test(test_suite): added vsnprintf() test case

test/test_suite.cpp

@@ -83,6 +83,24 @@ TEST_CASE("snprintf", "[]" ) {
 }
 
 
+TEST_CASE("vsnprintf", "[]" ) {
+  char buffer[100];
+
+  // mock argument list
+  const struct tag_args {
+    int   a;
+    int   b;
+    char* s;
+  } args = { -1, -1000, "test" };
+
+  test::vsnprintf(buffer, 100U, "%d %d %s", (char*)&args);
+  REQUIRE(!strcmp(buffer, "-1 -1000 test"));
+
+  test::vsnprintf(buffer, 3U, "%d", (char*)&args);
+  REQUIRE(!strcmp(buffer, "-1"));
+}
+
+
 TEST_CASE("space flag", "[]" ) {
   char buffer[100];