diff --git a/addons/diagnostic/test_parameters.inc.sqf b/addons/diagnostic/test_parameters.inc.sqf
new file mode 100644
index 000000000..bbd127181
--- /dev/null
+++ b/addons/diagnostic/test_parameters.inc.sqf
@@ -0,0 +1,40 @@
+// ----------------------------------------------------------------------------
+
+#include "script_component.hpp"
+
+SCRIPT(test_parameters);
+
+// ----------------------------------------------------------------------------
+
+LOG("Testing parameters");
+
+private ["_expected", "_result", "_this"];
+
+// Test default params.
+_this = [5];
+DEFAULT_PARAM(0,_result,12);
+_expected = 5;
+TEST_OP(_result,==,_expected,"DEFAULT_PARAM");
+
+_result = nil;
+
+_this = [];
+DEFAULT_PARAM(0,_result,12);
+_expected = 12;
+TEST_OP(_result,==,_expected,"DEFAULT_PARAM");
+
+_result = nil;
+
+_this = [nil];
+DEFAULT_PARAM(0,_result,12);
+_expected = 12;
+TEST_OP(_result,==,_expected,"DEFAULT_PARAM");
+
+_result = nil;
+
+_this = nil;
+DEFAULT_PARAM(0,_result,12);
+_expected = 12;
+TEST_OP(_result,==,_expected,"DEFAULT_PARAM");
+
+nil;