f expand mpp test coverage

Author: valentinewallace

lightning/src/routing/router.rs

@@ -4396,8 +4396,18 @@ mod tests {
 			assert_eq!(route.paths.len(), 3);
 			let mut total_amount_paid_msat = 0;
 			for path in &route.paths {
+				if payment_params.payee.blinded_route_hints().len() != 0 {
+					assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
 				if let Some(bt) = &path.blinded_tail {
 					assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
+					if bt.hops.len() > 1 {
+						assert_eq!(path.hops.last().unwrap().pubkey,
+							payment_params.payee.blinded_route_hints().iter()
+								.find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
+								.map(|(_, p)| p.introduction_node_id).unwrap());
+					} else {
+						assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
+					}
 				} else {
 					assert_eq!(path.hops.len(), 2);
 					assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);