config API users: test for *_get_value_multi() segfaults

As we'll discuss in the subsequent commit these tests all
show *_get_value_multi() API users unable to handle there being a
value-less key in the config, which is represented with a "NULL" for
that entry in the "string" member of the returned "struct
string_list", causing a segfault.

These added tests exhaustively test for that issue, as we'll see in a
subsequent commit we'll need to change all of the API users
of *_get_value_multi(). These cases were discovered by triggering each
one individually, and then adding these tests.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/t/t7900-maintenance.sh b/t/t7900-maintenance.sh
index 823331e44a..d82eac6a47 100755
--- a/t/t7900-maintenance.sh
+++ b/t/t7900-maintenance.sh
@@ -524,6 +524,29 @@ test_expect_success 'register and unregister' '
 	git maintenance unregister --config-file ./other --force
 '
 
+test_expect_failure 'register with no value for maintenance.repo' '
+	cp .git/config .git/config.orig &&
+	test_when_finished mv .git/config.orig .git/config &&
+
+	cat >>.git/config <<-\EOF &&
+	[maintenance]
+		repo
+	EOF
+	git maintenance register
+'
+
+test_expect_failure 'unregister with no value for maintenance.repo' '
+	cp .git/config .git/config.orig &&
+	test_when_finished mv .git/config.orig .git/config &&
+
+	cat >>.git/config <<-\EOF &&
+	[maintenance]
+		repo
+	EOF
+	git maintenance unregister &&
+	git maintenance unregister --force
+'
+
 test_expect_success !MINGW 'register and unregister with regex metacharacters' '
 	META="a+b*c" &&
 	git init "$META" &&