Make t5710 more strict when creating nested repos

The test 'creating too deep nesting' can fail even when cloning the repos,
but is not its main purpose (it has to prepare nested repos and ensure
the last one is invalid). So split the test into the creation and
invalidity checking parts.

Signed-off-by: Alex Riesen <raa.lkml@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t5710-info-alternate.sh

@@ -53,14 +53,18 @@ git prune'
 
 cd "$base_dir"
 
-test_expect_failure 'creating too deep nesting' \
+test_expect_success 'creating too deep nesting' \
 'git clone -l -s C D &&
 git clone -l -s D E &&
 git clone -l -s E F &&
 git clone -l -s F G &&
-git clone -l -s G H &&
+git clone -l -s G H'
-cd H &&
+
-test_valid_repo'
+test_expect_success 'invalidity of deepest repository' \
+'cd H && {
+	test_valid_repo
+	test $? -ne 0
+}'
 
 cd "$base_dir"