diff --git a/tests/all.sh b/tests/all.sh
index f468518..8bc9a7c 100644
--- a/tests/all.sh
+++ b/tests/all.sh
@@ -182,7 +182,7 @@ testDiscoverScriptReturnsData() {
 testDiscoverScriptDebug() {
   DATA=$(sudo bash "/etc/zabbix/zabbix_php_fpm_discovery.sh" "debug" "/php-fpm-status")
   ERRORS_LIST=$(echo "$DATA" | grep -F 'Error:')
-  assertNull "Discover script errors: $ERRORS_LIST" "$ERRORS_LIST"
+  assertNull "Discover script errors: $DATA" "$ERRORS_LIST"
 }
 
 testZabbixDiscoverReturnsData() {