Support fee overpayment by 1 msat in expect_payment_forwarded test util.

See ClaimAlongRouteArgs::allow_1_msat_fee_overpay.

diff --git a/lightning/src/ln/chanmon_update_fail_tests.rs b/lightning/src/ln/chanmon_update_fail_tests.rs
index 4d9316db79f8f9157aff3989001a116283e23d82..2e95f5c63ff7e173bb5a107f0719fb89ca3e3301 100644 (file)
--- a/lightning/src/ln/chanmon_update_fail_tests.rs
+++ b/lightning/src/ln/chanmon_update_fail_tests.rs
@@ -3405,7 +3405,7 @@ fn do_test_reload_mon_update_completion_actions(close_during_reload: bool) {
        let mut events = nodes[1].node.get_and_clear_pending_events();
        assert_eq!(events.len(), if close_during_reload { 2 } else { 1 });
        expect_payment_forwarded(events.pop().unwrap(), &nodes[1], &nodes[0], &nodes[2], Some(1000),
-               None, close_during_reload, false);
+               None, close_during_reload, false, false);
        if close_during_reload {
                match events[0] {
                        Event::ChannelClosed { .. } => {},

diff --git a/lightning/src/ln/functional_test_utils.rs b/lightning/src/ln/functional_test_utils.rs
index 5246737b5c747c29cb3068ff9d2163a710f547b9..47728185df3e201bd21bca83fbf0336e7fd5f160 100644 (file)
--- a/lightning/src/ln/functional_test_utils.rs
+++ b/lightning/src/ln/functional_test_utils.rs
@@ -2223,17 +2223,26 @@ macro_rules! expect_payment_path_successful {
        }
 }
 
+/// Returns the total fee earned by this HTLC forward, in msat.
 pub fn expect_payment_forwarded<CM: AChannelManager, H: NodeHolder<CM=CM>>(
        event: Event, node: &H, prev_node: &H, next_node: &H, expected_fee: Option<u64>,
        expected_extra_fees_msat: Option<u64>, upstream_force_closed: bool,
-       downstream_force_closed: bool
-) {
+       downstream_force_closed: bool, allow_1_msat_fee_overpay: bool,
+) -> Option<u64> {
        match event {
                Event::PaymentForwarded {
                        total_fee_earned_msat, prev_channel_id, claim_from_onchain_tx, next_channel_id,
                        outbound_amount_forwarded_msat: _, skimmed_fee_msat
                } => {
-                       assert_eq!(total_fee_earned_msat, expected_fee);
+                       if allow_1_msat_fee_overpay {
+                               // Aggregating fees for blinded paths may result in a rounding error, causing slight
+                               // overpayment in fees.
+                               let actual_fee = total_fee_earned_msat.unwrap();
+                               let expected_fee = expected_fee.unwrap();
+                               assert!(actual_fee == expected_fee || actual_fee == expected_fee + 1);
+                       } else {
+                               assert_eq!(total_fee_earned_msat, expected_fee);
+                       }
 
                        // Check that the (knowingly) withheld amount is always less or equal to the expected
                        // overpaid amount.
@@ -2248,6 +2257,7 @@ pub fn expect_payment_forwarded<CM: AChannelManager, H: NodeHolder<CM=CM>>(
                                assert!(node.node().list_channels().iter().any(|x| x.counterparty.node_id == next_node.node().get_our_node_id() && x.channel_id == next_channel_id.unwrap()));
                        }
                        assert_eq!(claim_from_onchain_tx, downstream_force_closed);
+                       total_fee_earned_msat
                },
                _ => panic!("Unexpected event"),
        }
@@ -2260,7 +2270,7 @@ macro_rules! expect_payment_forwarded {
                assert_eq!(events.len(), 1);
                $crate::ln::functional_test_utils::expect_payment_forwarded(
                        events.pop().unwrap(), &$node, &$prev_node, &$next_node, $expected_fee, None,
-                       $upstream_force_closed, $downstream_force_closed
+                       $upstream_force_closed, $downstream_force_closed, false
                );
        }
 }
@@ -2814,7 +2824,7 @@ pub fn pass_claimed_payment_along_route<'a, 'b, 'c, 'd>(args: ClaimAlongRouteArg
                                        let mut events = $node.node.get_and_clear_pending_events();
                                        assert_eq!(events.len(), 1);
                                        expect_payment_forwarded(events.pop().unwrap(), *$node, $next_node, $prev_node,
-                                               Some(fee as u64), expected_extra_fee, false, false);
+                                               Some(fee as u64), expected_extra_fee, false, false, false);
                                        expected_total_fee_msat += fee as u64;
                                        fwd_amt_msat += fee as u64;
                                        check_added_monitors!($node, 1);