add test_calculate_shared_secret_with_identity_point

accounts/src/key_management/mod.rs

@@ -151,6 +151,20 @@ mod tests {
         assert!(address_key_holder.address.as_slice().len() > 0); // Assume TreeHashType has non-zero length for a valid address
     }
 
+    #[test]
+    fn test_calculate_shared_secret_with_identity_point() {
+        let address_key_holder = AddressKeyHolder::new_os_random();
+
+        // Use identity point as ephemeral public key
+        let identity_point = AffinePoint::identity();
+
+        // Calculate shared secret
+        let shared_secret = address_key_holder.calculate_shared_secret_receiver(identity_point);
+
+        // The shared secret with the identity point should also result in the identity point
+        assert!(Into::<bool>::into(shared_secret.is_identity()));
+    }
+
     #[test]
     fn key_generation_test() {
         let seed_holder = SeedHolder::new_os_random();