diff --git a/tests/test_substitution.c b/tests/test_substitution.c
index c9ca3cfb5dac3b2e32f6e888ccebf653db78c285..0fa0a584ea8569fe4bb8085b1062019850d1e045 100644
--- a/tests/test_substitution.c
+++ b/tests/test_substitution.c
@@ -288,7 +288,7 @@ AST_TEST_DEFINE(test_substitution)
 	pbx_builtin_setvar_helper(c, "list1", "ab&cd&ef");
 	TEST(test_expected_result(test, c, "${LISTFILTER(list1,&,cd)}", "ab&ef"));
 	TEST(test_expected_result(test, c, "${SHELL(printf '%d' 123)},${SHELL(printf '%d' 456)}", "123,456"));
-	TEST(test_expected_result(test, c, "${foo},${CDR(answer)},${SHELL(printf '%d' 456)}", "123,0.000000,456"));
+	TEST(test_expected_result(test, c, "${foo},${CDR(answer)},${SHELL(printf '%d' 456)}", "123,,456"));
 	TEST(test_expected_result(test, c, "${foo},${CDR(answer,u)},${SHELL(printf '%d' 456)}", "123,0.000000,456"));
 	TEST(test_expected_result(test, c, "${foo},${this_does_not_exist},${THIS_DOES_NOT_EXIST(either)}", "123,,"));
 #undef TEST