git-grep: Update tests (mainly for -P)

Add few more tests for "-P/--perl-regexp" option of "git grep".

While at it, add some generic tests for grep.extendedRegexp config option,
for detecting invalid regexep and check if "last one wins" rule works for
selecting regexp type.

Signed-off-by: Michał Kiedrowicz <michal.kiedrowicz@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t7810-grep.sh

@@ -32,6 +32,11 @@ test_expect_success setup '
 		echo Hello_world
 		echo HeLLo_world
 	} >hello_world &&
+	{
+		echo aab
+		echo a+b
+		echo a\\+b
+	} >ab &&
 	echo vvv >v &&
 	echo ww w >w &&
 	echo x x xx x >x &&
@@ -227,7 +232,17 @@ do
 		git grep --max-depth 0 -n -e vvv $H -- t . >actual &&
 		test_cmp expected actual
 	'
+	test_expect_success "grep $L with grep.extendedRegexp=false" '
+		echo "ab:a+b" >expected &&
+		git -c grep.extendedRegexp=false grep "a+b" >actual &&
+		test_cmp expected actual
+	'
 
+	test_expect_success "grep $L with grep.extendedRegexp=true" '
+		echo "ab:aab" >expected &&
+		git -c grep.extendedRegexp=true grep "a+b" >actual &&
+		test_cmp expected actual
+	'
 done
 
 cat >expected <<EOF
@@ -620,6 +635,28 @@ test_expect_success LIBPCRE 'grep -P pattern' '
 	test_cmp expected actual
 '
 
+test_expect_success 'grep pattern with grep.extendedRegexp=true' '
+	:>empty &&
+	test_must_fail git -c grep.extendedregexp=true \
+		grep "\p{Ps}.*?\p{Pe}" hello.c >actual &&
+	test_cmp empty actual
+'
+
+test_expect_success LIBPCRE 'grep -P pattern with grep.extendedRegexp=true' '
+	git -c grep.extendedregexp=true \
+		grep -P "\p{Ps}.*?\p{Pe}" hello.c >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success LIBPCRE 'grep -P -v pattern' '
+	{
+		echo ab:a+b
+		echo ab:a\\+b
+	} >expected &&
+	git grep -P -v "aab" ab >actual &&
+	test_cmp expected actual
+'
+
 test_expect_success LIBPCRE 'grep -P -i pattern' '
 	{
 		echo "hello.c:	printf(\"Hello world.\n\");"
@@ -637,4 +674,52 @@ test_expect_success LIBPCRE 'grep -P -w pattern' '
 	test_cmp expected actual
 '
 
+test_expect_success 'grep -G invalidpattern properly dies ' '
+	test_must_fail git grep -G "a["
+'
+
+test_expect_success 'grep -E invalidpattern properly dies ' '
+	test_must_fail git grep -E "a["
+'
+
+test_expect_success LIBPCRE 'grep -P invalidpattern properly dies ' '
+	test_must_fail git grep -P "a["
+'
+
+test_expect_success 'grep -F -E -G pattern' '
+	echo ab:a+b >expected &&
+	git grep -F -E -G a+b >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'grep -F -G -E pattern' '
+	echo ab:aab >expected &&
+	git grep -F -G -E a+b >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'grep -E -F -G pattern' '
+	echo ab:aab >expected &&
+	git grep -E -F -G a\\+b >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'grep -E -G -F pattern' '
+	echo ab:a\\+b >expected &&
+	git grep -E -G -F a\\+b >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success 'grep -G -F -E pattern' '
+	echo ab:a+b >expected &&
+	git grep -G -F -E a\\+b >actual &&
+	test_cmp expected actual
+'
+
+test_expect_success LIBPCRE 'grep -E -G -F -P pattern' '
+	echo ab:a+b >expected &&
+	git grep -E -G -F -P a\\+b >actual &&
+	test_cmp expected actual
+'
+
 test_done