[PATCH v4 3/8] log: add -P as a synonym for --perl-regexp

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

Add a short -P option as a synonym for the longer --perl-regexp, for
consistency with the options the corresponding grep invocations
accept.

This was intentionally omitted in commit 727b6fc3ed ("log --grep:
accept --basic-regexp and --perl-regexp", 2012-10-03) for unspecified
future use.

Make it consistent with "grep" rather than to keep it open for future
use, and to avoid the confusion of -P meaning different things for
grep & log, as is the case with the -G option.

As noted in the aforementioned commit the --basic-regexp option can't
have a corresponding -G argument, as the log command already uses that
for -G<regex>.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 Documentation/rev-list-options.txt |  1 +
 revision.c                         |  2 +-
 t/t4202-log.sh                     | 12 ++++++++++++
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index a46f70c2b1..9c44eae55d 100644
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt
@@ -91,6 +91,7 @@ endif::git-rev-list[]
 	Consider the limiting patterns to be fixed strings (don't interpret
 	pattern as a regular expression).
 
+-P::
 --perl-regexp::
 	Consider the limiting patterns to be Perl-compatible regular
 	expressions.
diff --git a/revision.c b/revision.c
index eb87dce316..14b598644c 100644
--- a/revision.c
+++ b/revision.c
@@ -1996,7 +1996,7 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 		DIFF_OPT_SET(&revs->diffopt, PICKAXE_IGNORE_CASE);
 	} else if (!strcmp(arg, "--fixed-strings") || !strcmp(arg, "-F")) {
 		revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_FIXED;
-	} else if (!strcmp(arg, "--perl-regexp")) {
+	} else if (!strcmp(arg, "--perl-regexp") || !strcmp(arg, "-P")) {
 		revs->grep_filter.pattern_type_option = GREP_PATTERN_TYPE_PCRE;
 	} else if (!strcmp(arg, "--all-match")) {
 		revs->grep_filter.all_match = 1;
diff --git a/t/t4202-log.sh b/t/t4202-log.sh
index 703da5a116..a4049ad678 100755
--- a/t/t4202-log.sh
+++ b/t/t4202-log.sh
@@ -404,8 +404,20 @@ test_expect_success 'log with various grep.patternType configurations & command-
 			--grep="(1|2)" >actual.fixed.short-arg &&
 		git log --pretty=tformat:%s -E \
 			--grep="\|2" >actual.extended.short-arg &&
+		if test_have_prereq PCRE
+		then
+			git log --pretty=tformat:%s -P \
+				--grep="[\d]\|" >actual.perl.short-arg
+		else
+			test_must_fail git log -P \
+				--grep="[\d]\|"
+		fi &&
 		test_cmp expect.fixed actual.fixed.short-arg &&
 		test_cmp expect.extended actual.extended.short-arg &&
+		if test_have_prereq PCRE
+		then
+			test_cmp expect.perl actual.perl.short-arg
+		fi &&
 
 		git log --pretty=tformat:%s --fixed-strings \
 			--grep="(1|2)" >actual.fixed.long-arg &&
-- 
2.13.0.303.g4ebf302169