* [PATCH] grep: correctly identify utf-8 characters with \{b,w} in -P @ 2023-01-08 6:23 Carlo Marcelo Arenas Belón 2023-01-08 6:39 ` Junio C Hamano 2023-01-08 15:52 ` [PATCH v2] " Carlo Marcelo Arenas Belón 0 siblings, 2 replies; 36+ messages in thread From: Carlo Marcelo Arenas Belón @ 2023-01-08 6:23 UTC (permalink / raw) To: git; +Cc: avarab, Carlo Marcelo Arenas Belón When UTF is enabled for a PCRE match, the corresponding flags are added to the pcre2_compile() call, but PCRE2_UCP wasn't included. This prevents extending the meaning of the character classes to include those new valid characters and therefore result in failed matches for expressions that rely on that extention, for ex: $ git grep -P '\bÆvar' Add PCRE2_UCP so that \w will include Æ and therefore \b could correctly match the beginning of that word. Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> --- grep.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/grep.c b/grep.c index 06eed69493..1687f65b64 100644 --- a/grep.c +++ b/grep.c @@ -293,7 +293,7 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt options |= PCRE2_CASELESS; } if (!opt->ignore_locale && is_utf8_locale() && !literal) - options |= (PCRE2_UTF | PCRE2_MATCH_INVALID_UTF); + options |= (PCRE2_UTF | PCRE2_UCP | PCRE2_MATCH_INVALID_UTF); #ifndef GIT_PCRE2_VERSION_10_36_OR_HIGHER /* Work around https://bugs.exim.org/show_bug.cgi?id=2642 fixed in 10.36 */ -- 2.37.1 (Apple Git-137.1) ^ permalink raw reply related [flat|nested] 36+ messages in thread
* Re: [PATCH] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-08 6:23 [PATCH] grep: correctly identify utf-8 characters with \{b,w} in -P Carlo Marcelo Arenas Belón @ 2023-01-08 6:39 ` Junio C Hamano 2023-01-08 15:52 ` [PATCH v2] " Carlo Marcelo Arenas Belón 1 sibling, 0 replies; 36+ messages in thread From: Junio C Hamano @ 2023-01-08 6:39 UTC (permalink / raw) To: Carlo Marcelo Arenas Belón; +Cc: git, avarab Carlo Marcelo Arenas Belón <carenas@gmail.com> writes: > When UTF is enabled for a PCRE match, the corresponding flags are > added to the pcre2_compile() call, but PCRE2_UCP wasn't included. Would the same performance concern as https://discourse.julialang.org/t/regex-pcre2-and-the-pcre2-ucp-ucp-flag/10930 apply to us as well? > if (!opt->ignore_locale && is_utf8_locale() && !literal) > - options |= (PCRE2_UTF | PCRE2_MATCH_INVALID_UTF); > + options |= (PCRE2_UTF | PCRE2_UCP | PCRE2_MATCH_INVALID_UTF); > > #ifndef GIT_PCRE2_VERSION_10_36_OR_HIGHER > /* Work around https://bugs.exim.org/show_bug.cgi?id=2642 fixed in 10.36 */ ^ permalink raw reply [flat|nested] 36+ messages in thread
* [PATCH v2] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-08 6:23 [PATCH] grep: correctly identify utf-8 characters with \{b,w} in -P Carlo Marcelo Arenas Belón 2023-01-08 6:39 ` Junio C Hamano @ 2023-01-08 15:52 ` Carlo Marcelo Arenas Belón 2023-01-09 11:35 ` Ævar Arnfjörð Bjarmason 2023-01-17 10:51 ` [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P Carlo Marcelo Arenas Belón 1 sibling, 2 replies; 36+ messages in thread From: Carlo Marcelo Arenas Belón @ 2023-01-08 15:52 UTC (permalink / raw) To: git; +Cc: avarab, gitster, Carlo Marcelo Arenas Belón When UTF is enabled for a PCRE match, the corresponding flags are added to the pcre2_compile() call, but PCRE2_UCP wasn't included. This prevents extending the meaning of the character classes to include those new valid characters and therefore result in failed matches for expressions that rely on that extention, for ex: $ git grep -P '\bÆvar' Add PCRE2_UCP so that \w will include Æ and therefore \b could correctly match the beginning of that word. This has an impact on performance that has been estimated to be between 20% to 40% and that is shown through the added performance test. Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> --- grep.c | 2 +- t/perf/p7822-grep-perl-character.sh | 42 +++++++++++++++++++++++++++++ 2 files changed, 43 insertions(+), 1 deletion(-) create mode 100755 t/perf/p7822-grep-perl-character.sh diff --git a/grep.c b/grep.c index 06eed69493..1687f65b64 100644 --- a/grep.c +++ b/grep.c @@ -293,7 +293,7 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt options |= PCRE2_CASELESS; } if (!opt->ignore_locale && is_utf8_locale() && !literal) - options |= (PCRE2_UTF | PCRE2_MATCH_INVALID_UTF); + options |= (PCRE2_UTF | PCRE2_UCP | PCRE2_MATCH_INVALID_UTF); #ifndef GIT_PCRE2_VERSION_10_36_OR_HIGHER /* Work around https://bugs.exim.org/show_bug.cgi?id=2642 fixed in 10.36 */ diff --git a/t/perf/p7822-grep-perl-character.sh b/t/perf/p7822-grep-perl-character.sh new file mode 100755 index 0000000000..87009c60df --- /dev/null +++ b/t/perf/p7822-grep-perl-character.sh @@ -0,0 +1,42 @@ +#!/bin/sh + +test_description="git-grep's perl regex + +If GIT_PERF_GREP_THREADS is set to a list of threads (e.g. '1 4 8' +etc.) we will test the patterns under those numbers of threads. +" + +. ./perf-lib.sh + +test_perf_large_repo +test_checkout_worktree + +if test -n "$GIT_PERF_GREP_THREADS" +then + test_set_prereq PERF_GREP_ENGINES_THREADS +fi + +for pattern in \ + '\\bhow' \ + '\\bÆvar' \ + '\\d+ \\bÆvar' \ + '\\bBelón\\b' \ + '\\w{12}\\b' +do + echo '$pattern' >pat + if ! test_have_prereq PERF_GREP_ENGINES_THREADS + then + test_perf "grep -P '$pattern'" --prereq PCRE " + git -P grep -f pat || : + " + else + for threads in $GIT_PERF_GREP_THREADS + do + test_perf "grep -P '$pattern' with $threads threads" --prereq PTHREADS,PCRE " + git -c grep.threads=$threads -P grep -f pat || : + " + done + fi +done + +test_done -- 2.39.0.199.g555ddd67e6 ^ permalink raw reply related [flat|nested] 36+ messages in thread
* Re: [PATCH v2] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-08 15:52 ` [PATCH v2] " Carlo Marcelo Arenas Belón @ 2023-01-09 11:35 ` Ævar Arnfjörð Bjarmason 2023-01-09 18:40 ` bug#60690: [PATCH v2] grep: correctly identify utf-8 characters with \{b, w} " Paul Eggert ` (3 more replies) 2023-01-17 10:51 ` [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P Carlo Marcelo Arenas Belón 1 sibling, 4 replies; 36+ messages in thread From: Ævar Arnfjörð Bjarmason @ 2023-01-09 11:35 UTC (permalink / raw) To: Carlo Marcelo Arenas Belón Cc: git, gitster, bug-grep, demerphq, pcre-dev On Sun, Jan 08 2023, Carlo Marcelo Arenas Belón wrote: > When UTF is enabled for a PCRE match, the corresponding flags are > added to the pcre2_compile() call, but PCRE2_UCP wasn't included. > > This prevents extending the meaning of the character classes to > include those new valid characters and therefore result in failed > matches for expressions that rely on that extention, for ex: > > $ git grep -P '\bÆvar' > > Add PCRE2_UCP so that \w will include Æ and therefore \b could > correctly match the beginning of that word. > > This has an impact on performance that has been estimated to be > between 20% to 40% and that is shown through the added performance > test. > > Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> > --- > grep.c | 2 +- > t/perf/p7822-grep-perl-character.sh | 42 +++++++++++++++++++++++++++++ > 2 files changed, 43 insertions(+), 1 deletion(-) > create mode 100755 t/perf/p7822-grep-perl-character.sh > > diff --git a/grep.c b/grep.c > index 06eed69493..1687f65b64 100644 > --- a/grep.c > +++ b/grep.c > @@ -293,7 +293,7 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt > options |= PCRE2_CASELESS; > } > if (!opt->ignore_locale && is_utf8_locale() && !literal) > - options |= (PCRE2_UTF | PCRE2_MATCH_INVALID_UTF); > + options |= (PCRE2_UTF | PCRE2_UCP | PCRE2_MATCH_INVALID_UTF); I have a definite bias towards liking this change, it would help my find myself :) But I don't think it's safe to change the default behavior "git-grep", it's not a mere bug fix, but a major behavior change for existing users of grep.patternType=perl. E.g. on git.git: $ diff <(git -P grep -P '\d+') <(git -P grep -P '(*UCP)\d') 53360a53361,53362 > git-gui/po/ja.po:"- 第1行: 何をしたか、を1行で要約。\n" > git-gui/po/ja.po:"- 第2行: 空白\n" So, it will help "do the right thing" on e.g. "\bÆ", but it will also find e.g. CJK numeric characters for \d etc. I see per the discussion on https://github.com/PCRE2Project/pcre2/issues/185 and https://lists.gnu.org/archive/html/bug-grep/2023-01/threads.html that you submitted similar fixes to GNU grep & PCRE itself. I see that GNU grep integrated it a couple of days ago as https://git.savannah.gnu.org/cgit/grep.git/commit/?id=5e3b760f65f13856e5717e5b9d935f5b4a615be3 As most discussions about PCRE will eventually devolve into "what does Perl do?": "Perl" itself will promiscuously use this behavior by default. E.g. here the same "1" character (not the ASCII digit "1") will be matched from the command-line: $ perl -Mre=debug -CA -wE 'shift =~ /\d/' "1" Compiling REx "\d" Final program: 1: POSIXU[\d] (2) 2: END (0) stclass POSIXU[\d] minlen 1 Matching REx "\d" against "%x{ff11}" UTF-8 string... Matching stclass POSIXU[\d] against "%x{ff11}" (3 bytes) 0 <> <%x{ff11}> | 0| 1:POSIXU[\d](2) 3 <%x{ff11}> <> | 0| 2:END(0) Match successful! Freeing REx: "\d" But I don't think it makes sense for "git grep" (or GNU "grep") to follow Perl in this particular case. For those not familiar with its Unicode model it doesn't assume by default that strings are Unicode, they have to be explicitly marked as such. in the above example I'm declaring that all of "argv" is UTF-8 (via the "-CA" flag). If I didn't supply that flag the string wouldn't have the UTF-8 flag, and wouldn't match, as the Perl regex engine won't use Unicode semantics except on Unicode target strings. Even for Perl, this behavior has been troublesome. Opinions differ, but I think many would agree (and I've CC'd the main authority on Perl's regex engine) that doing this by default was *probably* a mistake. You almost never want "everything Unicode considers a digit", and if you do using e.g. \p{Nd} instead of \d would be better in terms of expressing your intent. I see you're running into this on the PCRE tracker, where you're suggesting that the equivalent of /a (or /aa) would be needed. https://github.com/PCRE2Project/pcre2/issues/185#issuecomment-1374796393 Which brings me home to the seeming digression about "Perl" above. Unlike a programming language where you'll typically "mark" your data as it comes in, natural text as UTF-8, binary data as such etc., a "grep" utility has to operate on more of an "all or nothing" basis (except in the case of "-a"). I.e. we're usually searching through unknown data. Enabling this by default means that we'll pick up characters most people probably wouldn't expect, particularly from near-binary data formats (those that won't require "-a", but contain non-Unicode non-ASCII sequences). I don't have some completely holistic view of what we should do in every case, e.g. we turned on PCRE2_UTF so that things like "-i" would Just Work, but even case-insensitivity has its own unexpected edge cases in Unicode. But I don't think those edge cases are nearly as common as those we'd run into by enabling PCRE2_UCP. Rather than trying to opt-out with "/a" or "/aa" I think this should be opt-in. As the example at the start shows you can already do this with "(*UCP)" in the pattern, so perhaps we should just link to the pcre2pattern(3) manual from git-grep(1)? ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: [PATCH v2] grep: correctly identify utf-8 characters with \{b, w} in -P 2023-01-09 11:35 ` Ævar Arnfjörð Bjarmason @ 2023-01-09 18:40 ` Paul Eggert 2023-01-09 19:51 ` Ævar Arnfjörð Bjarmason 2023-01-10 4:49 ` [PATCH v2] grep: correctly identify utf-8 characters with \{b,w} " Carlo Arenas ` (2 subsequent siblings) 3 siblings, 1 reply; 36+ messages in thread From: Paul Eggert @ 2023-01-09 18:40 UTC (permalink / raw) To: Ævar Arnfjörð Bjarmason, Carlo Marcelo Arenas Belón Cc: demerphq, pcre-dev, 60690, gitster, git On 1/9/23 03:35, Ævar Arnfjörð Bjarmason wrote: > You almost never want "everything Unicode considers a digit", and if you > do using e.g. \p{Nd} instead of \d would be better in terms of > expressing your intent. For GNU grep, PCRE2_UCP is needed because of examples like what Gro-Tsen and Karl Petterssen supplied. If there's some diagreement about how \d should behave with UTF-8 data the GNU grep hackers should let the Perl community decide that; that is, GNU grep can simply follow PCRE2's lead. But GNU grep does need PCRE2_UCP for \b etc. > $ diff <(git -P grep -P '\d+') <(git -P grep -P '(*UCP)\d') > 53360a53361,53362 > > git-gui/po/ja.po:"- 第1行: 何をしたか、を1行で要約。\n" > > git-gui/po/ja.po:"- 第2行: 空白\n" Although I don't speak Japanese I have dealt with quite a bit of Japanese text in a previous job, and personally I would prefer \d to match those two lines as they do contain digits. So to me this particular case is not a good argument that git grep should not match those lines. Of course other people might prefer differently, and there are cases where I want to match only ASCII digits. I've learned in the past to use [0-9] for that. I hope PCRE2 never changes [0-9] to match anything but ASCII digits when searching UTF-8 text. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: [PATCH v2] grep: correctly identify utf-8 characters with \{b, w} in -P 2023-01-09 18:40 ` bug#60690: [PATCH v2] grep: correctly identify utf-8 characters with \{b, w} " Paul Eggert @ 2023-01-09 19:51 ` Ævar Arnfjörð Bjarmason 2023-01-09 23:12 ` Paul Eggert 0 siblings, 1 reply; 36+ messages in thread From: Ævar Arnfjörð Bjarmason @ 2023-01-09 19:51 UTC (permalink / raw) To: Paul Eggert Cc: Carlo Marcelo Arenas Belón, demerphq, pcre-dev, 60690, gitster, git On Mon, Jan 09 2023, Paul Eggert wrote: > On 1/9/23 03:35, Ævar Arnfjörð Bjarmason wrote: > >> You almost never want "everything Unicode considers a digit", and if you >> do using e.g. \p{Nd} instead of \d would be better in terms of >> expressing your intent. > > For GNU grep, PCRE2_UCP is needed because of examples like what > Gro-Tsen and Karl Petterssen supplied. [For reference, referring to this Twitter thread: https://twitter.com/gro_tsen/status/1610972356972875777] Those examples compared -E and -P. I think it's correct that UCP brings the behavior closer to -E, but it's also different in various ways. E.g. on emacs.git (which I've been finding to be quite a nice test case) a comparison of the two, with "git grep" because I found it easier to test, but GNU grep will presumably find the same for those files: for c in b s w do for pfx in '' '(*UCP)' do echo "$pfx/$c:" && diff -u <(git -P grep -E "\\$c") <(git -P grep -P "$pfx\\$c") | wc -l done done Yields: /b: 155781 (*UCP)/b: 46035 /s: 0 (*UCP)/s: 0 /w: 142468 (*UCP)/w: 9706 So the output still differs, and some of those differences may or may not be wanted. > If there's some diagreement > about how \d should behave with UTF-8 data the GNU grep hackers should > let the Perl community decide that; that is, GNU grep can simply > follow PCRE2's lead. PCRE2 tends to follow Perl, I'm mainly trying to point out here that it isn't a-priory clear how "let Perl decide" is supposed to map to the of a "grep"-like utility, since the Perl behavior is inherently tied up with knowing the encoding of the target data. For GNU grep and "git grep" that's more of an all-or-nothing with locales, although in this case being as close as possible to -E is probably more correct than not. >> $ diff <(git -P grep -P '\d+') <(git -P grep -P '(*UCP)\d') >> 53360a53361,53362 >> > git-gui/po/ja.po:"- 第1行: 何をしたか、を1行で要約。\n" >> > git-gui/po/ja.po:"- 第2行: 空白\n" > > Although I don't speak Japanese I have dealt with quite a bit of > Japanese text in a previous job, and personally I would prefer \d to > match those two lines as they do contain digits. So to me this > particular case is not a good argument that git grep should not match > those lines. I'm mainly raising the backwards compatibility concern, which GNU grep and git grep may or may not want to handle differently, but let's at least be aware of the various edge cases. For \b I think it mostly does the right thing. For \w and \d in particular I'm mainly noting that yes, sometimes you want to match [0-9], and sometimes you'd want to match Japanese numbers, but you rarely (or at least I haven't) want to match everything Unicode considers X, unless you're doing some self-reflection on Unicode itself. E.g. for \d it's at least (up from just 10): $ perl -CO -wE 'for (1..2**20) { say chr if chr =~ /\d/ }'|wc -l 650 For \w you similarly go from ~60 to ~130k: $ perl -CO -wE 'for (1..2**24) { say chr if chr =~ /\w/ }'|wc -l 134564 If all you're doing is matching either ASCII or Japanese text and you want "locale-aware numbers" it might do the wrong thing. But I've found it to be too promiscuous when casting a wider net, which is the usual use-case with 'grep". > Of course other people might prefer differently, and there are cases > where I want to match only ASCII digits. I've learned in the past to > use [0-9] for that. I hope PCRE2 never changes [0-9] to match anything > but ASCII digits when searching UTF-8 text. I think that'll never change. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: [PATCH v2] grep: correctly identify utf-8 characters with \{b, w} in -P 2023-01-09 19:51 ` Ævar Arnfjörð Bjarmason @ 2023-01-09 23:12 ` Paul Eggert 0 siblings, 0 replies; 36+ messages in thread From: Paul Eggert @ 2023-01-09 23:12 UTC (permalink / raw) To: Ævar Arnfjörð Bjarmason Cc: Carlo Marcelo Arenas Belón, demerphq, pcre-dev, 60690, gitster, git On 1/9/23 11:51, Ævar Arnfjörð Bjarmason wrote: > /b: > 155781 > (*UCP)/b: > 46035 > /s: > 0 > (*UCP)/s: > 0 > /w: > 142468 > (*UCP)/w: > 9706 > > So the output still differs, and some of those differences may or may > not be wanted. I took a look at the output, and by and large I'd want the differences; that is, I'd want the UCP version, which generates less output. This is because several Emacs source files are not UTF-8, and \b has nonsense matches when searching text files encoded via Shift-JIS or Big 5 or whatever. For this sort of thing, the fewer matches the better. > If all you're doing is matching either ASCII or Japanese text and you > want "locale-aware numbers" it might do the wrong thing. I'm not seeing much of a problem here. When searching Japanese text, I would expect \d and [0-90-9] (using both ASCII and full-width digits) to be equivalent so (assuming UCP) it's not a big deal as to which regex you use, since Japanese text won't contain Bengali (or whatever) digits. And when searching binary data, I'd expect a bunch of garbage no matter how \d is interpreted. Here I'm assuming [0-9] (using full-width digits) has the expected meaning in PCRE2, i.e., that PCRE2 didn't make the same mistake that POSIX made. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [PATCH v2] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-09 11:35 ` Ævar Arnfjörð Bjarmason 2023-01-09 18:40 ` bug#60690: [PATCH v2] grep: correctly identify utf-8 characters with \{b, w} " Paul Eggert @ 2023-01-10 4:49 ` Carlo Arenas 2023-01-16 20:48 ` Junio C Hamano 2023-04-03 21:38 ` -P '\d' in GNU and git grep Paul Eggert 3 siblings, 0 replies; 36+ messages in thread From: Carlo Arenas @ 2023-01-10 4:49 UTC (permalink / raw) To: Ævar Arnfjörð Bjarmason; +Cc: git, gitster, demerphq On Mon, Jan 9, 2023 at 4:17 AM Ævar Arnfjörð Bjarmason <avarab@gmail.com> wrote: >Rather than trying to opt-out with "/a" or "/aa" I think this should be opt-in. > > As the example at the start shows you can already do this with "(*UCP)" > in the pattern, so perhaps we should just link to the pcre2pattern(3) > manual from git-grep(1)? Considering that PCRE is used internally even for cases that don't specify -P how would that opt-in work? For example, in a repository with code that uses utf identifiers, the following will fail: $ git grep -w -E motion u.c: int émotion = 0; $ git grep -w -E '(*UCP)motion' fatal: command line, '(*UCP)motion': Invalid preceding regular expression $ git -P grep -P -w '(*UCP)motion' u.c: int émotion = 0; Carlo CC removed gnu and the obsoleted PCRE developer list (if really needed would be better to use the documented pcre2-dev@googlegroups.com, instead) ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [PATCH v2] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-09 11:35 ` Ævar Arnfjörð Bjarmason 2023-01-09 18:40 ` bug#60690: [PATCH v2] grep: correctly identify utf-8 characters with \{b, w} " Paul Eggert 2023-01-10 4:49 ` [PATCH v2] grep: correctly identify utf-8 characters with \{b,w} " Carlo Arenas @ 2023-01-16 20:48 ` Junio C Hamano 2023-04-03 21:38 ` -P '\d' in GNU and git grep Paul Eggert 3 siblings, 0 replies; 36+ messages in thread From: Junio C Hamano @ 2023-01-16 20:48 UTC (permalink / raw) To: Ævar Arnfjörð Bjarmason Cc: Carlo Marcelo Arenas Belón, git Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes: > But I don't think it's safe to change the default behavior "git-grep", > it's not a mere bug fix, but a major behavior change for existing users > of grep.patternType=perl. > ... > Even for Perl, this behavior has been troublesome. Opinions differ, but > I think many would agree (and I've CC'd the main authority on Perl's > regex engine) that doing this by default was *probably* a mistake. > ... > As the example at the start shows you can already do this with "(*UCP)" > in the pattern, so perhaps we should just link to the pcre2pattern(3) > manual from git-grep(1)? So, now do we have a final verdict on this patch? If we are not taking the "unconditonally enable ucp" patch (which I tend to agree with a safer choice for now), it may make sense to mention (*UCP) in our documentation somewhere, perhaps? ^ permalink raw reply [flat|nested] 36+ messages in thread
* -P '\d' in GNU and git grep @ 2023-04-03 21:38 ` Paul Eggert 2023-04-04 3:30 ` bug#60690: " Jim Meyering 2023-04-04 6:56 ` Carlo Arenas 0 siblings, 2 replies; 36+ messages in thread From: Paul Eggert @ 2023-04-03 21:38 UTC (permalink / raw) To: 60690 Cc: Tukusej’s Sirs, Ævar Arnfjörð Bjarmason, mega lith01, demerphq, Carlo Marcelo Arenas Belón, pcre-dev, gitster, git I've recently done some bug-report maintenance about a set of GNU grep bug reports related to whether whether "grep -P '\d'" should match non-ASCII digits, and have some thoughts about coordinating GNU grep with git grep in this department. GNU Bug#62605[1] "`[\d]` does not work with PCRE" has been fixed on Savannah's copy of GNU grep, and some sort of fix should appear in the next grep release. However, I'm leaving the GNU grep bug report open for now because it's related to Bug#60690[2] "[PATCH v2] grep: correctly identify utf-8 characters with \{b,w} in -P" and to Bug#62552[3] "Bug found in latest stable release v3.10 of grep". I merged these related bug reports, and the oldest one, Bug#60690, is now the representative displayed in the GNU grep bug list[4]. For this set of grep bug reports there's still a pending issue discussed in my recent email[5], which proposes a patch so I've tagged Bug#60690 with "patch". The proposal is that GNU grep -P '\d' should revert to the grep 3.9 behavior, i.e., that in a UTF-8 locale, \d should also match non-ASCII decimal digits. In researching this a bit further, I found that on March 23 Git disabled the use of PCRE2_UCP in PCRE2 10.34 or earlier[6], due to a PCRE2 bug that can cause a crash when PCRE2_UCP is used[7]. A bug fix[8] should appear in the next PCRE2 release. When PCRE2 10.35 comes out, it appears that 'git grep -P' will behave like 'grep -P' only if GNU grep adopts something like the solution proposed in [5]. [1]: https://bugs.gnu.org/62605 [2]: https://bugs.gnu.org/60690 [3]: https://bugs.gnu.org/62552 [4]: https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep [5]: https://lists.gnu.org/archive/html/grep-devel/2023-04/msg00004.html [6]: https://github.com/git/git/commit/14b9a044798ebb3858a1f1a1377309a3d6054ac8 [7]: https://lore.kernel.org/git/7E83DAA1-F9A9-4151-8D07-D80EA6D59EEA@clumio.com/ [8]: https://github.com/git/git/commit/14b9a044798ebb3858a1f1a1377309a3d6054ac8 ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-03 21:38 ` -P '\d' in GNU and git grep Paul Eggert @ 2023-04-04 3:30 ` Jim Meyering 2023-04-04 6:46 ` Paul Eggert 2023-04-04 6:56 ` Carlo Arenas 1 sibling, 1 reply; 36+ messages in thread From: Jim Meyering @ 2023-04-04 3:30 UTC (permalink / raw) To: Paul Eggert Cc: 60690, demerphq, mega lith01, Carlo Marcelo Arenas Belón, Ævar Arnfjörð Bjarmason, git, gitster, Tukusej’s Sirs, pcre-dev On Mon, Apr 3, 2023 at 2:39 PM Paul Eggert <eggert@cs.ucla.edu> wrote: > I've recently done some bug-report maintenance about a set of GNU grep > bug reports related to whether whether "grep -P '\d'" should match > non-ASCII digits, and have some thoughts about coordinating GNU grep > with git grep in this department. > > GNU Bug#62605[1] "`[\d]` does not work with PCRE" has been fixed on > Savannah's copy of GNU grep, and some sort of fix should appear in the > next grep release. However, I'm leaving the GNU grep bug report open for > now because it's related to Bug#60690[2] "[PATCH v2] grep: correctly > identify utf-8 characters with \{b,w} in -P" and to Bug#62552[3] "Bug > found in latest stable release v3.10 of grep". I merged these related > bug reports, and the oldest one, Bug#60690, is now the representative > displayed in the GNU grep bug list[4]. > > For this set of grep bug reports there's still a pending issue discussed > in my recent email[5], which proposes a patch so I've tagged Bug#60690 > with "patch". The proposal is that GNU grep -P '\d' should revert to the > grep 3.9 behavior, i.e., that in a UTF-8 locale, \d should also match > non-ASCII decimal digits. > > In researching this a bit further, I found that on March 23 Git disabled > the use of PCRE2_UCP in PCRE2 10.34 or earlier[6], due to a PCRE2 bug > that can cause a crash when PCRE2_UCP is used[7]. A bug fix[8] should > appear in the next PCRE2 release. > > When PCRE2 10.35 comes out, Thanks for finding that. It's clearly a good idea to disable PCRE2_UCP for those using those older, known-buggy versions of pcre2. The latest is 10.42, per https://github.com/PCRE2Project/pcre2/releases > it appears that 'git grep -P' will behave > like 'grep -P' only if GNU grep adopts something like the solution > proposed in [5]. > > [1]: https://bugs.gnu.org/62605 > [2]: https://bugs.gnu.org/60690 > [3]: https://bugs.gnu.org/62552 > [4]: https://debbugs.gnu.org/cgi/pkgreport.cgi?package=grep > [5]: https://lists.gnu.org/archive/html/grep-devel/2023-04/msg00004.html > [6]: > https://github.com/git/git/commit/14b9a044798ebb3858a1f1a1377309a3d6054ac8 > [7]: > https://lore.kernel.org/git/7E83DAA1-F9A9-4151-8D07-D80EA6D59EEA@clumio.com/ > [8]: > https://github.com/git/git/commit/14b9a044798ebb3858a1f1a1377309a3d6054ac8 Thanks for all of the links. However, have you seen justification (other than for compatibility with some other tool or language) for allowing \d to match non-ASCII by default, in spite of the risks? IMHO, we have an obligation to retain compatibility with how grep -P '\d' has worked since -P was added. I'd be happy to see an option to enable the match-multibyte-digits behavior, but making it the default seems too likely to introduce unwarranted risk. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-04 3:30 ` bug#60690: " Jim Meyering @ 2023-04-04 6:46 ` Paul Eggert 2023-04-04 15:31 ` Jim Meyering 0 siblings, 1 reply; 36+ messages in thread From: Paul Eggert @ 2023-04-04 6:46 UTC (permalink / raw) To: Jim Meyering Cc: 60690, demerphq, mega lith01, Carlo Marcelo Arenas Belón, Ævar Arnfjörð Bjarmason, git, gitster, Tukusej’s Sirs, pcre-dev On 2023-04-03 20:30, Jim Meyering wrote: > have you seen justification > (other than for compatibility with some other tool or language) for > allowing \d to match non-ASCII by default, in spite of the risks? In the example Ævar supplied in <https://bugs.gnu.org/60690>, my impression was that it was better when \d matched non-ASCII digits. That is, in a UTF-8 locale it's better when \d finds matches in these lines: >> > git-gui/po/ja.po:"- 第1行: 何をしたか、を1行で要約。\n" >> > git-gui/po/ja.po:"- 第2行: 空白\n" because they contain the Japanese digits "1" and "2". This was the only example I recall being given. Also, I find it odd that grep -P '^[\w\d]*$' matches lines containing any sort of Arabic word characters, but it rejects lines containing Arabic digits like "٣" that are perfectly reasonable in Arabic-language text. I also find it odd that [\d] and [[:digit:]] mean different things. There are arguments on the other side, otherwise we wouldn't be having this discussion. And it's true that grep -P '\d' formerly rejected Arabic digits (though it's also true that grep -P '\w' formerly rejected Arabic letters...). Still, the cure's oddness and incompatibility with Git, Perl, etc. appears to me to be worse than the disease of dealing with grep -P invocations that need to use [0-9] or LC_ALL="C" anyway if they want to be portable to any program other than GNU grep. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-04 6:46 ` Paul Eggert @ 2023-04-04 15:31 ` Jim Meyering 0 siblings, 0 replies; 36+ messages in thread From: Jim Meyering @ 2023-04-04 15:31 UTC (permalink / raw) To: Paul Eggert Cc: 60690, demerphq, mega lith01, Carlo Marcelo Arenas Belón, Ævar Arnfjörð Bjarmason, git, gitster, Tukusej’s Sirs, pcre-dev On Mon, Apr 3, 2023 at 11:47 PM Paul Eggert <eggert@cs.ucla.edu> wrote: > On 2023-04-03 20:30, Jim Meyering wrote: > > have you seen justification > > (other than for compatibility with some other tool or language) for > > allowing \d to match non-ASCII by default, in spite of the risks? > > In the example Ævar supplied in <https://bugs.gnu.org/60690>, my > impression was that it was better when \d matched non-ASCII digits. That > is, in a UTF-8 locale it's better when \d finds matches in these lines: > > >> > git-gui/po/ja.po:"- 第1行: 何をしたか、を1行で要約。\n" > >> > git-gui/po/ja.po:"- 第2行: 空白\n" > > because they contain the Japanese digits "1" and "2". This was the only > example I recall being given. Before it was unintentionally enabled in grep-3.9, lines like that have never been matched by grep -P's '\d'. By relaxing \d, we'd weaken any application that uses say grep -P '^\d+$' to perform input validation intending to ensure that some input is all ASCII digits. It's not a big stretch to imagine that some downstream processor of that "verified" data is not prepared to deal with multi-byte digits. > Also, I find it odd that grep -P '^[\w\d]*$' matches lines containing > any sort of Arabic word characters, but it rejects lines containing > Arabic digits like "٣" that are perfectly reasonable in Arabic-language > text. I also find it odd that [\d] and [[:digit:]] mean different things. > > There are arguments on the other side, otherwise we wouldn't be having > this discussion. And it's true that grep -P '\d' formerly rejected > Arabic digits (though it's also true that grep -P '\w' formerly rejected > Arabic letters...). Still, the cure's oddness and incompatibility with > Git, Perl, etc. appears to me to be worse than the disease of dealing > with grep -P invocations that need to use [0-9] or LC_ALL="C" anyway if > they want to be portable to any program other than GNU grep. I'm primarily concerned about not introducing a persistent regression in how GNU grep's -P '\d' works in multibyte locales. The corner cases you mention do matter, of course, but are far less likely to matter in practice. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: -P '\d' in GNU and git grep 2023-04-03 21:38 ` -P '\d' in GNU and git grep Paul Eggert 2023-04-04 3:30 ` bug#60690: " Jim Meyering @ 2023-04-04 6:56 ` Carlo Arenas 2023-04-04 18:25 ` bug#60690: " Paul Eggert 1 sibling, 1 reply; 36+ messages in thread From: Carlo Arenas @ 2023-04-04 6:56 UTC (permalink / raw) To: Paul Eggert Cc: 60690, Tukusej’s Sirs, Ævar Arnfjörð Bjarmason, mega lith01, demerphq, pcre-dev, gitster, git On Mon, Apr 3, 2023 at 2:38 PM Paul Eggert <eggert@cs.ucla.edu> wrote: > > In researching this a bit further, I found that on March 23 Git disabled > the use of PCRE2_UCP in PCRE2 10.34 or earlier[6], due to a PCRE2 bug > that can cause a crash when PCRE2_UCP is used[7]. A bug fix[8] should > appear in the next PCRE2 release. Presume PCRE2 is a typo and should have been "git" here? FWIW the PCRE2 fix[1] has been released already with 10.35 and backporting to the Ubuntu 20.04 package that crashed in the original report would also solve the crash with 10.34. Carlo [1] https://github.com/PCRE2Project/pcre2/commit/c21bd977547d ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-04 6:56 ` Carlo Arenas @ 2023-04-04 18:25 ` Paul Eggert 2023-04-04 19:31 ` Junio C Hamano 0 siblings, 1 reply; 36+ messages in thread From: Paul Eggert @ 2023-04-04 18:25 UTC (permalink / raw) To: Carlo Arenas Cc: demerphq, 60690, mega lith01, Ævar Arnfjörð Bjarmason, git, gitster, Tukusej’s Sirs, pcre-dev On 4/3/23 23:56, Carlo Arenas wrote: > On Mon, Apr 3, 2023 at 2:38 PM Paul Eggert <eggert@cs.ucla.edu> wrote: >> >> on March 23 Git disabled >> the use of PCRE2_UCP in PCRE2 10.34 or earlier[6], due to a PCRE2 bug >> that can cause a crash when PCRE2_UCP is used[7]. A bug fix[8] should >> appear in the next PCRE2 release. > > Presume PCRE2 is a typo and should have been "git" here? No, I was talking about what options Git uses when it calls PCRE2 functions. In other words, this is about whether GNU 'grep -P' should be compatible with 'git grep -P' (as well as with Perl and with pcregrep), when interpreting \d and similar constructs. This is an evolving area. Git master is fiddling with flags and options, and so is GNU grep master, and so is PCRE2, and there are bugs. If you're running bleeding-edge versions of this code you'll get different behavior than if you're running grep 3.8, pcregrep 8.45, Perl 5.36, and git 2.39.2 (which is what Fedora 37 has). What I'm fearing is that we may evolve into mutually incompatible interpretations of how Perl regular expressions deal with UTF-8 text. That'd be a recipe for confusion down the road. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-04 18:25 ` bug#60690: " Paul Eggert @ 2023-04-04 19:31 ` Junio C Hamano 2023-04-05 18:32 ` Paul Eggert 2023-04-06 13:39 ` demerphq 0 siblings, 2 replies; 36+ messages in thread From: Junio C Hamano @ 2023-04-04 19:31 UTC (permalink / raw) To: Paul Eggert Cc: Carlo Arenas, demerphq, 60690, mega lith01, Ævar Arnfjörð Bjarmason, git, Tukusej’s Sirs, pcre-dev Paul Eggert <eggert@cs.ucla.edu> writes: > This is an evolving area. Git master is fiddling with flags and > options, and so is GNU grep master, and so is PCRE2, and there are > bugs. If you're running bleeding-edge versions of this code you'll get > different behavior than if you're running grep 3.8, pcregrep 8.45, > Perl 5.36, and git 2.39.2 (which is what Fedora 37 has). > > What I'm fearing is that we may evolve into mutually incompatible > interpretations of how Perl regular expressions deal with UTF-8 > text. That'd be a recipe for confusion down the road. Nicely said. My personal inclination is to let Perl folks decide and follow them (even though I am skeptical about the wisdom of letting '\d' match anything other than [0-9]), but even in Git circle there would be different opinions, so I am glad that the discussion is visible on the list to those who are intrested. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-04 19:31 ` Junio C Hamano @ 2023-04-05 18:32 ` Paul Eggert 2023-04-05 19:04 ` Paul Eggert ` (3 more replies) 2023-04-06 13:39 ` demerphq 1 sibling, 4 replies; 36+ messages in thread From: Paul Eggert @ 2023-04-05 18:32 UTC (permalink / raw) To: Junio C Hamano Cc: Carlo Arenas, demerphq, 60690, mega lith01, Ævar Arnfjörð Bjarmason, git, Tukusej’s Sirs, pcre-dev, Philip.Hazel On 2023-04-04 12:31, Junio C Hamano wrote: > My personal inclination is to let Perl folks decide > and follow them (even though I am skeptical about the wisdom of > letting '\d' match anything other than [0-9]) I looked into what pcre2grep does. It has always done only 8-bit processing unless you use the -u or --utf option, so plain "pcre2grep '\d'" matches only ASCII digits. Although this causes pcre2grep to mishandle Unicode characters: $ echo 'Ævar' | pcre2grep '[Ssß]' Ævar it mimics Perl 5.36: $ echo 'Ævar' | perl -ne 'print $_ if /[Ssß]/' Ævar so this seems to be what Perl users expect, despite its infelicities. For better Unicode handling one can use pcre2grep's -u or --utf option, which causes pcre2grep to behave more like GNU grep -P and git grep -P: "echo 'Ævar' | pcre2grep -u '[Ssß]'" outputs nothing, which I think is what most people would expect (unless they're Perl users :-). Neither git grep -P nor the current release of pcre2grep -u have \d matching non-ASCII digits, because they do not use PCRE2_UCP. However, in a February 8 commit[1], Philip Hazel changed pcre2grep to use PCRE2_UCP, so this will mean 10.43 pcre2grep -u will behave like 3.9 GNU grep -P did (though 3.10 has changed this). That February commit also added a --no-ucp option, to disable PCRE2_UCP. So as I understand it, if you're in a UTF-8 locale: * 10.43 pcre2grep -u will behave like 3.9 GNU grep -P. * 10.43 pcre2grep -u --no-ucp will behave like git grep -P. * Current GNU grep -P is different from everybody else. This incompatibility is not good. Here are two ways forward to fix this incompatibility (there are other possibilities of course): (A) GNU grep adds a --no-ucp option that acts like 10.43 pcre2grep --no-ucp, and git grep -P follows suit. That is, both GNU and git grep act like 10.43 pcre2grep -u, in that they enable PCRE2_UTF, and also enable PCRE2_UCP unless --no-ucp is given. This would cause \d to match non-ASCII digits unless --no-ucp is given. (B) GNU grep -P and git grep -P mimic pcre2grep in both -u and --no-ucp. That is, they would both do 8-bit-only by default, and use PCRE2_UTF only when -u or --utf is given, and use PCRE2_UCP only when --no-ucp is absent. This would cause \d to match non-ASCII digits only when -u is given but --no-ucp is not. Under either (A) or (B), future pcre2grep -u, GNU grep -P, and git grep -P would be consistent. I mildly prefer (B) but (A) would also work. (One advantage of (B) is that it should be faster....) [1]: https://github.com/PCRE2Project/pcre2/commit/8385df8c97b6f8069a48e600c7e4e94cc3e3ebd9ht ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-05 18:32 ` Paul Eggert @ 2023-04-05 19:04 ` Paul Eggert 2023-04-05 19:37 ` Junio C Hamano ` (2 subsequent siblings) 3 siblings, 0 replies; 36+ messages in thread From: Paul Eggert @ 2023-04-05 19:04 UTC (permalink / raw) To: Junio C Hamano Cc: demerphq, Philip.Hazel, 60690, mega lith01, Carlo Arenas, Ævar Arnfjörð Bjarmason, pcre-dev, Tukusej’s Sirs, git On 2023-04-05 11:32, Paul Eggert wrote: > in a February 8 commit[1], Philip Hazel changed pcre2grep to use > PCRE2_UCP, so this will mean 10.43 pcre2grep -u will behave like 3.9 GNU > grep -P did (though 3.10 has changed this). Sorry, due to fumblefingers I gave the wrong URL for [1]. Here's a corrected URL: https://github.com/PCRE2Project/pcre2/commit/8385df8c97b6f8069a48e600c7e4e94cc3e3ebd9 It also mentions a new --case-restrict option, intended for 10.43 pcre2grep. Given Perl's and PCRE2's plethora of options I suppose one could imagine several other options of that ilk. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-05 18:32 ` Paul Eggert 2023-04-05 19:04 ` Paul Eggert @ 2023-04-05 19:37 ` Junio C Hamano 2023-04-05 19:40 ` Jim Meyering 2023-04-06 15:45 ` demerphq 3 siblings, 0 replies; 36+ messages in thread From: Junio C Hamano @ 2023-04-05 19:37 UTC (permalink / raw) To: Paul Eggert Cc: Carlo Arenas, demerphq, 60690, mega lith01, Ævar Arnfjörð Bjarmason, git, Tukusej’s Sirs, pcre-dev, Philip.Hazel Paul Eggert <eggert@cs.ucla.edu> writes: > Here are two ways forward to fix this incompatibility (there are other > possibilities of course): > > (A) GNU grep adds a --no-ucp option that acts like 10.43 pcre2grep > --no-ucp, and git grep -P follows suit. That is, both GNU and git grep > act like 10.43 pcre2grep -u, in that they enable PCRE2_UTF, and also > enable PCRE2_UCP unless --no-ucp is given. This would cause \d to > match non-ASCII digits unless --no-ucp is given. > > (B) GNU grep -P and git grep -P mimic pcre2grep in both -u and > --no-ucp. That is, they would both do 8-bit-only by default, and use > PCRE2_UTF only when -u or --utf is given, and use PCRE2_UCP only when > --no-ucp is absent. This would cause \d to match non-ASCII digits only > when -u is given but --no-ucp is not. > > Under either (A) or (B), future pcre2grep -u, GNU grep -P, and git > grep -P would be consistent. > > I mildly prefer (B) but (A) would also work. (One advantage of (B) is > that it should be faster....) For "git grep -P", I would like to hear from Carlo and Ævar; I agree both (A) and (B) would be workable solutions, and have a slight preference on a solution that does not add more options that take only in effect when -P is given, simply because these options are cumbersome to document and explain, but that is a very minor point. Thanks. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-05 18:32 ` Paul Eggert 2023-04-05 19:04 ` Paul Eggert 2023-04-05 19:37 ` Junio C Hamano @ 2023-04-05 19:40 ` Jim Meyering 2023-04-05 20:03 ` Paul Eggert 2023-04-05 21:20 ` Carlo Arenas 2023-04-06 15:45 ` demerphq 3 siblings, 2 replies; 36+ messages in thread From: Jim Meyering @ 2023-04-05 19:40 UTC (permalink / raw) To: Paul Eggert Cc: Junio C Hamano, demerphq, Philip.Hazel, 60690, mega lith01, Carlo Arenas, Ævar Arnfjörð Bjarmason, pcre-dev, Tukusej’s Sirs, git On Wed, Apr 5, 2023 at 11:33 AM Paul Eggert <eggert@cs.ucla.edu> wrote: > On 2023-04-04 12:31, Junio C Hamano wrote: > > My personal inclination is to let Perl folks decide > > and follow them (even though I am skeptical about the wisdom of > > letting '\d' match anything other than [0-9]) > > I looked into what pcre2grep does. It has always done only 8-bit > processing unless you use the -u or --utf option, so plain "pcre2grep > '\d'" matches only ASCII digits. > > Although this causes pcre2grep to mishandle Unicode characters: > > $ echo 'Ævar' | pcre2grep '[Ssß]' > Ævar > > it mimics Perl 5.36: > > $ echo 'Ævar' | perl -ne 'print $_ if /[Ssß]/' > Ævar > > so this seems to be what Perl users expect, despite its infelicities. > > For better Unicode handling one can use pcre2grep's -u or --utf option, > which causes pcre2grep to behave more like GNU grep -P and git grep -P: > "echo 'Ævar' | pcre2grep -u '[Ssß]'" outputs nothing, which I think is > what most people would expect (unless they're Perl users :-). Good argument for making PCRE2_UCP the default. > Neither git grep -P nor the current release of pcre2grep -u have \d > matching non-ASCII digits, because they do not use PCRE2_UCP. However, > in a February 8 commit[1], Philip Hazel changed pcre2grep to use > PCRE2_UCP, so this will mean 10.43 pcre2grep -u will behave like 3.9 GNU > grep -P did (though 3.10 has changed this). > > That February commit also added a --no-ucp option, to disable PCRE2_UCP. > So as I understand it, if you're in a UTF-8 locale: > > * 10.43 pcre2grep -u will behave like 3.9 GNU grep -P. > > * 10.43 pcre2grep -u --no-ucp will behave like git grep -P. > > * Current GNU grep -P is different from everybody else. > > This incompatibility is not good. > > Here are two ways forward to fix this incompatibility (there are other > possibilities of course): > > (A) GNU grep adds a --no-ucp option that acts like 10.43 pcre2grep > --no-ucp, and git grep -P follows suit. That is, both GNU and git grep > act like 10.43 pcre2grep -u, in that they enable PCRE2_UTF, and also > enable PCRE2_UCP unless --no-ucp is given. This would cause \d to match > non-ASCII digits unless --no-ucp is given. > > (B) GNU grep -P and git grep -P mimic pcre2grep in both -u and --no-ucp. > That is, they would both do 8-bit-only by default, and use PCRE2_UTF > only when -u or --utf is given, and use PCRE2_UCP only when --no-ucp is > absent. This would cause \d to match non-ASCII digits only when -u is > given but --no-ucp is not. Changing grep -P's \d to match multibyte digits by default would break an important contract. Avoiding that feels like it must outweigh any cross-tool portability concern. (C) preserve grep -P's tradition of \d matching only 0..9, and once grep uses 10.43 or newer, \b and \w will also work as desired. > Under either (A) or (B), future pcre2grep -u, GNU grep -P, and git grep > -P would be consistent. I hope git grep -P's \d will also stick to ASCII-only by default. Those rare few who desire multibyte matches can always specify \p{Nd} instead of \d, or (with new enough PCRE2), use (?-aD) and (?aD) to toggle the digit-matching mode. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-05 19:40 ` Jim Meyering @ 2023-04-05 20:03 ` Paul Eggert 2023-04-05 21:20 ` Carlo Arenas 1 sibling, 0 replies; 36+ messages in thread From: Paul Eggert @ 2023-04-05 20:03 UTC (permalink / raw) To: Jim Meyering Cc: Junio C Hamano, demerphq, Philip.Hazel, 60690, mega lith01, Carlo Arenas, Ævar Arnfjörð Bjarmason, pcre-dev, Tukusej’s Sirs, git On 2023-04-05 12:40, Jim Meyering wrote: > (C) preserve grep -P's tradition of \d matching only 0..9, and once > grep uses 10.43 or newer, \b and \w will also work as desired. If I understand you correctly, (C) would mean that GNU grep -P, git grep -P, and pcre2grep -u would all use PCRE2_UTF | PCRE2_UCP, and would also use the extra option PCRE2_EXTRA_ASCII_BSD that is planned for 10.43 PCRE2. This would require changes to bleeding-edge pcre2grep -u (since it would need to add PCRE2_EXTRA_ASCII_BSD unless --no-ucp is also given), and to git grep -P (which would need to add PCRE2_UCP and PCRE2_EXTRA_ASCII_BSD, when libpcre2 is new enough to #define PCRE2_EXTRA_ASCII_BSD). This option works for me as well. In fact it's the least work for me since I already implemented it in bleeding-edge GNU grep (so it works this way already :-). ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-05 19:40 ` Jim Meyering 2023-04-05 20:03 ` Paul Eggert @ 2023-04-05 21:20 ` Carlo Arenas 1 sibling, 0 replies; 36+ messages in thread From: Carlo Arenas @ 2023-04-05 21:20 UTC (permalink / raw) To: Jim Meyering Cc: Paul Eggert, Junio C Hamano, demerphq, Philip.Hazel, 60690, mega lith01, Ævar Arnfjörð Bjarmason, Tukusej’s Sirs, git, pcre2-dev On Wed, Apr 5, 2023 at 12:40 PM Jim Meyering <jim@meyering.net> wrote: > > Changing grep -P's \d to match multibyte digits by default would break > an important contract. While I tend to agree[1] (and indeed that is why PCRE2_EXTRA_ASCII_BSD was invented), it would be also important to note that it goes against the Unicode recommendation[2] and it is actually not true already[3] for Python, .NET or Rust (which means ripgrep behaves like GNU grep -P 3.9). FWIW I also agree that (at least `git grep -P`) should use PCRE2_EXTRA_ASCII_BSD by default as that is what makes more sense in the context of matching source code and using instead `\P{Nd}` if you really want all Unicode digits is not much of a burden, but I am also not sure if that makes sense in other contexts, specially considering that I am obviously biased since the languages I mostly interact with ONLY use arabic numerals and therefore `\d` meaning `[0-9]` seems "normal". Carlo CC: changed to the real email address for PCRE2 development, for full context on this thread use [4] [1] https://github.com/PCRE2Project/pcre2/pull/186 [2] https://unicode.org/reports/tr18/ [3] https://regex101.com/r/S5RW4c/1 [4] https://lore.kernel.org/git/230109.86v8lf297g.gmgdl@evledraar.gmail.com/T/ ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-05 18:32 ` Paul Eggert ` (2 preceding siblings ...) 2023-04-05 19:40 ` Jim Meyering @ 2023-04-06 15:45 ` demerphq 2023-04-07 16:48 ` Paul Eggert 3 siblings, 1 reply; 36+ messages in thread From: demerphq @ 2023-04-06 15:45 UTC (permalink / raw) To: Paul Eggert Cc: Junio C Hamano, Carlo Arenas, 60690, mega lith01, Ævar Arnfjörð Bjarmason, git, Tukusej’s Sirs, pcre-dev, Philip.Hazel On Wed, 5 Apr 2023 at 20:32, Paul Eggert <eggert@cs.ucla.edu> wrote: > > On 2023-04-04 12:31, Junio C Hamano wrote: > > > My personal inclination is to let Perl folks decide > > and follow them (even though I am skeptical about the wisdom of > > letting '\d' match anything other than [0-9]) > > I looked into what pcre2grep does. It has always done only 8-bit > processing unless you use the -u or --utf option, so plain "pcre2grep > '\d'" matches only ASCII digits. > > Although this causes pcre2grep to mishandle Unicode characters: > > $ echo 'Ævar' | pcre2grep '[Ssß]' > Ævar > > it mimics Perl 5.36: > > $ echo 'Ævar' | perl -ne 'print $_ if /[Ssß]/' > Ævar > > so this seems to be what Perl users expect, despite its infelicities. Actually no, I think you have misunderstood what is happening at the different layers involved here. Your terminal is rendering ß as a glyph. But it is almost certainly actually the octets C3 9F (which is the UTF8 canonical representation of the codepoint U+DF). So the code you provided to perl is close to the equivalent of echo 'Ævar' | perl -ne 'print $_ if /[Ss\x{C3}\x{9F}]/' And if you check, you will see that U+C6 "Æ" in utf8 is represented as the octets C3 86. So what you have done is the equivalent of: perl -le'print "\x{C3}\x{86}"' | perl -ne'print $_ if /[Ss\x{C3}\x{9F}]/' which of course matches. \x{C3} matches \x{C3} always and everywhere. What you should have done is something like this: $ echo 'Ævar' | perl -ne 'utf8::decode($_); print $_ if /[Ss\x{DF}]/u' $ echo 'baß' | perl -MEncode -ne 'utf8::decode($_); print encode_utf8($_) if /[Ss\x{DF}]/u' baß $ echo 'Ævar' | perl -MEncode -ne 'utf8::decode($_); print encode_utf8($_) if /[Ss\x{C6}]/u' Ævar $ echo 'Ævar' | perl -MEncode -ne 'utf8::decode($_); print encode_utf8($_) if /[Ss\x{e6}]/ui' Ævar The "utf8::decode($_)" tells perl to decode the input string as though it contained utf8 (which in this case it does). THe /u suffix tells the regex engine that you want Unicode semantics. I believe that the same thing is true of your pcre2grep example. You simply aren't checking what you think you are checking. You terminal renders UTF8 as glyphs, but the programs you are feeding those glyphs to aren't seeing glyphs, they are seeing UTF8 sequences as distinct octets, and are not decoding their input back as codepoints. You could have checked your assumptions by using the -Mre=debug option to perl: $ echo 'Ævar' | perl -Mre=debug -ne 'print $_ if /[Ssß]/' Compiling REx "[Ss%x{c3}%x{9f}]" Final program: 1: ANYOF[Ss\x9F\xC3] (11) 11: END (0) stclass ANYOF[Ss\x9F\xC3] minlen 1 Matching REx "[Ss%x{c3}%x{9f}]" against "%x{c3}%x{86}var%n" Matching stclass ANYOF[Ss\x9F\xC3] against "%x{c3}%x{86}var%n" (6 bytes) 0 <> <%x{c3}> | 0| 1:ANYOF[Ss\x9F\xC3](11) 1 <%x{c3}> <%x{86}var> | 0| 11:END(0) Match successful! Ævar Freeing REx: "[Ss%x{c3}%x{9f}]" The line: Matching REx "[Ss%x{c3}%x{9f}]" against "%x{c3}%x{86}var%n" basically says it all. Perl has not decoded the UTF8 into U+C6, and it has not decoded the UTF8 for U+DF either. Instead you have asked it if the UTF8 sequence that represents U+C6 contains any of the same octets as the UTF8 representation of U+53, U+73 and U+DF would. Which gives the common octet of \x{c3}. > For better Unicode handling one can use pcre2grep's -u or --utf option, > which causes pcre2grep to behave more like GNU grep -P and git grep -P: > "echo 'Ævar' | pcre2grep -u '[Ssß]'" outputs nothing, which I think is > what most people would expect (unless they're Perl users :-). It is what Perl users would expect also, assuming you actually wrote the character class [Ss\x{DF}] and asked for unicode semantics. \x{DF} is the Latin1 codepoint range, so perl will assume that you meant ASCII semantics unless you tell it otherwise. Basically these tests you have quoted here are just examples of garbage in garbage out. Perl has been working together with the Unicode consortium for over 20 years. Afaik we were and are the reference implementation for the spec on regular expression matching in Unicode and we have a long history of working together with the Unicode consortium to refine and implement the spec. You should assume that if Perl seems to have made a gross error in how it does Unicode matching that you are simply using it wrong, we take a great deal of pride in having the best Unicode support there is. https://unicode.org/reports/tr18/ FWIW, i think this email nicely illustrates the issues with git and regular expressions. To do regular expressions properly you need to know a) what semantics do you expect, b) how to decode the text you are matching against. If you want unicode semantics you need to have a way to ask for it. If you want to match against Unicode data then you need a way to determine which of the 6 possible encodings[1] of Unicode data you are using. If you get either wrong you will not get the results you expect. You may even want to deal with cases where you want Unicode semantics, but to match against non-unicode data. For instance Latin-1. In Latin-1 the codepoint U+DF is the *octet* 0xDF. Maybe you want that octet to match "ss" case-insensitively, as a German speaker would expect and as Unicode specifies is correct. Or vice versa, maybe you are like some of the posters to this thread who seem to expect that \d should not match U+16B51 (as a Hmong speaker might expect). Perl resolves these problems at the pattern level by supporting the suffixes /a and /u (for ascii and unicode), and at the string level it supports two type of string, unicode strings, and binary/ASCII strings. By default input is the latter but there are a variety of ways of saying that a file handle should decode to Unicode instead. cheers, Yves [1] UTF-EBCDIC, UTF-8, UTF-16LE, UTF-16BE, UTF-32LE, UTF-32BE. -- perl -Mre=debug -e "/just|another|perl|hacker/" ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-06 15:45 ` demerphq @ 2023-04-07 16:48 ` Paul Eggert 0 siblings, 0 replies; 36+ messages in thread From: Paul Eggert @ 2023-04-07 16:48 UTC (permalink / raw) To: demerphq Cc: Philip.Hazel, 60690, mega lith01, Carlo Arenas, Ævar Arnfjörð Bjarmason, Junio C Hamano, pcre-dev, Tukusej’s Sirs, git On 2023-04-06 08:45, demerphq wrote: >> Although this causes pcre2grep to mishandle Unicode characters: >> >> $ echo 'Ævar' | pcre2grep '[Ssß]' >> Ævar >> >> it mimics Perl 5.36: >> >> $ echo 'Ævar' | perl -ne 'print $_ if /[Ssß]/' >> Ævar >> >> so this seems to be what Perl users expect, despite its infelicities. > Actually no, I think you have misunderstood what is happening at the > different layers involved here. No, I understood what was going on. My point was that Perl users seem to have accepted this behavior, even though it does not match what people would ordinarily expect. > What you should have done is something like this: No, for two reasons. First, I'm no Perl expert and so I don't know (and don't particularly want to learn) its complicated Unicode options and calls. Second, /[Ss\x{DF}]/u is hard to read. If I want the S letters of traditional German, I'll write them in the obvious way, as [Ssß]. No doubt Perl will let me do this somehow - but it is telling that none of your examples do it in such a straightforward way. > $ echo 'Ævar' | perl -ne 'utf8::decode($_); print $_ if /[Ss\x{DF}]/u' > $ echo 'baß' | perl -MEncode -ne 'utf8::decode($_); print > encode_utf8($_) if /[Ss\x{DF}]/u' > baß > $ echo 'Ævar' | perl -MEncode -ne 'utf8::decode($_); print > encode_utf8($_) if /[Ss\x{C6}]/u' > Ævar > $ echo 'Ævar' | perl -MEncode -ne 'utf8::decode($_); print > encode_utf8($_) if /[Ss\x{e6}]/ui' > Ævar ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-04 19:31 ` Junio C Hamano 2023-04-05 18:32 ` Paul Eggert @ 2023-04-06 13:39 ` demerphq 2023-04-07 19:00 ` Paul Eggert 1 sibling, 1 reply; 36+ messages in thread From: demerphq @ 2023-04-06 13:39 UTC (permalink / raw) To: Junio C Hamano Cc: Paul Eggert, Carlo Arenas, 60690, mega lith01, Ævar Arnfjörð Bjarmason, git, Tukusej’s Sirs, pcre-dev On Tue, 4 Apr 2023 at 21:31, Junio C Hamano <gitster@pobox.com> wrote: > > Paul Eggert <eggert@cs.ucla.edu> writes: > > > This is an evolving area. Git master is fiddling with flags and > > options, and so is GNU grep master, and so is PCRE2, and there are > > bugs. If you're running bleeding-edge versions of this code you'll get > > different behavior than if you're running grep 3.8, pcregrep 8.45, > > Perl 5.36, and git 2.39.2 (which is what Fedora 37 has). > > > > What I'm fearing is that we may evolve into mutually incompatible > > interpretations of how Perl regular expressions deal with UTF-8 > > text. That'd be a recipe for confusion down the road. > > Nicely said. My personal inclination is to let Perl folks decide > and follow them (even though I am skeptical about the wisdom of > letting '\d' match anything other than [0-9]), but even in Git > circle there would be different opinions, so I am glad that the > discussion is visible on the list to those who are intrested. Perl matches Unicode text according to the rules specified by the Unicode consortium. It is the reference implementation for Unicode regular expression matching. Unicode specifies that \d match any digit in any script that it supports. Thus \d matches far more codepoints than \p{PosixDigit} or [0-9] would. Be aware that Unicode contains and separates numbers and digits, eg, \x{1EC9E} represents a Lakh, which is used in many Indian languages for 100,000, but which is not considered a *digit* for obvious reasons. FWIW, someone mentioned [[:digit:]] which matches the same as \d does on Unicode strings and under the /u matching flag for regexes in Perl. Arguably this was a mistake, [[:digit:]] is a POSIX character class, and POSIX doesn't support Unicode so it should have matched [0-9] or \p{PosixDigit}. But historically \d and [[:digit:]] in Perl were the same and when \d was extended to meet the Unicode specification [[:digit:]] came along for the ride likely inadvertently, thus \p{PosixDigit} is equivalent to [0-9], but \p{XPosixDigit} is equivalent to \d and [[:digit:]]. I notice that other posts in this thread have moved the conversation on, and covered most of the points I wanted to make here. However I wanted to say that there seem to be two different issues here. The first is "what semantics do i expect from my regular expressions", Unicode or legacy-ASCII, mostly this relates to case-insensitive matching, but things like \d also surface discrepancies. The second is "what encodings does the regular expression engine understand". Unfortunately on *nix there is no tradition of using BOM's to distinguish the 6 different possible encodings of Unicode (UTF-8, UTF-EBCDIC, UTF-16LE, UTF-16BE, UTF-32LE, UTF-32BE), and there seems to be some level of desire of matching with unicode semantics against files that are not uniformly encoded in one of these formats. So the question comes up, A) how do you tell the regular expression engine what semantics you want and B) how does the regular expression library identify the encoding in the file, and how does it handle malformed content in that file. For instance if I have a file which contains snippets of UTF8 encoded data, *and* snippets of data that is illegal in UTF8, what should the regular expression engine do if it is asked to do a case insensitive match against that file. cheers, yves ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-06 13:39 ` demerphq @ 2023-04-07 19:00 ` Paul Eggert 2023-04-08 5:01 ` Carlo Arenas 0 siblings, 1 reply; 36+ messages in thread From: Paul Eggert @ 2023-04-07 19:00 UTC (permalink / raw) To: demerphq Cc: 60690, mega lith01, Carlo Arenas, Ævar Arnfjörð Bjarmason, Tukusej’s Sirs, git, pcre2-dev, Junio C Hamano On 2023-04-06 06:39, demerphq wrote: > Unicode specifies that \d match any digit > in any script that it supports. "Specifies" is too strong. The Unicode Regular Expressions technical standard (UTS#18) mentions \d only in Annex C[1], next to the word "digit" in a column labeled "Property" (even though \d is really syntax not a property). This is at best an informal recommendation, not a requirement, as UTS#18 0.2[2] says that UTS#18's syntax is only for illustration and that although it's similar to Perl's, the two syntax forms may not be exactly the same. So we can't look to UTS#18 for a definitive way out of the \d mess, as the Unicode folks specifically delegated matters to us. Even ignoring the \d issue the digit situation is messy. UTS#18 Annex C says "\p{gc=Decimal_Number}" is the standard recommended syntax assignment for digits. However, PCRE2 does not support this syntax; it supports another variant \p{Nd} that UTS#18 also recommends. So it appears that PCRE2 already does not implement every recommended aspect of UTS#18 syntax. PCRE2 also doesn't match Perl, which does support "\p{gc=Decimal_Number}". Anyway, since grep -P '\p{Nd}' implements Unicode's decimal digit class, that's clearly enough for grep -P to conform to UTS#18 with respect to digits. > A) how do you tell the regular expression > engine what semantics you want and B) how does the regular expression > library identify the encoding in the file, and how does it handle > malformed content in that file. Here's how GNU grep does it: * RE semantics are specified via command-line options like -P. * Text encoding is specified by locale, e.g., LC_ALL='en_US.utf8'. * REs do not match encoding errors. > on *nix there is no tradition of using BOM's to > distinguish the 6 different possible encodings of Unicode (UTF-8, > UTF-EBCDIC, UTF-16LE, UTF-16BE, UTF-32LE, UTF-32BE) Yes, GNU/Linux never really experienced the joys of UTF-EBCDIC, Oracle UTFE, UTF-16LE vs UTF-16BE etc. If you're running legacy IBM mainframe or MS-Windows code these legacy encodings are obviously a big deal. However, there seems little reason to force their nontrivial hassles onto every GNU/Linux program that processes text. A few specialized apps like 'iconv' deal with offbeat encodings, and that is probably a better approach all around. > there seems > to be some level of desire of matching with unicode semantics against > files that are not uniformly encoded in one of these formats. That is a use case, yes. It's what 'strings' and 'grep' do. [1]: https://unicode.org/reports/tr18/#Compatibility_Properties [2]: https://unicode.org/reports/tr18/#Conformance ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-07 19:00 ` Paul Eggert @ 2023-04-08 5:01 ` Carlo Arenas 2023-04-08 22:45 ` Paul Eggert 0 siblings, 1 reply; 36+ messages in thread From: Carlo Arenas @ 2023-04-08 5:01 UTC (permalink / raw) To: Paul Eggert Cc: demerphq, 60690, mega lith01, Ævar Arnfjörð Bjarmason, Tukusej’s Sirs, git, pcre2-dev, Junio C Hamano On Fri, Apr 7, 2023 at 12:00 PM Paul Eggert <eggert@cs.ucla.edu> wrote: > > On 2023-04-06 06:39, demerphq wrote: > > > Unicode specifies that \d match any digit > > in any script that it supports. > > "Specifies" is too strong. The Unicode Regular Expressions technical > standard (UTS#18) mentions \d only in Annex C[1], next to the word > "digit" in a column labeled "Property" (even though \d is really syntax > not a property). This is at best an informal recommendation, not a > requirement, as UTS#18 0.2[2] says that UTS#18's syntax is only for > illustration and that although it's similar to Perl's, the two syntax > forms may not be exactly the same. So we can't look to UTS#18 for a > definitive way out of the \d mess, as the Unicode folks specifically > delegated matters to us. > > Even ignoring the \d issue the digit situation is messy. UTS#18 Annex C > says "\p{gc=Decimal_Number}" is the standard recommended syntax > assignment for digits. However, PCRE2 does not support this syntax; it > supports another variant \p{Nd} that UTS#18 also recommends. So it > appears that PCRE2 already does not implement every recommended aspect > of UTS#18 syntax. PCRE2 also doesn't match Perl, which does support > "\p{gc=Decimal_Number}". Not sure I follow the whole logic here, but PCRE2[3] (search for "general category" which is what the "gc" above stands for) only supports the abbreviated form of the unicode classes and `Nd` is indeed the one that corresponds to `Decimal_Number`. Carlo [1]: https://unicode.org/reports/tr18/#Compatibility_Properties [2]: https://unicode.org/reports/tr18/#Conformance [3]: https://pcre2project.github.io/pcre2/doc/html/pcre2pattern.html ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: bug#60690: -P '\d' in GNU and git grep 2023-04-08 5:01 ` Carlo Arenas @ 2023-04-08 22:45 ` Paul Eggert 0 siblings, 0 replies; 36+ messages in thread From: Paul Eggert @ 2023-04-08 22:45 UTC (permalink / raw) To: Carlo Arenas Cc: demerphq, pcre2-dev, 60690, mega lith01, Ævar Arnfjörð Bjarmason, Junio C Hamano, Tukusej’s Sirs, git On 2023-04-07 22:01, Carlo Arenas wrote: > Not sure I follow the whole logic here, but PCRE2[3] (search for > "general category" which is what the "gc" above stands for) only > supports the abbreviated form of the unicode classes and `Nd` is > indeed the one that corresponds to `Decimal_Number`. That's fine: all that UTS#18[1] requires is that PCRE2 provide syntax for a regular expression that matches the Decimal Number class. Which PCRE2 does, via \p{Nd}. The logic is that UTF#18 does not require that \d must behave like \p{Nd}, or even that \p{gc=Decimal_Number} must behave like \p{Nd}. It merely requires that there be some syntax for matching Decimal Number, and it says the choice of syntax is up to the implementer. This is why UTF#18 doesn't require that \d must also match non-ASCII digits (which is what I think Yves was saying). [1]: https://unicode.org/reports/tr18/ ^ permalink raw reply [flat|nested] 36+ messages in thread
* [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-08 15:52 ` [PATCH v2] " Carlo Marcelo Arenas Belón 2023-01-09 11:35 ` Ævar Arnfjörð Bjarmason @ 2023-01-17 10:51 ` Carlo Marcelo Arenas Belón 2023-01-17 12:38 ` Ævar Arnfjörð Bjarmason 1 sibling, 1 reply; 36+ messages in thread From: Carlo Marcelo Arenas Belón @ 2023-01-17 10:51 UTC (permalink / raw) To: git; +Cc: avarab, gitster, Carlo Marcelo Arenas Belón When UTF is enabled for a PCRE match, the PCRE2_UTF flag is used by the pcre2_compile() call, but that would only allow for the use of Unicode character properties when caseless is required but not to include the additional UTF characters for all other class matches. This would result in failed matches for expressions that rely on those properties, for ex: $ git grep -P '\bÆvar' Add a configuration that could be used to enable the PCRE2_UCP flag to correctly match those cases, when required. The use of this has an impact on performance that has been estimated to be significant. Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> --- Changes since v2: * make setting UCP and opt-in as suggested by Ævar * remove performance test and instead add a test Documentation/config/grep.txt | 6 ++++++ grep.c | 11 ++++++++++- grep.h | 1 + t/t7810-grep.sh | 13 +++++++++++++ 4 files changed, 30 insertions(+), 1 deletion(-) diff --git a/Documentation/config/grep.txt b/Documentation/config/grep.txt index e521f20390..8848db7311 100644 --- a/Documentation/config/grep.txt +++ b/Documentation/config/grep.txt @@ -26,3 +26,9 @@ grep.fullName:: grep.fallbackToNoIndex:: If set to true, fall back to git grep --no-index if git grep is executed outside of a git repository. Defaults to false. + +pcre.ucp:: + If set to true, will use all Unicode Character Properties when matching + `\w`, `\b`, `\d` or the POSIX classes (ex: `[:alnum:]`) and PCRE is used + as the underlying engine. If PCRE is not being used it is ignored. + Defaults to false diff --git a/grep.c b/grep.c index 06eed69493..ceafb8937d 100644 --- a/grep.c +++ b/grep.c @@ -102,6 +102,12 @@ int grep_config(const char *var, const char *value, void *cb) return config_error_nonbool(var); return color_parse(value, color); } + + if (!strcmp(var, "pcre.ucp")) { + opt->pcre_ucp = git_config_bool(var, value); + return 0; + } + return 0; } @@ -292,8 +298,11 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt } options |= PCRE2_CASELESS; } - if (!opt->ignore_locale && is_utf8_locale() && !literal) + if (!opt->ignore_locale && is_utf8_locale() && !literal) { options |= (PCRE2_UTF | PCRE2_MATCH_INVALID_UTF); + if (opt->pcre_ucp) + options |= PCRE2_UCP; + } #ifndef GIT_PCRE2_VERSION_10_36_OR_HIGHER /* Work around https://bugs.exim.org/show_bug.cgi?id=2642 fixed in 10.36 */ diff --git a/grep.h b/grep.h index 6075f997e6..082bd3a0c7 100644 --- a/grep.h +++ b/grep.h @@ -171,6 +171,7 @@ struct grep_opt { int file_break; int heading; int max_count; + int pcre_ucp; void *priv; void (*output)(struct grep_opt *opt, const void *data, size_t size); diff --git a/t/t7810-grep.sh b/t/t7810-grep.sh index 8eded6ab27..a99a967060 100755 --- a/t/t7810-grep.sh +++ b/t/t7810-grep.sh @@ -95,6 +95,7 @@ test_expect_success setup ' then echo "¿" >reverse-question-mark fi && + echo "émotion" >ucp && git add . && test_tick && git commit -m initial @@ -1474,6 +1475,18 @@ test_expect_success PCRE 'grep -P backreferences work (the PCRE NO_AUTO_CAPTURE test_cmp hello_world actual ' +test_expect_success PCRE 'grep -c pcre.ucp -P fixes \b' ' + cat >expected <<-\EOF && + ucp:émotion + EOF + cat >pattern <<-\EOF && + \bémotion + EOF + LC_ALL=en_US.UTF-8 git -c pcre.ucp=true grep -P -f pattern >actual && + test_cmp expected actual && + LC_ALL=en_US.UTF-8 test_must_fail git grep -P -f pattern +' + test_expect_success 'grep -G invalidpattern properly dies ' ' test_must_fail git grep -G "a[" ' -- 2.37.1 (Apple Git-137.1) ^ permalink raw reply related [flat|nested] 36+ messages in thread
* Re: [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-17 10:51 ` [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P Carlo Marcelo Arenas Belón @ 2023-01-17 12:38 ` Ævar Arnfjörð Bjarmason 2023-01-17 15:19 ` Junio C Hamano 0 siblings, 1 reply; 36+ messages in thread From: Ævar Arnfjörð Bjarmason @ 2023-01-17 12:38 UTC (permalink / raw) To: Carlo Marcelo Arenas Belón; +Cc: git, gitster, Diomidis Spinellis On Tue, Jan 17 2023, Carlo Marcelo Arenas Belón wrote: > When UTF is enabled for a PCRE match, the PCRE2_UTF flag is used > by the pcre2_compile() call, but that would only allow for the > use of Unicode character properties when caseless is required > but not to include the additional UTF characters for all other > class matches. > > This would result in failed matches for expressions that rely > on those properties, for ex: > > $ git grep -P '\bÆvar' > > Add a configuration that could be used to enable the PCRE2_UCP > flag to correctly match those cases, when required. > > The use of this has an impact on performance that has been estimated > to be significant. > > Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> > --- > Changes since v2: > * make setting UCP and opt-in as suggested by Ævar To argue with myself here, I'm not so sure that just making this the default isn't the right move, especially as the GNU grep maintainer seems to be convinced that that's the right thing for grep(1). We've usually just followed GNU grep semantics, so if it's doing X and we're doing Y after this it's probably better to unify our behavior with theirs. I was mainly concerned with the behavior change sneaking in as a mere bugfix, I think it's OK if we change the behavior, as long as we're going into it with our eyes open... > * remove performance test and instead add a test ...I didn't follow the thread(s) where this may have been discussed, but I for one would like to see a perf test with this, but maybe it was removed for a good reason that I'm not aware of... > Documentation/config/grep.txt | 6 ++++++ > grep.c | 11 ++++++++++- > grep.h | 1 + > t/t7810-grep.sh | 13 +++++++++++++ > 4 files changed, 30 insertions(+), 1 deletion(-) > > diff --git a/Documentation/config/grep.txt b/Documentation/config/grep.txt > index e521f20390..8848db7311 100644 > --- a/Documentation/config/grep.txt > +++ b/Documentation/config/grep.txt > @@ -26,3 +26,9 @@ grep.fullName:: > grep.fallbackToNoIndex:: > If set to true, fall back to git grep --no-index if git grep > is executed outside of a git repository. Defaults to false. > + > +pcre.ucp:: > + If set to true, will use all Unicode Character Properties when matching > + `\w`, `\b`, `\d` or the POSIX classes (ex: `[:alnum:]`) and PCRE is used > + as the underlying engine. If PCRE is not being used it is ignored. > + Defaults to false There's a couple of exceptions to this, but we tend to stick config docs in their corresponding Documentation/config/<namespace>.txt, so this should be in a new Documentation/config/pcre.txt if we're adding this name. But I'd rather that we don't expose the implementation detail that we're using PCRE, which we haven't done so far. We just have a "grep.patternType=perl", which (and that's another issue, in any case) we should explicitly mention here, i.e. that this is for use with that config (and corresponding option(s)). I think calling this e.g.: grep.perl.Unicode=<bool> grep.patternTypePerl.Unicode=<bool> Or even: grep.patternTypePerl.Flags=u Would be better, i.e. PCRE's C API is really just mapping to the flags you can find in "perldoc perlre" (https://perldoc.perl.org/perlre). In this case the /u flag maps to the "PCRE2_UCP" API flag. That we happen to use PCRE to give ourselves "Perl" semantics is an implementation detail we should avoid exposing, so we could either give our config generic names, or literally map to the perl /flags/. For now we could just die on any "Flags" value that isn't "u". Of course all of this is predicated on us wanting to leave this as an opt-in, which I'm not so sure about. If it's opt-out we'll avoid this entire question, > diff --git a/grep.c b/grep.c > index 06eed69493..ceafb8937d 100644 > --- a/grep.c > +++ b/grep.c > @@ -102,6 +102,12 @@ int grep_config(const char *var, const char *value, void *cb) > return config_error_nonbool(var); > return color_parse(value, color); > } > + > + if (!strcmp(var, "pcre.ucp")) { > + opt->pcre_ucp = git_config_bool(var, value); > + return 0; > + } > + > return 0; > } > > @@ -292,8 +298,11 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt > } > options |= PCRE2_CASELESS; > } > - if (!opt->ignore_locale && is_utf8_locale() && !literal) > + if (!opt->ignore_locale && is_utf8_locale() && !literal) { > options |= (PCRE2_UTF | PCRE2_MATCH_INVALID_UTF); > + if (opt->pcre_ucp) > + options |= PCRE2_UCP; > + } This interaction with locale settings etc. is probably correct, but if we're keeping the config etc. we should really document how this interacts with those. I.e. you might expect "-c grep.patternType=perl -c <whatever_the_setting_is>=true" to give you UCP semantics, but we'll ignore it based on these other criteria. > #ifndef GIT_PCRE2_VERSION_10_36_OR_HIGHER > /* Work around https://bugs.exim.org/show_bug.cgi?id=2642 fixed in 10.36 */ > diff --git a/grep.h b/grep.h > index 6075f997e6..082bd3a0c7 100644 > --- a/grep.h > +++ b/grep.h > @@ -171,6 +171,7 @@ struct grep_opt { > int file_break; > int heading; > int max_count; > + int pcre_ucp; > void *priv; The reason for why we have some "bool"-like settings (like "int ignore_case") as an "int" as opposed to an "unsigned int <name>:1" bitfield is because we need to take their address via the parse_options() API. But in this case it's a purely internal field, so (and again, if we're keeping the option) let's use "unsigned int ...:1" here instead? Unless that is, we're expecting a corresponding command-line option. > > void (*output)(struct grep_opt *opt, const void *data, size_t size); > diff --git a/t/t7810-grep.sh b/t/t7810-grep.sh > index 8eded6ab27..a99a967060 100755 > --- a/t/t7810-grep.sh > +++ b/t/t7810-grep.sh > @@ -95,6 +95,7 @@ test_expect_success setup ' > then > echo "¿" >reverse-question-mark > fi && > + echo "émotion" >ucp && Here we carry this file through the entirety ouf our tests... > git add . && > test_tick && > git commit -m initial > @@ -1474,6 +1475,18 @@ test_expect_success PCRE 'grep -P backreferences work (the PCRE NO_AUTO_CAPTURE > test_cmp hello_world actual > ' > > +test_expect_success PCRE 'grep -c pcre.ucp -P fixes \b' ' > + cat >expected <<-\EOF && > + ucp:émotion ...only to use it in this one test, it clearly didn't harm anything (or rather, I didn't run this, but I expect you did and it passed), but how about avoiding more global state here doing: test_when_finished "rm -rf repo" && git init repo && test_commit -C repo msg ucp émotion && [...] > + EOF > + cat >pattern <<-\EOF && > + \bémotion > + EOF > + LC_ALL=en_US.UTF-8 git -c pcre.ucp=true grep -P -f pattern >actual && > + test_cmp expected actual && > + LC_ALL=en_US.UTF-8 test_must_fail git grep -P -f pattern This will break on platforms that don't have en_US.UTF-8 (and that's not hypothetical, some systems will skip installing locales for various reasons). I see we have some almost recent breakage 1819ad327b7 (grep: fix multibyte regex handling under macOS, 2022-08-26), but that one adds a new MB_REGEX prereq, which presumably fails if we don't have this locale. You can just use the existing "GETTEXT_LOCALE", which will piggy-back on our existing locale tests, or we could add a corresponding one for en_US.UTF-8 and refactor the existing MB_REGEX to be in lib-gettext.sh where it arguably belongs... > +' > + > test_expect_success 'grep -G invalidpattern properly dies ' ' > test_must_fail git grep -G "a[" > ' ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-17 12:38 ` Ævar Arnfjörð Bjarmason @ 2023-01-17 15:19 ` Junio C Hamano 2023-01-18 7:35 ` Carlo Arenas 0 siblings, 1 reply; 36+ messages in thread From: Junio C Hamano @ 2023-01-17 15:19 UTC (permalink / raw) To: Ævar Arnfjörð Bjarmason Cc: Carlo Marcelo Arenas Belón, git, Diomidis Spinellis Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes: > To argue with myself here, I'm not so sure that just making this the > default isn't the right move, especially as the GNU grep maintainer > seems to be convinced that that's the right thing for grep(1). OK. > I think calling this e.g.: > > grep.perl.Unicode=<bool> > grep.patternTypePerl.Unicode=<bool> > > Or even: > > grep.patternTypePerl.Flags=u > > Would be better, i.e. PCRE's C API is really just mapping to the flags > you can find in "perldoc perlre" (https://perldoc.perl.org/perlre). In > this case the /u flag maps to the "PCRE2_UCP" API flag. > > That we happen to use PCRE to give ourselves "Perl" semantics is an > implementation detail we should avoid exposing, so we could either give > our config generic names, or literally map to the perl /flags/. > > For now we could just die on any "Flags" value that isn't "u". > > Of course all of this is predicated on us wanting to leave this as an > opt-in, which I'm not so sure about. If it's opt-out we'll avoid this > entire question, Making it opt-out would also require a similar knob to turn the "flag" off, be it a configuration variable or a command line option, wouldn't it? I tend to agree with you that it makes sense to make it a goal to take us closer to "grep -P" from GNU---do they have such an opt-out knob? If not, let's make it simple by turning it always on, which would be the simplest ;-) Again, thanks for a careful review with concrete points. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-17 15:19 ` Junio C Hamano @ 2023-01-18 7:35 ` Carlo Arenas 2023-01-18 11:49 ` Ævar Arnfjörð Bjarmason 0 siblings, 1 reply; 36+ messages in thread From: Carlo Arenas @ 2023-01-18 7:35 UTC (permalink / raw) To: Junio C Hamano Cc: Ævar Arnfjörð Bjarmason, git, Diomidis Spinellis On Tue, Jan 17, 2023 at 7:19 AM Junio C Hamano <gitster@pobox.com> wrote: > > Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes: > > > To argue with myself here, I'm not so sure that just making this the > > default isn't the right move, especially as the GNU grep maintainer > > seems to be convinced that that's the right thing for grep(1). > > OK. I think that is definitely the right thing to do for grep, because the current behaviour can only be described as a bug (and a bad one at it), but after all the push back and performance testing, I am also not convinced anymore it needs to be the default for git, because the negatives outweigh the positives. First there is the performance hit, which is inevitable because there are just a lot more characters to match when UCP tables are being used, and second there is the fact that PCRE2_UCP itself might not be what you want when matching code, because for example numbers are never going to be using digits outside what ASCII provides, and identifiers have a narrow set of characters as valid than what you would expect from all written human languages in history. Lastly, even with PCRE2_UCP enabled, our current logic for word matches is still broken, because the current code still uses a definition of word that was done outside what the regex engines provide and that roughly matches what you would expect of identifiers from C in the ASCII times. > > Of course all of this is predicated on us wanting to leave this as an > > opt-in, which I'm not so sure about. If it's opt-out we'll avoid this > > entire question, > > Making it opt-out would also require a similar knob to turn the > "flag" off, be it a configuration variable or a command line option, > wouldn't it? I tend to agree with you that it makes sense to make > it a goal to take us closer to "grep -P" from GNU---do they have > such an opt-out knob? If not, let's make it simple by turning it > always on, which would be the simplest ;-) GNU grep -P has no knob and would likely never have one. So for now, I think we should acknowledge the bug, provide an option for people that might need the fix, and fix all other problems we have, which will include changes in PCRE2 as well to better fit our use case. Carlo ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-18 7:35 ` Carlo Arenas @ 2023-01-18 11:49 ` Ævar Arnfjörð Bjarmason 2023-01-18 16:20 ` Junio C Hamano 0 siblings, 1 reply; 36+ messages in thread From: Ævar Arnfjörð Bjarmason @ 2023-01-18 11:49 UTC (permalink / raw) To: Carlo Arenas; +Cc: Junio C Hamano, git, Diomidis Spinellis On Tue, Jan 17 2023, Carlo Arenas wrote: > On Tue, Jan 17, 2023 at 7:19 AM Junio C Hamano <gitster@pobox.com> wrote: >> >> Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes: >> >> > To argue with myself here, I'm not so sure that just making this the >> > default isn't the right move, especially as the GNU grep maintainer >> > seems to be convinced that that's the right thing for grep(1). >> >> OK. > > I think that is definitely the right thing to do for grep, because the > current behaviour can only be described as a bug (and a bad one at > it), but after all the push back and performance testing, I am also > not convinced anymore it needs to be the default for git, because the > negatives outweigh the positives. > > First there is the performance hit, which is inevitable because there > are just a lot more characters to match when UCP tables are being > used,[...] I'm less concerned about the performance, we should aim for correctness first. We can always provide an opt-out (and the locale setting is already that opt-out). > and second there is the fact that PCRE2_UCP itself might not be > what you want when matching code, because for example numbers are > never going to be using digits outside what ASCII provides, and > identifiers have a narrow set of characters as valid than what you > would expect from all written human languages in history. [0-9] will be ASCII, but \d will use [^0-9] Unicode numbers. I agree it might not be expected by some, but I can't really square that view in my mind with the desire to match "\bÆvar" :). After all that "Æ" is also arbitrary byte garbage in the ASCII-view of the world. I can see how it might be more practical in some cases to have "\b" have Unicode semantics, but to specifically make "\d" an exception. But the ship has sailed on that in Perl & PCRE land years (or more than a decade ago). I think us coming up with some exception to that would probably suck more than going with their behavior. > Lastly, even with PCRE2_UCP enabled, our current logic for word > matches is still broken, because the current code still uses a > definition of word that was done outside what the regex engines > provide and that roughly matches what you would expect of identifiers > from C in the ASCII times. Yes, FWIW I have some WIP patches somewhere to get rid of that bit of grep.c if we're using PCRE. I.e. the "-w" should be powered by just adding "\b" to the start/end of the provided string. That'll then be correct, and faster. I can't remember if there were some subtle bugs in that, or why I didn't finish that... >> > Of course all of this is predicated on us wanting to leave this as an >> > opt-in, which I'm not so sure about. If it's opt-out we'll avoid this >> > entire question, >> >> Making it opt-out would also require a similar knob to turn the >> "flag" off, be it a configuration variable or a command line option, >> wouldn't it? I tend to agree with you that it makes sense to make >> it a goal to take us closer to "grep -P" from GNU---do they have >> such an opt-out knob? If not, let's make it simple by turning it >> always on, which would be the simplest ;-) > > GNU grep -P has no knob and would likely never have one. I think the general knob in not just GNU grep but GNU utils and the wider *nix landscape is "tweak your LC_ALL and/or other locale varibales". Which works for it, and will work for us once we're using PCRE2_UCP too. > So for now, I think we should acknowledge the bug, provide an option > for people that might need the fix, and fix all other problems we > have, which will include changes in PCRE2 as well to better fit our > use case. Hrm, what are those PCRE2 changes? The one I saw so far (or was it a proposal) was to just make its "grep" utility use the PCRE2_UCP like GNU grep is now doing in its unreleased version in its git repo... ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-18 11:49 ` Ævar Arnfjörð Bjarmason @ 2023-01-18 16:20 ` Junio C Hamano 2023-01-18 23:06 ` Ævar Arnfjörð Bjarmason 0 siblings, 1 reply; 36+ messages in thread From: Junio C Hamano @ 2023-01-18 16:20 UTC (permalink / raw) To: Ævar Arnfjörð Bjarmason Cc: Carlo Arenas, git, Diomidis Spinellis Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes: >> GNU grep -P has no knob and would likely never have one. > > I think the general knob in not just GNU grep but GNU utils and the > wider *nix landscape is "tweak your LC_ALL and/or other locale > varibales". > > Which works for it, and will work for us once we're using PCRE2_UCP too. > >> So for now, I think we should acknowledge the bug, provide an option >> for people that might need the fix, and fix all other problems we >> have, which will include changes in PCRE2 as well to better fit our >> use case. > > Hrm, what are those PCRE2 changes? The one I saw so far (or was it a > proposal) was to just make its "grep" utility use the PCRE2_UCP like GNU > grep is now doing in its unreleased version in its git repo... Yeah, I didn't understand Carlo's comment in that paragraph at all. In short, it sounds to me that the earlier one that added PCRE2_UCP unconditionally would be the best alternative among those that have been discussed. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-18 16:20 ` Junio C Hamano @ 2023-01-18 23:06 ` Ævar Arnfjörð Bjarmason 2023-01-18 23:24 ` Junio C Hamano 0 siblings, 1 reply; 36+ messages in thread From: Ævar Arnfjörð Bjarmason @ 2023-01-18 23:06 UTC (permalink / raw) To: Junio C Hamano; +Cc: Carlo Arenas, git, Diomidis Spinellis On Wed, Jan 18 2023, Junio C Hamano wrote: > Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes: > >>> GNU grep -P has no knob and would likely never have one. >> >> I think the general knob in not just GNU grep but GNU utils and the >> wider *nix landscape is "tweak your LC_ALL and/or other locale >> varibales". >> >> Which works for it, and will work for us once we're using PCRE2_UCP too. >> >>> So for now, I think we should acknowledge the bug, provide an option >>> for people that might need the fix, and fix all other problems we >>> have, which will include changes in PCRE2 as well to better fit our >>> use case. >> >> Hrm, what are those PCRE2 changes? The one I saw so far (or was it a >> proposal) was to just make its "grep" utility use the PCRE2_UCP like GNU >> grep is now doing in its unreleased version in its git repo... > > Yeah, I didn't understand Carlo's comment in that paragraph at all. > > In short, it sounds to me that the earlier one that added PCRE2_UCP > unconditionally would be the best alternative among those that have > been discussed. I agree. ^ permalink raw reply [flat|nested] 36+ messages in thread
* Re: [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P 2023-01-18 23:06 ` Ævar Arnfjörð Bjarmason @ 2023-01-18 23:24 ` Junio C Hamano 0 siblings, 0 replies; 36+ messages in thread From: Junio C Hamano @ 2023-01-18 23:24 UTC (permalink / raw) To: Ævar Arnfjörð Bjarmason Cc: Carlo Arenas, git, Diomidis Spinellis Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes: >> In short, it sounds to me that the earlier one that added PCRE2_UCP >> unconditionally would be the best alternative among those that have >> been discussed. > > I agree. So, ... we'll mark cb/grep-pcre-ucp, ea8bc435 (grep: correctly identify utf-8 characters with \{b,w} in -P, 2023-01-08), to be merged to 'next' and see what happens. I'll add your Acked-by while at it, if you do not mind. ---- >8 --------- >8 --------- >8 --------- >8 ------ From: Carlo Marcelo Arenas Belón <carenas@gmail.com> Date: Sun, 8 Jan 2023 07:52:17 -0800 Subject: [PATCH] grep: correctly identify utf-8 characters with \{b,w} in -P When UTF is enabled for a PCRE match, the corresponding flags are added to the pcre2_compile() call, but PCRE2_UCP wasn't included. This prevents extending the meaning of the character classes to include those new valid characters and therefore result in failed matches for expressions that rely on that extention, for ex: $ git grep -P '\bÆvar' Add PCRE2_UCP so that \w will include Æ and therefore \b could correctly match the beginning of that word. This has an impact on performance that has been estimated to be between 20% to 40% and that is shown through the added performance test. Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com> Acked-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com> --- grep.c | 2 +- t/perf/p7822-grep-perl-character.sh | 42 +++++++++++++++++++++++++++++ 2 files changed, 43 insertions(+), 1 deletion(-) create mode 100755 t/perf/p7822-grep-perl-character.sh diff --git a/grep.c b/grep.c index 06eed69493..1687f65b64 100644 --- a/grep.c +++ b/grep.c @@ -293,7 +293,7 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt options |= PCRE2_CASELESS; } if (!opt->ignore_locale && is_utf8_locale() && !literal) - options |= (PCRE2_UTF | PCRE2_MATCH_INVALID_UTF); + options |= (PCRE2_UTF | PCRE2_UCP | PCRE2_MATCH_INVALID_UTF); #ifndef GIT_PCRE2_VERSION_10_36_OR_HIGHER /* Work around https://bugs.exim.org/show_bug.cgi?id=2642 fixed in 10.36 */ diff --git a/t/perf/p7822-grep-perl-character.sh b/t/perf/p7822-grep-perl-character.sh new file mode 100755 index 0000000000..87009c60df --- /dev/null +++ b/t/perf/p7822-grep-perl-character.sh @@ -0,0 +1,42 @@ +#!/bin/sh + +test_description="git-grep's perl regex + +If GIT_PERF_GREP_THREADS is set to a list of threads (e.g. '1 4 8' +etc.) we will test the patterns under those numbers of threads. +" + +. ./perf-lib.sh + +test_perf_large_repo +test_checkout_worktree + +if test -n "$GIT_PERF_GREP_THREADS" +then + test_set_prereq PERF_GREP_ENGINES_THREADS +fi + +for pattern in \ + '\\bhow' \ + '\\bÆvar' \ + '\\d+ \\bÆvar' \ + '\\bBelón\\b' \ + '\\w{12}\\b' +do + echo '$pattern' >pat + if ! test_have_prereq PERF_GREP_ENGINES_THREADS + then + test_perf "grep -P '$pattern'" --prereq PCRE " + git -P grep -f pat || : + " + else + for threads in $GIT_PERF_GREP_THREADS + do + test_perf "grep -P '$pattern' with $threads threads" --prereq PTHREADS,PCRE " + git -c grep.threads=$threads -P grep -f pat || : + " + done + fi +done + +test_done -- 2.39.1-231-ga7caae2729 ^ permalink raw reply related [flat|nested] 36+ messages in thread
end of thread, other threads:[~2023-04-08 22:45 UTC | newest] Thread overview: 36+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2023-01-08 6:23 [PATCH] grep: correctly identify utf-8 characters with \{b,w} in -P Carlo Marcelo Arenas Belón 2023-01-08 6:39 ` Junio C Hamano 2023-01-08 15:52 ` [PATCH v2] " Carlo Marcelo Arenas Belón 2023-01-09 11:35 ` Ævar Arnfjörð Bjarmason 2023-01-09 18:40 ` bug#60690: [PATCH v2] grep: correctly identify utf-8 characters with \{b, w} " Paul Eggert 2023-01-09 19:51 ` Ævar Arnfjörð Bjarmason 2023-01-09 23:12 ` Paul Eggert 2023-01-10 4:49 ` [PATCH v2] grep: correctly identify utf-8 characters with \{b,w} " Carlo Arenas 2023-01-16 20:48 ` Junio C Hamano 2023-04-03 21:38 ` -P '\d' in GNU and git grep Paul Eggert 2023-04-04 3:30 ` bug#60690: " Jim Meyering 2023-04-04 6:46 ` Paul Eggert 2023-04-04 15:31 ` Jim Meyering 2023-04-04 6:56 ` Carlo Arenas 2023-04-04 18:25 ` bug#60690: " Paul Eggert 2023-04-04 19:31 ` Junio C Hamano 2023-04-05 18:32 ` Paul Eggert 2023-04-05 19:04 ` Paul Eggert 2023-04-05 19:37 ` Junio C Hamano 2023-04-05 19:40 ` Jim Meyering 2023-04-05 20:03 ` Paul Eggert 2023-04-05 21:20 ` Carlo Arenas 2023-04-06 15:45 ` demerphq 2023-04-07 16:48 ` Paul Eggert 2023-04-06 13:39 ` demerphq 2023-04-07 19:00 ` Paul Eggert 2023-04-08 5:01 ` Carlo Arenas 2023-04-08 22:45 ` Paul Eggert 2023-01-17 10:51 ` [PATCH v3] grep: correctly identify utf-8 characters with \{b,w} in -P Carlo Marcelo Arenas Belón 2023-01-17 12:38 ` Ævar Arnfjörð Bjarmason 2023-01-17 15:19 ` Junio C Hamano 2023-01-18 7:35 ` Carlo Arenas 2023-01-18 11:49 ` Ævar Arnfjörð Bjarmason 2023-01-18 16:20 ` Junio C Hamano 2023-01-18 23:06 ` Ævar Arnfjörð Bjarmason 2023-01-18 23:24 ` Junio C Hamano
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