diff --git a/tests/test_BuiltinFunctionRegister.hpp b/tests/test_BuiltinFunctionRegister.hpp
index e062fcd92222796da9071243bda7c3e5dd253e32..236219dbef75ed5107a2b99064b5f972dddc3489 100644
--- a/tests/test_BuiltinFunctionRegister.hpp
+++ b/tests/test_BuiltinFunctionRegister.hpp
@@ -66,7 +66,7 @@ class test_BuiltinFunctionRegister
                                     [](const TinyVector<3>& x) -> double { return x[0] + x[1] + x[2]; })));
 
     m_name_builtin_function_map.insert(
-      std::make_pair("R3R2toR:R^3,R^2",
+      std::make_pair("R3R2toR:R^3*R^2",
                      std::make_shared<BuiltinFunctionEmbedder<double(TinyVector<3>, TinyVector<2>)>>(
                        [](TinyVector<3> x, TinyVector<2> y) -> double { return x[0] * y[1] + (y[0] - x[2]) * x[1]; })));