Drop verbose log entries in BP when no network graph is provided
[rust-lightning] / lightning / src / ln / payment_tests.rs
index d3146a6e68667f1426e2edf55f22f28c3ea782e3..60310e9a3df33aa445af24c33fd574753d468e98 100644 (file)
 //! payments thereafter.
 
 use crate::chain::{ChannelMonitorUpdateStatus, Confirm, Listen, Watch};
-use crate::chain::channelmonitor::{ANTI_REORG_DELAY, ChannelMonitor, LATENCY_GRACE_PERIOD_BLOCKS};
+use crate::chain::channelmonitor::{ANTI_REORG_DELAY, LATENCY_GRACE_PERIOD_BLOCKS};
 use crate::chain::transaction::OutPoint;
 use crate::chain::keysinterface::KeysInterface;
 use crate::ln::channel::EXPIRE_PREV_CONFIG_TICKS;
-use crate::ln::channelmanager::{self, BREAKDOWN_TIMEOUT, ChannelManager, ChannelManagerReadArgs, MPP_TIMEOUT_TICKS, MIN_CLTV_EXPIRY_DELTA, PaymentId, PaymentSendFailure, IDEMPOTENCY_TIMEOUT_TICKS};
+use crate::ln::channelmanager::{self, BREAKDOWN_TIMEOUT, ChannelManager, MPP_TIMEOUT_TICKS, MIN_CLTV_EXPIRY_DELTA, PaymentId, PaymentSendFailure, IDEMPOTENCY_TIMEOUT_TICKS};
 use crate::ln::msgs;
 use crate::ln::msgs::ChannelMessageHandler;
 use crate::routing::router::{PaymentParameters, get_route};
 use crate::util::events::{ClosureReason, Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider};
 use crate::util::test_utils;
 use crate::util::errors::APIError;
-use crate::util::enforcing_trait_impls::EnforcingSigner;
-use crate::util::ser::{ReadableArgs, Writeable};
-use crate::io;
+use crate::util::ser::Writeable;
 
-use bitcoin::{Block, BlockHeader, BlockHash, TxMerkleNode};
+use bitcoin::{Block, BlockHeader, TxMerkleNode};
 use bitcoin::hashes::Hash;
 use bitcoin::network::constants::Network;
 
 use crate::prelude::*;
 
 use crate::ln::functional_test_utils::*;
+use crate::routing::gossip::NodeId;
 
 #[test]
 fn retry_single_path_payment() {
@@ -409,39 +408,8 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 
        // The ChannelMonitor should always be the latest version, as we're required to persist it
        // during the `commitment_signed_dance!()`.
-       let mut chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
-       get_monitor!(nodes[0], chan_id).write(&mut chan_0_monitor_serialized).unwrap();
-
-       persister = test_utils::TestPersister::new();
-       let keys_manager = &chanmon_cfgs[0].keys_manager;
-       new_chain_monitor = test_utils::TestChainMonitor::new(Some(nodes[0].chain_source), nodes[0].tx_broadcaster.clone(), nodes[0].logger, node_cfgs[0].fee_estimator, &persister, keys_manager);
-       nodes[0].chain_monitor = &new_chain_monitor;
-       let mut chan_0_monitor_read = &chan_0_monitor_serialized.0[..];
-       let (_, mut chan_0_monitor) = <(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(
-               &mut chan_0_monitor_read, keys_manager).unwrap();
-       assert!(chan_0_monitor_read.is_empty());
-
-       let mut nodes_0_read = &nodes_0_serialized[..];
-       let (_, nodes_0_deserialized_tmp) = {
-               let mut channel_monitors = HashMap::new();
-               channel_monitors.insert(chan_0_monitor.get_funding_txo().0, &mut chan_0_monitor);
-               <(BlockHash, ChannelManager<&test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>)>::read(&mut nodes_0_read, ChannelManagerReadArgs {
-                       default_config: test_default_channel_config(),
-                       keys_manager,
-                       fee_estimator: node_cfgs[0].fee_estimator,
-                       chain_monitor: nodes[0].chain_monitor,
-                       tx_broadcaster: nodes[0].tx_broadcaster.clone(),
-                       logger: nodes[0].logger,
-                       channel_monitors,
-               }).unwrap()
-       };
-       nodes_0_deserialized = nodes_0_deserialized_tmp;
-       assert!(nodes_0_read.is_empty());
-
-       assert_eq!(nodes[0].chain_monitor.watch_channel(chan_0_monitor.get_funding_txo().0, chan_0_monitor),
-               ChannelMonitorUpdateStatus::Completed);
-       nodes[0].node = &nodes_0_deserialized;
-       check_added_monitors!(nodes[0], 1);
+       let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
+       reload_node!(nodes[0], test_default_channel_config(), &nodes_0_serialized, &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_0_deserialized);
 
        // On reload, the ChannelManager should realize it is stale compared to the ChannelMonitor and
        // force-close the channel.
@@ -603,64 +571,10 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 
        // The ChannelMonitor should always be the latest version, as we're required to persist it
        // during the `commitment_signed_dance!()`.
-       let mut chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
-       get_monitor!(nodes[0], chan_id).write(&mut chan_0_monitor_serialized).unwrap();
-
-       let mut chan_1_monitor_serialized = test_utils::TestVecWriter(Vec::new());
-
-       macro_rules! reload_node {
-               ($chain_monitor: ident, $chan_manager: ident, $persister: ident) => { {
-                       $persister = test_utils::TestPersister::new();
-                       let keys_manager = &chanmon_cfgs[0].keys_manager;
-                       $chain_monitor = test_utils::TestChainMonitor::new(Some(nodes[0].chain_source), nodes[0].tx_broadcaster.clone(), nodes[0].logger, node_cfgs[0].fee_estimator, &$persister, keys_manager);
-                       nodes[0].chain_monitor = &$chain_monitor;
-                       let mut chan_0_monitor_read = &chan_0_monitor_serialized.0[..];
-                       let (_, mut chan_0_monitor) = <(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(
-                               &mut chan_0_monitor_read, keys_manager).unwrap();
-                       assert!(chan_0_monitor_read.is_empty());
-
-                       let mut chan_1_monitor = None;
-                       let mut channel_monitors = HashMap::new();
-                       channel_monitors.insert(chan_0_monitor.get_funding_txo().0, &mut chan_0_monitor);
-
-                       if !chan_1_monitor_serialized.0.is_empty() {
-                               let mut chan_1_monitor_read = &chan_1_monitor_serialized.0[..];
-                               chan_1_monitor = Some(<(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(
-                                       &mut chan_1_monitor_read, keys_manager).unwrap().1);
-                               assert!(chan_1_monitor_read.is_empty());
-                               channel_monitors.insert(chan_1_monitor.as_ref().unwrap().get_funding_txo().0, chan_1_monitor.as_mut().unwrap());
-                       }
-
-                       let mut nodes_0_read = &nodes_0_serialized[..];
-                       let (_, nodes_0_deserialized_tmp) = {
-                               <(BlockHash, ChannelManager<&test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>)>::read(&mut nodes_0_read, ChannelManagerReadArgs {
-                                       default_config: test_default_channel_config(),
-                                       keys_manager,
-                                       fee_estimator: node_cfgs[0].fee_estimator,
-                                       chain_monitor: nodes[0].chain_monitor,
-                                       tx_broadcaster: nodes[0].tx_broadcaster.clone(),
-                                       logger: nodes[0].logger,
-                                       channel_monitors,
-                               }).unwrap()
-                       };
-                       $chan_manager = nodes_0_deserialized_tmp;
-                       assert!(nodes_0_read.is_empty());
-
-                       assert_eq!(nodes[0].chain_monitor.watch_channel(chan_0_monitor.get_funding_txo().0, chan_0_monitor),
-                               ChannelMonitorUpdateStatus::Completed);
-                       if !chan_1_monitor_serialized.0.is_empty() {
-                               let funding_txo = chan_1_monitor.as_ref().unwrap().get_funding_txo().0;
-                               assert_eq!(nodes[0].chain_monitor.watch_channel(funding_txo, chan_1_monitor.unwrap()),
-                                       ChannelMonitorUpdateStatus::Completed);
-                       }
-                       nodes[0].node = &$chan_manager;
-                       check_added_monitors!(nodes[0], if !chan_1_monitor_serialized.0.is_empty() { 2 } else { 1 });
-
-                       nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id(), false);
-               } }
-       }
+       let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
 
-       reload_node!(first_new_chain_monitor, first_nodes_0_deserialized, first_persister);
+       reload_node!(nodes[0], test_default_channel_config(), nodes_0_serialized, &[&chan_0_monitor_serialized], first_persister, first_new_chain_monitor, first_nodes_0_deserialized);
+       nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id(), false);
 
        // On reload, the ChannelManager should realize it is stale compared to the ChannelMonitor and
        // force-close the channel.
@@ -744,16 +658,16 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
        // We set mpp_parts_remain to avoid having abandon_payment called
        expect_payment_failed_conditions(&nodes[0], payment_hash, false, PaymentFailedConditions::new().mpp_parts_remain());
 
-       chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
-       get_monitor!(nodes[0], chan_id).write(&mut chan_0_monitor_serialized).unwrap();
-       chan_1_monitor_serialized = test_utils::TestVecWriter(Vec::new());
-       get_monitor!(nodes[0], chan_id_3).write(&mut chan_1_monitor_serialized).unwrap();
+       let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
+       let chan_1_monitor_serialized = get_monitor!(nodes[0], chan_id_3).encode();
        nodes_0_serialized = nodes[0].node.encode();
 
        assert!(nodes[0].node.retry_payment(&new_route, payment_id).is_ok());
        assert!(!nodes[0].node.get_and_clear_pending_msg_events().is_empty());
 
-       reload_node!(second_new_chain_monitor, second_nodes_0_deserialized, second_persister);
+       reload_node!(nodes[0], test_default_channel_config(), nodes_0_serialized, &[&chan_0_monitor_serialized, &chan_1_monitor_serialized], second_persister, second_new_chain_monitor, second_nodes_0_deserialized);
+       nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id(), false);
+
        reconnect_nodes(&nodes[0], &nodes[1], (true, true), (0, 0), (0, 0), (0, 0), (0, 0), (0, 0), (false, false));
 
        // Now resend the payment, delivering the HTLC and actually claiming it this time. This ensures
@@ -766,14 +680,14 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
        assert!(nodes[0].node.retry_payment(&new_route, payment_id).is_err());
        assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
 
-       chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
-       get_monitor!(nodes[0], chan_id).write(&mut chan_0_monitor_serialized).unwrap();
-       chan_1_monitor_serialized = test_utils::TestVecWriter(Vec::new());
-       get_monitor!(nodes[0], chan_id_3).write(&mut chan_1_monitor_serialized).unwrap();
+       let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
+       let chan_1_monitor_serialized = get_monitor!(nodes[0], chan_id_3).encode();
        nodes_0_serialized = nodes[0].node.encode();
 
        // Ensure that after reload we cannot retry the payment.
-       reload_node!(third_new_chain_monitor, third_nodes_0_deserialized, third_persister);
+       reload_node!(nodes[0], test_default_channel_config(), nodes_0_serialized, &[&chan_0_monitor_serialized, &chan_1_monitor_serialized], third_persister, third_new_chain_monitor, third_nodes_0_deserialized);
+       nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id(), false);
+
        reconnect_nodes(&nodes[0], &nodes[1], (false, false), (0, 0), (0, 0), (0, 0), (0, 0), (0, 0), (false, false));
 
        assert!(nodes[0].node.retry_payment(&new_route, payment_id).is_err());
@@ -879,16 +793,15 @@ fn do_test_dup_htlc_onchain_fails_on_reload(persist_manager_post_event: bool, co
 
        // If we persist the ChannelManager here, we should get the PaymentSent event after
        // deserialization.
-       let mut chan_manager_serialized = test_utils::TestVecWriter(Vec::new());
+       let mut chan_manager_serialized = Vec::new();
        if !persist_manager_post_event {
-               nodes[0].node.write(&mut chan_manager_serialized).unwrap();
+               chan_manager_serialized = nodes[0].node.encode();
        }
 
        // Now persist the ChannelMonitor and inform the ChainMonitor that we're done, generating the
        // payment sent event.
        chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
-       let mut chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
-       get_monitor!(nodes[0], chan_id).write(&mut chan_0_monitor_serialized).unwrap();
+       let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
        for update in mon_updates {
                nodes[0].chain_monitor.chain_monitor.channel_monitor_updated(funding_txo, update).unwrap();
        }
@@ -901,39 +814,11 @@ fn do_test_dup_htlc_onchain_fails_on_reload(persist_manager_post_event: bool, co
        // If we persist the ChannelManager after we get the PaymentSent event, we shouldn't get it
        // twice.
        if persist_manager_post_event {
-               nodes[0].node.write(&mut chan_manager_serialized).unwrap();
+               chan_manager_serialized = nodes[0].node.encode();
        }
 
        // Now reload nodes[0]...
-       persister = test_utils::TestPersister::new();
-       let keys_manager = &chanmon_cfgs[0].keys_manager;
-       new_chain_monitor = test_utils::TestChainMonitor::new(Some(nodes[0].chain_source), nodes[0].tx_broadcaster.clone(), nodes[0].logger, node_cfgs[0].fee_estimator, &persister, keys_manager);
-       nodes[0].chain_monitor = &new_chain_monitor;
-       let mut chan_0_monitor_read = &chan_0_monitor_serialized.0[..];
-       let (_, mut chan_0_monitor) = <(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(
-               &mut chan_0_monitor_read, keys_manager).unwrap();
-       assert!(chan_0_monitor_read.is_empty());
-
-       let (_, nodes_0_deserialized_tmp) = {
-               let mut channel_monitors = HashMap::new();
-               channel_monitors.insert(chan_0_monitor.get_funding_txo().0, &mut chan_0_monitor);
-               <(BlockHash, ChannelManager<&test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>)>
-                       ::read(&mut io::Cursor::new(&chan_manager_serialized.0[..]), ChannelManagerReadArgs {
-                               default_config: Default::default(),
-                               keys_manager,
-                               fee_estimator: node_cfgs[0].fee_estimator,
-                               chain_monitor: nodes[0].chain_monitor,
-                               tx_broadcaster: nodes[0].tx_broadcaster.clone(),
-                               logger: nodes[0].logger,
-                               channel_monitors,
-                       }).unwrap()
-       };
-       nodes_0_deserialized = nodes_0_deserialized_tmp;
-
-       assert_eq!(nodes[0].chain_monitor.watch_channel(chan_0_monitor.get_funding_txo().0, chan_0_monitor),
-               ChannelMonitorUpdateStatus::Completed);
-       check_added_monitors!(nodes[0], 1);
-       nodes[0].node = &nodes_0_deserialized;
+       reload_node!(nodes[0], &chan_manager_serialized, &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_0_deserialized);
 
        if persist_manager_post_event {
                assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
@@ -982,10 +867,8 @@ fn test_fulfill_restart_failure() {
 
        // The simplest way to get a failure after a fulfill is to reload nodes[1] from a state
        // pre-fulfill, which we do by serializing it here.
-       let mut chan_manager_serialized = test_utils::TestVecWriter(Vec::new());
-       nodes[1].node.write(&mut chan_manager_serialized).unwrap();
-       let mut chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
-       get_monitor!(nodes[1], chan_id).write(&mut chan_0_monitor_serialized).unwrap();
+       let chan_manager_serialized = nodes[1].node.encode();
+       let chan_0_monitor_serialized = get_monitor!(nodes[1], chan_id).encode();
 
        nodes[1].node.claim_funds(payment_preimage);
        check_added_monitors!(nodes[1], 1);
@@ -996,35 +879,7 @@ fn test_fulfill_restart_failure() {
        expect_payment_sent_without_paths!(nodes[0], payment_preimage);
 
        // Now reload nodes[1]...
-       persister = test_utils::TestPersister::new();
-       let keys_manager = &chanmon_cfgs[1].keys_manager;
-       new_chain_monitor = test_utils::TestChainMonitor::new(Some(nodes[1].chain_source), nodes[1].tx_broadcaster.clone(), nodes[1].logger, node_cfgs[1].fee_estimator, &persister, keys_manager);
-       nodes[1].chain_monitor = &new_chain_monitor;
-       let mut chan_0_monitor_read = &chan_0_monitor_serialized.0[..];
-       let (_, mut chan_0_monitor) = <(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(
-               &mut chan_0_monitor_read, keys_manager).unwrap();
-       assert!(chan_0_monitor_read.is_empty());
-
-       let (_, nodes_1_deserialized_tmp) = {
-               let mut channel_monitors = HashMap::new();
-               channel_monitors.insert(chan_0_monitor.get_funding_txo().0, &mut chan_0_monitor);
-               <(BlockHash, ChannelManager<&test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>)>
-                       ::read(&mut io::Cursor::new(&chan_manager_serialized.0[..]), ChannelManagerReadArgs {
-                               default_config: Default::default(),
-                               keys_manager,
-                               fee_estimator: node_cfgs[1].fee_estimator,
-                               chain_monitor: nodes[1].chain_monitor,
-                               tx_broadcaster: nodes[1].tx_broadcaster.clone(),
-                               logger: nodes[1].logger,
-                               channel_monitors,
-                       }).unwrap()
-       };
-       nodes_1_deserialized = nodes_1_deserialized_tmp;
-
-       assert_eq!(nodes[1].chain_monitor.watch_channel(chan_0_monitor.get_funding_txo().0, chan_0_monitor),
-               ChannelMonitorUpdateStatus::Completed);
-       check_added_monitors!(nodes[1], 1);
-       nodes[1].node = &nodes_1_deserialized;
+       reload_node!(nodes[1], &chan_manager_serialized, &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_1_deserialized);
 
        nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id(), false);
        reconnect_nodes(&nodes[0], &nodes[1], (false, false), (0, 0), (0, 0), (0, 0), (0, 0), (0, 0), (false, false));
@@ -1385,3 +1240,133 @@ fn abandoned_send_payment_idempotent() {
        pass_along_route(&nodes[0], &[&[&nodes[1]]], 100_000, second_payment_hash, second_payment_secret);
        claim_payment(&nodes[0], &[&nodes[1]], second_payment_preimage);
 }
+
+#[test]
+fn test_trivial_inflight_htlc_tracking(){
+       // In this test, we test three scenarios:
+       // (1) Sending + claiming a payment successfully should return `None` when querying InFlightHtlcs
+       // (2) Sending a payment without claiming it should return the payment's value (500000) when querying InFlightHtlcs
+       // (3) After we claim the payment sent in (2), InFlightHtlcs should return `None` for the query.
+       let chanmon_cfgs = create_chanmon_cfgs(3);
+       let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
+       let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
+       let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
+
+       let (_, _, chan_1_id, _) = create_announced_chan_between_nodes(&nodes, 0, 1, channelmanager::provided_init_features(), channelmanager::provided_init_features());
+       let (_, _, chan_2_id, _) = create_announced_chan_between_nodes(&nodes, 1, 2, channelmanager::provided_init_features(), channelmanager::provided_init_features());
+
+       // Send and claim the payment. Inflight HTLCs should be empty.
+       send_payment(&nodes[0], &vec!(&nodes[1], &nodes[2])[..], 500000);
+       {
+               let inflight_htlcs = node_chanmgrs[0].compute_inflight_htlcs();
+
+               let node_0_channel_lock = nodes[0].node.channel_state.lock().unwrap();
+               let node_1_channel_lock = nodes[1].node.channel_state.lock().unwrap();
+               let channel_1 = node_0_channel_lock.by_id.get(&chan_1_id).unwrap();
+               let channel_2 = node_1_channel_lock.by_id.get(&chan_2_id).unwrap();
+
+               let chan_1_used_liquidity = inflight_htlcs.used_liquidity_msat(
+                       &NodeId::from_pubkey(&nodes[0].node.get_our_node_id()) ,
+                       &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()),
+                       channel_1.get_short_channel_id().unwrap()
+               );
+               let chan_2_used_liquidity = inflight_htlcs.used_liquidity_msat(
+                       &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()) ,
+                       &NodeId::from_pubkey(&nodes[2].node.get_our_node_id()),
+                       channel_2.get_short_channel_id().unwrap()
+               );
+
+               assert_eq!(chan_1_used_liquidity, None);
+               assert_eq!(chan_2_used_liquidity, None);
+       }
+
+       // Send the payment, but do not claim it. Our inflight HTLCs should contain the pending payment.
+       let (payment_preimage, _,  _) = route_payment(&nodes[0], &vec!(&nodes[1], &nodes[2])[..], 500000);
+       {
+               let inflight_htlcs = node_chanmgrs[0].compute_inflight_htlcs();
+
+               let node_0_channel_lock = nodes[0].node.channel_state.lock().unwrap();
+               let node_1_channel_lock = nodes[1].node.channel_state.lock().unwrap();
+               let channel_1 = node_0_channel_lock.by_id.get(&chan_1_id).unwrap();
+               let channel_2 = node_1_channel_lock.by_id.get(&chan_2_id).unwrap();
+
+               let chan_1_used_liquidity = inflight_htlcs.used_liquidity_msat(
+                       &NodeId::from_pubkey(&nodes[0].node.get_our_node_id()) ,
+                       &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()),
+                       channel_1.get_short_channel_id().unwrap()
+               );
+               let chan_2_used_liquidity = inflight_htlcs.used_liquidity_msat(
+                       &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()) ,
+                       &NodeId::from_pubkey(&nodes[2].node.get_our_node_id()),
+                       channel_2.get_short_channel_id().unwrap()
+               );
+
+               // First hop accounts for expected 1000 msat fee
+               assert_eq!(chan_1_used_liquidity, Some(501000));
+               assert_eq!(chan_2_used_liquidity, Some(500000));
+       }
+
+       // Now, let's claim the payment. This should result in the used liquidity to return `None`.
+       claim_payment(&nodes[0], &[&nodes[1], &nodes[2]], payment_preimage);
+       {
+               let inflight_htlcs = node_chanmgrs[0].compute_inflight_htlcs();
+
+               let node_0_channel_lock = nodes[0].node.channel_state.lock().unwrap();
+               let node_1_channel_lock = nodes[1].node.channel_state.lock().unwrap();
+               let channel_1 = node_0_channel_lock.by_id.get(&chan_1_id).unwrap();
+               let channel_2 = node_1_channel_lock.by_id.get(&chan_2_id).unwrap();
+
+               let chan_1_used_liquidity = inflight_htlcs.used_liquidity_msat(
+                       &NodeId::from_pubkey(&nodes[0].node.get_our_node_id()) ,
+                       &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()),
+                       channel_1.get_short_channel_id().unwrap()
+               );
+               let chan_2_used_liquidity = inflight_htlcs.used_liquidity_msat(
+                       &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()) ,
+                       &NodeId::from_pubkey(&nodes[2].node.get_our_node_id()),
+                       channel_2.get_short_channel_id().unwrap()
+               );
+
+               assert_eq!(chan_1_used_liquidity, None);
+               assert_eq!(chan_2_used_liquidity, None);
+       }
+}
+
+#[test]
+fn test_holding_cell_inflight_htlcs() {
+       let chanmon_cfgs = create_chanmon_cfgs(2);
+       let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
+       let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
+       let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
+       let channel_id = create_announced_chan_between_nodes(&nodes, 0, 1, channelmanager::provided_init_features(), channelmanager::provided_init_features()).2;
+
+       let (route, payment_hash_1, _, payment_secret_1) = get_route_and_payment_hash!(nodes[0], nodes[1], 1000000);
+       let (_, payment_hash_2, payment_secret_2) = get_payment_preimage_hash!(nodes[1]);
+
+       // Queue up two payments - one will be delivered right away, one immediately goes into the
+       // holding cell as nodes[0] is AwaitingRAA.
+       {
+               nodes[0].node.send_payment(&route, payment_hash_1, &Some(payment_secret_1), PaymentId(payment_hash_1.0)).unwrap();
+               check_added_monitors!(nodes[0], 1);
+               nodes[0].node.send_payment(&route, payment_hash_2, &Some(payment_secret_2), PaymentId(payment_hash_2.0)).unwrap();
+               check_added_monitors!(nodes[0], 0);
+       }
+
+       let inflight_htlcs = node_chanmgrs[0].compute_inflight_htlcs();
+
+       {
+               let channel_lock = nodes[0].node.channel_state.lock().unwrap();
+               let channel = channel_lock.by_id.get(&channel_id).unwrap();
+
+               let used_liquidity = inflight_htlcs.used_liquidity_msat(
+                       &NodeId::from_pubkey(&nodes[0].node.get_our_node_id()) ,
+                       &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()),
+                       channel.get_short_channel_id().unwrap()
+               );
+
+               assert_eq!(used_liquidity, Some(2000000));
+       }
+
+       // Clear pending events so test doesn't throw a "Had excess message on node..." error
+       nodes[0].node.get_and_clear_pending_msg_events();
+}