t7601 (merge-pull-config): add missing &&

Also prefix several relevant git merge commands with 'test_must_fail' to
keep the tests passing.

Acked-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t7601-merge-pull-config.sh

@@ -114,13 +114,13 @@ test_expect_success 'setup conflicted merge' '
 test_expect_success 'merge picks up the best result' '
 	git config --unset-all pull.twohead &&
 	git reset --hard c5 &&
-	git merge -s resolve c6
+	test_must_fail git merge -s resolve c6 &&
 	resolve_count=$(conflict_count) &&
 	git reset --hard c5 &&
-	git merge -s recursive c6
+	test_must_fail git merge -s recursive c6 &&
 	recursive_count=$(conflict_count) &&
 	git reset --hard c5 &&
-	git merge -s recursive -s resolve c6
+	test_must_fail git merge -s recursive -s resolve c6 &&
 	auto_count=$(conflict_count) &&
 	test $auto_count = $recursive_count &&
 	test $auto_count != $resolve_count
@@ -129,13 +129,13 @@ test_expect_success 'merge picks up the best result' '
 test_expect_success 'merge picks up the best result (from config)' '
 	git config pull.twohead "recursive resolve" &&
 	git reset --hard c5 &&
-	git merge -s resolve c6
+	test_must_fail git merge -s resolve c6 &&
 	resolve_count=$(conflict_count) &&
 	git reset --hard c5 &&
-	git merge -s recursive c6
+	test_must_fail git merge -s recursive c6 &&
 	recursive_count=$(conflict_count) &&
 	git reset --hard c5 &&
-	git merge c6
+	test_must_fail git merge c6 &&
 	auto_count=$(conflict_count) &&
 	test $auto_count = $recursive_count &&
 	test $auto_count != $resolve_count