[PATCH 5/8] log tests: check if grep_config() is called by "log"-like cmds

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

Extend the tests added in my 9df46763ef1 (log: add exhaustive tests
for pattern style options & config, 2017-05-20) to check not only
whether "git log" handles "grep.patternType", but also "git show"
etc.

It's sufficient to check whether a PCRE regex matches for the purposes
of this test, we otherwise assume that it's running the same code as
"git log", whose behavior is tested more exhaustively by test added in
9df46763ef1e.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 t/t4202-log.sh | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/t/t4202-log.sh b/t/t4202-log.sh
index 7884e3d46b3..a114c49ef27 100755
--- a/t/t4202-log.sh
+++ b/t/t4202-log.sh
@@ -449,6 +449,22 @@ test_expect_success !FAIL_PREREQS 'log with various grep.patternType configurati
 	)
 '
 
+for cmd in show whatchanged reflog format-patch
+do
+	myarg=
+	if test "$cmd" = "format-patch"
+	then
+		myarg="HEAD~.."
+	fi
+
+	test_expect_success PCRE "$cmd: understands grep.patternType=perl, like 'log'" '
+		git -c grep.patternType=fixed -C pattern-type $cmd --grep="1(?=\|2)" $myarg >actual &&
+		test_must_be_empty actual &&
+		git -c grep.patternType=perl -C pattern-type $cmd --grep="1(?=\|2)" $myarg >actual &&
+		test_file_not_empty actual
+	'
+done
+
 test_expect_success 'log --author' '
 	cat >expect <<-\EOF &&
 	Author: <BOLD;RED>A U<RESET> Thor <author@example.com>
-- 
2.34.0.rc1.741.gab7bfd97031