on (|) not being
> metacharacters in basic but metachars needing quoting in extended. I
> very much doubt any regex implementation doesn't conform to that, but
> maybe some crazy implementation does...
Yeah, I think BRE vs ERE (vs fixed) is fine, because POSIX specifies the
differences. It's really PCRE, because ERE implementations have a
surprising amount of flexibility according to the standard (basically
anything invalid is listed as "undefined" and implementations are
allowed to do what they please).
> >> + if test_have_prereq LIBPCRE
> >> + then
> >> + git -c grep.patternType=perl log --pretty=tformat:%s \
> >> + --grep="\((?=1)" >actual.perl
> >> + fi &&
> >
> > I'd have to double-check POSIX, but I suspect that it may allow (?=1) to
> > work in an ERE (since it's otherwise bogus to have "?" without a prior
> > element to match).
>
> Distinguishing PCRE from the rest is much easier, I'll add some more
> obscure PCRE feature to that which definitely doesn't exist in any
> POSIX rx library, e.g. (*COMMIT) or something.
I think (*) would be "undefined" by POSIX, and thus allowed for
extensions (though in practice it's probably fine). The "[\d]" trick was
the simplest one I could find that is reliably defined to be different
between ERE and PCRE.
-Peff
next prev parent reply other threads:[~2017-04-11 10:53 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-08 13:24 [PATCH 00/12] PCREv2 & more Ævar Arnfjörð Bjarmason
2017-04-08 13:24 ` [PATCH 01/12] grep: add ability to disable threading with --threads=0 or grep.threads=0 Ævar Arnfjörð Bjarmason
2017-04-11 10:06 ` Jeff King
2017-04-11 20:20 ` Ævar Arnfjörð Bjarmason
2017-04-11 20:34 ` Jeff King
2017-04-11 20:56 ` Ævar Arnfjörð Bjarmason
2017-04-14 21:23 ` Jeff King
2017-04-16 22:25 ` Ævar Arnfjörð Bjarmason
2017-04-08 13:24 ` [PATCH 02/12] grep: remove redundant regflags assignment under PCRE Ævar Arnfjörð Bjarmason
2017-04-11 10:10 ` Jeff King
2017-04-08 13:24 ` [PATCH 03/12] Makefile & configure: reword outdated comment about PCRE Ævar Arnfjörð Bjarmason
2017-04-11 10:14 ` Jeff King
2017-04-15 12:10 ` Ævar Arnfjörð Bjarmason
2017-04-08 13:24 ` [PATCH 04/12] grep: add a test for backreferences in PCRE patterns Ævar Arnfjörð Bjarmason
2017-04-08 13:24 ` [PATCH 05/12] log: add exhaustive tests for pattern style options & config Ævar Arnfjörð Bjarmason
2017-04-11 10:23 ` Jeff King
2017-04-11 10:32 ` Ævar Arnfjörð Bjarmason
2017-04-11 10:51 ` Jeff King [this message]
2017-04-08 13:25 ` [PATCH 06/12] log: add -P as a synonym for --perl-regexp Ævar Arnfjörð Bjarmason
2017-04-10 2:39 ` Junio C Hamano
2017-04-11 10:26 ` Jeff King
2017-04-08 13:25 ` [PATCH 07/12] grep & rev-list doc: stop promising libpcre " Ævar Arnfjörð Bjarmason
2017-04-08 13:25 ` [PATCH 08/12] grep: make grep.patternType=[pcre|pcre1] a synonym for "perl" Ævar Arnfjörð Bjarmason
2017-04-11 10:30 ` Jeff King
2017-04-08 13:25 ` [PATCH 09/12] test-lib: rename the LIBPCRE prerequisite to PCRE Ævar Arnfjörð Bjarmason
2017-04-11 10:31 ` Jeff King
2017-04-08 13:25 ` [PATCH 10/12] grep: change the internal PCRE macro names to be PCRE1 Ævar Arnfjörð Bjarmason
2017-04-11 10:35 ` Jeff King
2017-04-11 10:51 ` Ævar Arnfjörð Bjarmason
2017-04-11 10:53 ` Jeff King
2017-04-08 13:25 ` [PATCH 11/12] grep: change the internal PCRE code & header " Ævar Arnfjörð Bjarmason
2017-04-11 10:37 ` Jeff King
2017-04-11 10:45 ` Ævar Arnfjörð Bjarmason
2017-04-11 10:48 ` Jeff King
2017-04-11 11:02 ` Ævar Arnfjörð Bjarmason
2017-04-11 12:57 ` Jeff King
2017-04-11 16:51 ` Brandon Williams
2017-04-11 18:31 ` Ævar Arnfjörð Bjarmason
2017-04-08 13:25 ` [PATCH 12/12] grep: add support for PCRE v2 Ævar Arnfjörð Bjarmason
2017-04-11 10:43 ` Jeff King
2017-04-11 10:47 ` [PATCH 00/12] PCREv2 & more Jeff King
2017-04-15 8:11 ` Junio C Hamano
2017-04-15 9:50 ` Ævar Arnfjörð Bjarmason
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: http://vger.kernel.org/majordomo-info.html
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20170411105130.2ezvvm4kl5wdav3x@sigill.intra.peff.net \
--to=peff@peff.net \
--cc=avarab@gmail.com \
--cc=dark.panda@gmail.com \
--cc=git@vger.kernel.org \
--cc=gitster@pobox.com \
--cc=michal.kiedrowicz@gmail.com \
--cc=noloader@gmail.com \
--cc=pclouds@gmail.com \
--cc=vleschuk@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://80x24.org/mirrors/git.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).