Add a `claim_deadline` field to `PaymentClaimable` with guarantees
[rust-lightning] / lightning / src / ln / channelmanager.rs
index d6a203df16dabc294138efcf26151b197fd94d8a..241235fd20aeb011eab547ba76d5c1702eb784d7 100644 (file)
@@ -1496,18 +1496,31 @@ macro_rules! send_channel_ready {
        }}
 }
 
+macro_rules! emit_channel_pending_event {
+       ($locked_events: expr, $channel: expr) => {
+               if $channel.should_emit_channel_pending_event() {
+                       $locked_events.push(events::Event::ChannelPending {
+                               channel_id: $channel.channel_id(),
+                               former_temporary_channel_id: $channel.temporary_channel_id(),
+                               counterparty_node_id: $channel.get_counterparty_node_id(),
+                               user_channel_id: $channel.get_user_id(),
+                               funding_txo: $channel.get_funding_txo().unwrap().into_bitcoin_outpoint(),
+                       });
+                       $channel.set_channel_pending_event_emitted();
+               }
+       }
+}
+
 macro_rules! emit_channel_ready_event {
-       ($self: expr, $channel: expr) => {
+       ($locked_events: expr, $channel: expr) => {
                if $channel.should_emit_channel_ready_event() {
-                       {
-                               let mut pending_events = $self.pending_events.lock().unwrap();
-                               pending_events.push(events::Event::ChannelReady {
-                                       channel_id: $channel.channel_id(),
-                                       user_channel_id: $channel.get_user_id(),
-                                       counterparty_node_id: $channel.get_counterparty_node_id(),
-                                       channel_type: $channel.get_channel_type().clone(),
-                               });
-                       }
+                       debug_assert!($channel.channel_pending_event_emitted());
+                       $locked_events.push(events::Event::ChannelReady {
+                               channel_id: $channel.channel_id(),
+                               user_channel_id: $channel.get_user_id(),
+                               counterparty_node_id: $channel.get_counterparty_node_id(),
+                               channel_type: $channel.get_channel_type().clone(),
+                       });
                        $channel.set_channel_ready_event_emitted();
                }
        }
@@ -3350,8 +3363,10 @@ where
                                                                                        }
                                                                                }
                                                                                let mut total_value = claimable_htlc.sender_intended_value;
+                                                                               let mut earliest_expiry = claimable_htlc.cltv_expiry;
                                                                                for htlc in htlcs.iter() {
                                                                                        total_value += htlc.sender_intended_value;
+                                                                                       earliest_expiry = cmp::min(earliest_expiry, htlc.cltv_expiry);
                                                                                        match &htlc.onion_payload {
                                                                                                OnionPayload::Invoice { .. } => {
                                                                                                        if htlc.total_msat != $payment_data.total_msat {
@@ -3384,6 +3399,7 @@ where
                                                                                                amount_msat,
                                                                                                via_channel_id: Some(prev_channel_id),
                                                                                                via_user_channel_id: Some(prev_user_channel_id),
+                                                                                               claim_deadline: Some(earliest_expiry - HTLC_FAIL_BACK_BUFFER),
                                                                                        });
                                                                                        payment_claimable_generated = true;
                                                                                } else {
@@ -3437,6 +3453,7 @@ where
                                                                                                        hash_map::Entry::Vacant(e) => {
                                                                                                                let amount_msat = claimable_htlc.value;
                                                                                                                claimable_htlc.total_value_received = Some(amount_msat);
+                                                                                                               let claim_deadline = Some(claimable_htlc.cltv_expiry - HTLC_FAIL_BACK_BUFFER);
                                                                                                                let purpose = events::PaymentPurpose::SpontaneousPayment(preimage);
                                                                                                                e.insert((purpose.clone(), vec![claimable_htlc]));
                                                                                                                let prev_channel_id = prev_funding_outpoint.to_channel_id();
@@ -3447,6 +3464,7 @@ where
                                                                                                                        purpose,
                                                                                                                        via_channel_id: Some(prev_channel_id),
                                                                                                                        via_user_channel_id: Some(prev_user_channel_id),
+                                                                                                                       claim_deadline,
                                                                                                                });
                                                                                                        },
                                                                                                        hash_map::Entry::Occupied(_) => {
@@ -3922,9 +3940,10 @@ where
        /// Provides a payment preimage in response to [`Event::PaymentClaimable`], generating any
        /// [`MessageSendEvent`]s needed to claim the payment.
        ///
-       /// Note that calling this method does *not* guarantee that the payment has been claimed. You
-       /// *must* wait for an [`Event::PaymentClaimed`] event which upon a successful claim will be
-       /// provided to your [`EventHandler`] when [`process_pending_events`] is next called.
+       /// This method is guaranteed to ensure the payment has been claimed but only if the current
+       /// height is strictly below [`Event::PaymentClaimable::claim_deadline`]. To avoid race
+       /// conditions, you should wait for an [`Event::PaymentClaimed`] before considering the payment
+       /// successful. It will generally be available in the next [`process_pending_events`] call.
        ///
        /// Note that if you did not set an `amount_msat` when calling [`create_inbound_payment`] or
        /// [`create_inbound_payment_for_hash`] you must check that the amount in the `PaymentClaimable`
@@ -3932,6 +3951,7 @@ where
        /// the sender "proof-of-payment" when they did not fulfill the full expected payment.
        ///
        /// [`Event::PaymentClaimable`]: crate::events::Event::PaymentClaimable
+       /// [`Event::PaymentClaimable::claim_deadline`]: crate::events::Event::PaymentClaimable::claim_deadline
        /// [`Event::PaymentClaimed`]: crate::events::Event::PaymentClaimed
        /// [`process_pending_events`]: EventsProvider::process_pending_events
        /// [`create_inbound_payment`]: Self::create_inbound_payment
@@ -3968,21 +3988,10 @@ where
                };
                debug_assert!(!sources.is_empty());
 
-               // If we are claiming an MPP payment, we check that all channels which contain a claimable
-               // HTLC still exist. While this isn't guaranteed to remain true if a channel closes while
-               // we're claiming (or even after we claim, before the commitment update dance completes),
-               // it should be a relatively rare race, and we'd rather not claim HTLCs that require us to
-               // go on-chain (and lose the on-chain fee to do so) than just reject the payment.
-               //
-               // Note that we'll still always get our funds - as long as the generated
-               // `ChannelMonitorUpdate` makes it out to the relevant monitor we can claim on-chain.
-               //
-               // If we find an HTLC which we would need to claim but for which we do not have a
-               // channel, we will fail all parts of the MPP payment. While we could wait and see if
-               // the sender retries the already-failed path(s), it should be a pretty rare case where
-               // we got all the HTLCs and then a channel closed while we were waiting for the user to
-               // provide the preimage, so worrying too much about the optimal handling isn't worth
-               // it.
+               // Just in case one HTLC has been failed between when we generated the `PaymentClaimable`
+               // and when we got here we need to check that the amount we're about to claim matches the
+               // amount we told the user in the last `PaymentClaimable`. We also do a sanity-check that
+               // the MPP parts all have the same `total_msat`.
                let mut claimable_amt_msat = 0;
                let mut prev_total_msat = None;
                let mut expected_amt_msat = None;
@@ -3990,28 +3999,6 @@ where
                let mut errs = Vec::new();
                let per_peer_state = self.per_peer_state.read().unwrap();
                for htlc in sources.iter() {
-                       let (counterparty_node_id, chan_id) = match self.short_to_chan_info.read().unwrap().get(&htlc.prev_hop.short_channel_id) {
-                               Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
-                               None => {
-                                       valid_mpp = false;
-                                       break;
-                               }
-                       };
-
-                       let peer_state_mutex_opt = per_peer_state.get(&counterparty_node_id);
-                       if peer_state_mutex_opt.is_none() {
-                               valid_mpp = false;
-                               break;
-                       }
-
-                       let mut peer_state_lock = peer_state_mutex_opt.unwrap().lock().unwrap();
-                       let peer_state = &mut *peer_state_lock;
-
-                       if peer_state.channel_by_id.get(&chan_id).is_none() {
-                               valid_mpp = false;
-                               break;
-                       }
-
                        if prev_total_msat.is_some() && prev_total_msat != Some(htlc.total_msat) {
                                log_error!(self.logger, "Somehow ended up with an MPP payment with different expected total amounts - this should not be reachable!");
                                debug_assert!(false);
@@ -4253,8 +4240,6 @@ where
                        });
                }
 
-               emit_channel_ready_event!(self, channel);
-
                macro_rules! handle_cs { () => {
                        if let Some(update) = commitment_update {
                                pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
@@ -4287,6 +4272,12 @@ where
                        self.tx_broadcaster.broadcast_transaction(&tx);
                }
 
+               {
+                       let mut pending_events = self.pending_events.lock().unwrap();
+                       emit_channel_pending_event!(pending_events, channel);
+                       emit_channel_ready_event!(pending_events, channel);
+               }
+
                htlc_forwards
        }
 
@@ -4711,7 +4702,10 @@ where
                                        }
                                }
 
-                               emit_channel_ready_event!(self, chan.get_mut());
+                               {
+                                       let mut pending_events = self.pending_events.lock().unwrap();
+                                       emit_channel_ready_event!(pending_events, chan.get_mut());
+                               }
 
                                Ok(())
                        },
@@ -6036,7 +6030,10 @@ where
                                                        }
                                                }
 
-                                               emit_channel_ready_event!(self, channel);
+                                               {
+                                                       let mut pending_events = self.pending_events.lock().unwrap();
+                                                       emit_channel_ready_event!(pending_events, channel);
+                                               }
 
                                                if let Some(announcement_sigs) = announcement_sigs {
                                                        log_trace!(self.logger, "Sending announcement_signatures for channel {}", log_bytes!(channel.channel_id()));
@@ -6147,34 +6144,11 @@ where
                }
        }
 
-       /// Blocks until ChannelManager needs to be persisted or a timeout is reached. It returns a bool
-       /// indicating whether persistence is necessary. Only one listener on
-       /// [`await_persistable_update`], [`await_persistable_update_timeout`], or a future returned by
-       /// [`get_persistable_update_future`] is guaranteed to be woken up.
-       ///
-       /// Note that this method is not available with the `no-std` feature.
+       /// Gets a [`Future`] that completes when this [`ChannelManager`] needs to be persisted.
        ///
-       /// [`await_persistable_update`]: Self::await_persistable_update
-       /// [`await_persistable_update_timeout`]: Self::await_persistable_update_timeout
-       /// [`get_persistable_update_future`]: Self::get_persistable_update_future
-       #[cfg(any(test, feature = "std"))]
-       pub fn await_persistable_update_timeout(&self, max_wait: Duration) -> bool {
-               self.persistence_notifier.wait_timeout(max_wait)
-       }
-
-       /// Blocks until ChannelManager needs to be persisted. Only one listener on
-       /// [`await_persistable_update`], `await_persistable_update_timeout`, or a future returned by
-       /// [`get_persistable_update_future`] is guaranteed to be woken up.
+       /// Note that callbacks registered on the [`Future`] MUST NOT call back into this
+       /// [`ChannelManager`] and should instead register actions to be taken later.
        ///
-       /// [`await_persistable_update`]: Self::await_persistable_update
-       /// [`get_persistable_update_future`]: Self::get_persistable_update_future
-       pub fn await_persistable_update(&self) {
-               self.persistence_notifier.wait()
-       }
-
-       /// Gets a [`Future`] that completes when a persistable update is available. Note that
-       /// callbacks registered on the [`Future`] MUST NOT call back into this [`ChannelManager`] and
-       /// should instead register actions to be taken later.
        pub fn get_persistable_update_future(&self) -> Future {
                self.persistence_notifier.get_future()
        }
@@ -7355,6 +7329,7 @@ where
                let mut id_to_peer = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
                let mut short_to_chan_info = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
                let mut channel_closures = Vec::new();
+               let mut pending_background_events = Vec::new();
                for _ in 0..channel_count {
                        let mut channel: Channel<<SP::Target as SignerProvider>::Signer> = Channel::read(reader, (
                                &args.entropy_source, &args.signer_provider, best_block_height, &provided_channel_type_features(&args.default_config)
@@ -7384,9 +7359,11 @@ where
                                        log_error!(args.logger, " The channel will be force-closed and the latest commitment transaction from the ChannelMonitor broadcast.");
                                        log_error!(args.logger, " The ChannelMonitor for channel {} is at update_id {} but the ChannelManager is at update_id {}.",
                                                log_bytes!(channel.channel_id()), monitor.get_latest_update_id(), channel.get_latest_monitor_update_id());
-                                       let (_, mut new_failed_htlcs) = channel.force_shutdown(true);
+                                       let (monitor_update, mut new_failed_htlcs) = channel.force_shutdown(true);
+                                       if let Some(monitor_update) = monitor_update {
+                                               pending_background_events.push(BackgroundEvent::ClosingMonitorUpdate(monitor_update));
+                                       }
                                        failed_htlcs.append(&mut new_failed_htlcs);
-                                       monitor.broadcast_latest_holder_commitment_txn(&args.tx_broadcaster, &args.logger);
                                        channel_closures.push(events::Event::ChannelClosed {
                                                channel_id: channel.channel_id(),
                                                user_channel_id: channel.get_user_id(),
@@ -7451,10 +7428,13 @@ where
                        }
                }
 
-               for (funding_txo, monitor) in args.channel_monitors.iter_mut() {
+               for (funding_txo, _) in args.channel_monitors.iter() {
                        if !funding_txo_set.contains(funding_txo) {
-                               log_info!(args.logger, "Broadcasting latest holder commitment transaction for closed channel {}", log_bytes!(funding_txo.to_channel_id()));
-                               monitor.broadcast_latest_holder_commitment_txn(&args.tx_broadcaster, &args.logger);
+                               let monitor_update = ChannelMonitorUpdate {
+                                       update_id: CLOSED_CHANNEL_UPDATE_ID,
+                                       updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast: true }],
+                               };
+                               pending_background_events.push(BackgroundEvent::ClosingMonitorUpdate((*funding_txo, monitor_update)));
                        }
                }
 
@@ -7507,10 +7487,17 @@ where
                }
 
                let background_event_count: u64 = Readable::read(reader)?;
-               let mut pending_background_events_read: Vec<BackgroundEvent> = Vec::with_capacity(cmp::min(background_event_count as usize, MAX_ALLOC_SIZE/mem::size_of::<BackgroundEvent>()));
                for _ in 0..background_event_count {
                        match <u8 as Readable>::read(reader)? {
-                               0 => pending_background_events_read.push(BackgroundEvent::ClosingMonitorUpdate((Readable::read(reader)?, Readable::read(reader)?))),
+                               0 => {
+                                       let (funding_txo, monitor_update): (OutPoint, ChannelMonitorUpdate) = (Readable::read(reader)?, Readable::read(reader)?);
+                                       if pending_background_events.iter().find(|e| {
+                                               let BackgroundEvent::ClosingMonitorUpdate((pending_funding_txo, pending_monitor_update)) = e;
+                                               *pending_funding_txo == funding_txo && *pending_monitor_update == monitor_update
+                                       }).is_none() {
+                                               pending_background_events.push(BackgroundEvent::ClosingMonitorUpdate((funding_txo, monitor_update)));
+                                       }
+                               }
                                _ => return Err(DecodeError::InvalidValue),
                        }
                }
@@ -7885,7 +7872,7 @@ where
                        per_peer_state: FairRwLock::new(per_peer_state),
 
                        pending_events: Mutex::new(pending_events_read),
-                       pending_background_events: Mutex::new(pending_background_events_read),
+                       pending_background_events: Mutex::new(pending_background_events),
                        total_consistency_lock: RwLock::new(()),
                        persistence_notifier: Notifier::new(),
 
@@ -7916,6 +7903,7 @@ mod tests {
        use bitcoin::hashes::Hash;
        use bitcoin::hashes::sha256::Hash as Sha256;
        use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
+       #[cfg(feature = "std")]
        use core::time::Duration;
        use core::sync::atomic::Ordering;
        use crate::events::{Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, ClosureReason};
@@ -7941,9 +7929,9 @@ mod tests {
 
                // All nodes start with a persistable update pending as `create_network` connects each node
                // with all other nodes to make most tests simpler.
-               assert!(nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(nodes[2].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(nodes[1].node.get_persistable_update_future().poll_is_complete());
+               assert!(nodes[2].node.get_persistable_update_future().poll_is_complete());
 
                let mut chan = create_announced_chan_between_nodes(&nodes, 0, 1);
 
@@ -7957,19 +7945,19 @@ mod tests {
                        &nodes[0].node.get_our_node_id()).pop().unwrap();
 
                // The first two nodes (which opened a channel) should now require fresh persistence
-               assert!(nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(nodes[1].node.get_persistable_update_future().poll_is_complete());
                // ... but the last node should not.
-               assert!(!nodes[2].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[2].node.get_persistable_update_future().poll_is_complete());
                // After persisting the first two nodes they should no longer need fresh persistence.
-               assert!(!nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(!nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(!nodes[1].node.get_persistable_update_future().poll_is_complete());
 
                // Node 3, unrelated to the only channel, shouldn't care if it receives a channel_update
                // about the channel.
                nodes[2].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan.0);
                nodes[2].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan.1);
-               assert!(!nodes[2].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[2].node.get_persistable_update_future().poll_is_complete());
 
                // The nodes which are a party to the channel should also ignore messages from unrelated
                // parties.
@@ -7977,8 +7965,8 @@ mod tests {
                nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.1);
                nodes[1].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.0);
                nodes[1].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.1);
-               assert!(!nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(!nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(!nodes[1].node.get_persistable_update_future().poll_is_complete());
 
                // At this point the channel info given by peers should still be the same.
                assert_eq!(nodes[0].node.list_channels()[0], node_a_chan_info);
@@ -7995,8 +7983,8 @@ mod tests {
                // persisted and that its channel info remains the same.
                nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &as_update);
                nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &bs_update);
-               assert!(!nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(!nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(!nodes[1].node.get_persistable_update_future().poll_is_complete());
                assert_eq!(nodes[0].node.list_channels()[0], node_a_chan_info);
                assert_eq!(nodes[1].node.list_channels()[0], node_b_chan_info);
 
@@ -8004,8 +7992,8 @@ mod tests {
                // the channel info has updated.
                nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &bs_update);
                nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &as_update);
-               assert!(nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(nodes[1].node.get_persistable_update_future().poll_is_complete());
                assert_ne!(nodes[0].node.list_channels()[0], node_a_chan_info);
                assert_ne!(nodes[1].node.list_channels()[0], node_b_chan_info);
        }
@@ -8450,6 +8438,7 @@ mod tests {
                        assert_eq!(nodes_0_lock.len(), 1);
                        assert!(nodes_0_lock.contains_key(channel_id));
                }
+               expect_channel_pending_event(&nodes[1], &nodes[0].node.get_our_node_id());
 
                {
                        // Assert that `nodes[1]`'s `id_to_peer` map is populated with the channel as soon as
@@ -8462,6 +8451,7 @@ mod tests {
                let funding_signed = get_event_msg!(nodes[1], MessageSendEvent::SendFundingSigned, nodes[0].node.get_our_node_id());
                nodes[0].node.handle_funding_signed(&nodes[1].node.get_our_node_id(), &funding_signed);
                check_added_monitors!(nodes[0], 1);
+               expect_channel_pending_event(&nodes[0], &nodes[1].node.get_our_node_id());
                let (channel_ready, _) = create_chan_between_nodes_with_value_confirm(&nodes[0], &nodes[1], &tx);
                let (announcement, nodes_0_update, nodes_1_update) = create_chan_between_nodes_with_value_b(&nodes[0], &nodes[1], &channel_ready);
                update_nodes_with_chan_announce(&nodes, 0, 1, &announcement, &nodes_0_update, &nodes_1_update);
@@ -8604,10 +8594,13 @@ mod tests {
 
                                nodes[1].node.handle_funding_created(&nodes[0].node.get_our_node_id(), &funding_created_msg);
                                check_added_monitors!(nodes[1], 1);
+                               expect_channel_pending_event(&nodes[1], &nodes[0].node.get_our_node_id());
+
                                let funding_signed = get_event_msg!(nodes[1], MessageSendEvent::SendFundingSigned, nodes[0].node.get_our_node_id());
 
                                nodes[0].node.handle_funding_signed(&nodes[1].node.get_our_node_id(), &funding_signed);
                                check_added_monitors!(nodes[0], 1);
+                               expect_channel_pending_event(&nodes[0], &nodes[1].node.get_our_node_id());
                        }
                        open_channel_msg.temporary_channel_id = nodes[0].keys_manager.get_secure_random_bytes();
                }
@@ -8827,7 +8820,7 @@ pub mod bench {
        use crate::chain::chainmonitor::{ChainMonitor, Persist};
        use crate::chain::keysinterface::{EntropySource, KeysManager, InMemorySigner};
        use crate::events::{Event, MessageSendEvent, MessageSendEventsProvider};
-       use crate::ln::channelmanager::{self, BestBlock, ChainParameters, ChannelManager, PaymentHash, PaymentPreimage, PaymentId};
+       use crate::ln::channelmanager::{BestBlock, ChainParameters, ChannelManager, PaymentHash, PaymentPreimage, PaymentId};
        use crate::ln::functional_test_utils::*;
        use crate::ln::msgs::{ChannelMessageHandler, Init};
        use crate::routing::gossip::NetworkGraph;
@@ -8908,7 +8901,24 @@ pub mod bench {
                } else { panic!(); }
 
                node_b.handle_funding_created(&node_a.get_our_node_id(), &get_event_msg!(node_a_holder, MessageSendEvent::SendFundingCreated, node_b.get_our_node_id()));
+               let events_b = node_b.get_and_clear_pending_events();
+               assert_eq!(events_b.len(), 1);
+               match events_b[0] {
+                       Event::ChannelPending{ ref counterparty_node_id, .. } => {
+                               assert_eq!(*counterparty_node_id, node_a.get_our_node_id());
+                       },
+                       _ => panic!("Unexpected event"),
+               }
+
                node_a.handle_funding_signed(&node_b.get_our_node_id(), &get_event_msg!(node_b_holder, MessageSendEvent::SendFundingSigned, node_a.get_our_node_id()));
+               let events_a = node_a.get_and_clear_pending_events();
+               assert_eq!(events_a.len(), 1);
+               match events_a[0] {
+                       Event::ChannelPending{ ref counterparty_node_id, .. } => {
+                               assert_eq!(*counterparty_node_id, node_b.get_our_node_id());
+                       },
+                       _ => panic!("Unexpected event"),
+               }
 
                assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);