Rework `chain::Watch` return types to make async updates less scary
[rust-lightning] / lightning / src / ln / chanmon_update_fail_tests.rs
index aca5503521e75c7b16cb3444d545226d09be057a..c0648eb2b8c3f8b5cafff2ce29a849e0d6c5b836 100644 (file)
@@ -7,7 +7,7 @@
 // You may not use this file except in accordance with one or both of these
 // licenses.
 
-//! Functional tests which test the correct handling of ChannelMonitorUpdateErr returns from
+//! Functional tests which test the correct handling of ChannelMonitorUpdateStatus returns from
 //! monitor updates.
 //! There are a bunch of these as their handling is relatively error-prone so they are split out
 //! here. See also the chanmon_fail_consistency fuzz test.
@@ -18,7 +18,7 @@ use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
 use chain::channelmonitor::{ANTI_REORG_DELAY, ChannelMonitor};
 use chain::transaction::OutPoint;
-use chain::{ChannelMonitorUpdateErr, Listen, Watch};
+use chain::{ChannelMonitorUpdateStatus, Listen, Watch};
 use ln::channelmanager::{self, ChannelManager, ChannelManagerReadArgs, RAACommitmentOrder, PaymentSendFailure};
 use ln::channel::AnnouncementSigsState;
 use ln::msgs;
@@ -50,7 +50,7 @@ fn test_simple_monitor_permanent_update_fail() {
        create_announced_chan_between_nodes(&nodes, 0, 1, channelmanager::provided_init_features(), channelmanager::provided_init_features());
 
        let (route, payment_hash_1, _, payment_secret_1) = get_route_and_payment_hash!(&nodes[0], nodes[1], 1000000);
-       chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::PermanentFailure));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::PermanentFailure);
        unwrap_send_err!(nodes[0].node.send_payment(&route, payment_hash_1, &Some(payment_secret_1)), true, APIError::ChannelUnavailable {..}, {});
        check_added_monitors!(nodes[0], 2);
 
@@ -116,7 +116,7 @@ fn test_monitor_and_persister_update_fail() {
                        &mut io::Cursor::new(&w.0), &test_utils::OnlyReadsKeysInterface {}).unwrap().1;
                assert!(new_monitor == *monitor);
                let chain_mon = test_utils::TestChainMonitor::new(Some(&chain_source), &tx_broadcaster, &logger, &chanmon_cfgs[0].fee_estimator, &persister, &node_cfgs[0].keys_manager);
-               assert!(chain_mon.watch_channel(outpoint, new_monitor).is_ok());
+               assert_eq!(chain_mon.watch_channel(outpoint, new_monitor), ChannelMonitorUpdateStatus::Completed);
                chain_mon
        };
        let header = BlockHeader {
@@ -129,8 +129,8 @@ fn test_monitor_and_persister_update_fail() {
        };
        chain_mon.chain_monitor.block_connected(&Block { header, txdata: vec![] }, 200);
 
-       // Set the persister's return value to be a TemporaryFailure.
-       persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       // Set the persister's return value to be a InProgress.
+       persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
 
        // Try to update ChannelMonitor
        nodes[1].node.claim_funds(preimage);
@@ -142,12 +142,12 @@ fn test_monitor_and_persister_update_fail() {
        nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
        if let Some(ref mut channel) = nodes[0].node.channel_state.lock().unwrap().by_id.get_mut(&chan.2) {
                if let Ok((_, _, update)) = channel.commitment_signed(&updates.commitment_signed, &node_cfgs[0].logger) {
-                       // Check that even though the persister is returning a TemporaryFailure,
+                       // Check that even though the persister is returning a InProgress,
                        // because the update is bogus, ultimately the error that's returned
                        // should be a PermanentFailure.
-                       if let Err(ChannelMonitorUpdateErr::PermanentFailure) = chain_mon.chain_monitor.update_channel(outpoint, update.clone()) {} else { panic!("Expected monitor error to be permanent"); }
-                       logger.assert_log_regex("lightning::chain::chainmonitor".to_string(), regex::Regex::new("Failed to persist ChannelMonitor update for channel [0-9a-f]*: TemporaryFailure").unwrap(), 1);
-                       if let Ok(_) = nodes[0].chain_monitor.update_channel(outpoint, update) {} else { assert!(false); }
+                       if let ChannelMonitorUpdateStatus::PermanentFailure = chain_mon.chain_monitor.update_channel(outpoint, update.clone()) {} else { panic!("Expected monitor error to be permanent"); }
+                       logger.assert_log_regex("lightning::chain::chainmonitor".to_string(), regex::Regex::new("Persistence of ChannelMonitorUpdate for channel [0-9a-f]* in progress").unwrap(), 1);
+                       assert_eq!(nodes[0].chain_monitor.update_channel(outpoint, update), ChannelMonitorUpdateStatus::Completed);
                } else { assert!(false); }
        } else { assert!(false); };
 
@@ -167,7 +167,7 @@ fn do_test_simple_monitor_temporary_update_fail(disconnect: bool) {
 
        let (route, payment_hash_1, payment_preimage_1, payment_secret_1) = get_route_and_payment_hash!(&nodes[0], nodes[1], 1000000);
 
-       chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
 
        {
                unwrap_send_err!(nodes[0].node.send_payment(&route, payment_hash_1, &Some(payment_secret_1)), false, APIError::MonitorUpdateFailed, {});
@@ -184,7 +184,7 @@ fn do_test_simple_monitor_temporary_update_fail(disconnect: bool) {
                reconnect_nodes(&nodes[0], &nodes[1], (true, true), (0, 0), (0, 0), (0, 0), (0, 0), (0, 0), (false, false));
        }
 
-       chanmon_cfgs[0].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[0].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[0].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[0], 0);
@@ -220,7 +220,7 @@ fn do_test_simple_monitor_temporary_update_fail(disconnect: bool) {
        // Now set it to failed again...
        let (route, payment_hash_2, _, payment_secret_2) = get_route_and_payment_hash!(&nodes[0], nodes[1], 1000000);
        {
-               chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+               chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
                unwrap_send_err!(nodes[0].node.send_payment(&route, payment_hash_2, &Some(payment_secret_2)), false, APIError::MonitorUpdateFailed, {});
                check_added_monitors!(nodes[0], 1);
        }
@@ -261,8 +261,8 @@ fn do_test_monitor_temporary_update_fail(disconnect_count: usize) {
        // * First we route a payment, then get a temporary monitor update failure when trying to
        //   route a second payment. We then claim the first payment.
        // * If disconnect_count is set, we will disconnect at this point (which is likely as
-       //   TemporaryFailure likely indicates net disconnect which resulted in failing to update
-       //   the ChannelMonitor on a watchtower).
+       //   InProgress likely indicates net disconnect which resulted in failing to update the
+       //   ChannelMonitor on a watchtower).
        // * If !(disconnect_count & 16) we deliver a update_fulfill_htlc/CS for the first payment
        //   immediately, otherwise we wait disconnect and deliver them via the reconnect
        //   channel_reestablish processing (ie disconnect_count & 16 makes no sense if
@@ -284,7 +284,7 @@ fn do_test_monitor_temporary_update_fail(disconnect_count: usize) {
        // Now try to send a second payment which will fail to send
        let (route, payment_hash_2, payment_preimage_2, payment_secret_2) = get_route_and_payment_hash!(nodes[0], nodes[1], 1000000);
        {
-               chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+               chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
                unwrap_send_err!(nodes[0].node.send_payment(&route, payment_hash_2, &Some(payment_secret_2)), false, APIError::MonitorUpdateFailed, {});
                check_added_monitors!(nodes[0], 1);
        }
@@ -339,7 +339,7 @@ fn do_test_monitor_temporary_update_fail(disconnect_count: usize) {
        }
 
        // Now fix monitor updating...
-       chanmon_cfgs[0].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[0].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[0].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[0], 0);
@@ -631,14 +631,14 @@ fn test_monitor_update_fail_cs() {
        let send_event = SendEvent::from_event(nodes[0].node.get_and_clear_pending_msg_events().remove(0));
        nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &send_event.commitment_msg);
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
        nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1);
        check_added_monitors!(nodes[1], 1);
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[1], 0);
@@ -662,7 +662,7 @@ fn test_monitor_update_fail_cs() {
                        assert!(updates.update_fee.is_none());
                        assert_eq!(*node_id, nodes[0].node.get_our_node_id());
 
-                       chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+                       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
                        nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &updates.commitment_signed);
                        assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
                        nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1);
@@ -672,7 +672,7 @@ fn test_monitor_update_fail_cs() {
                _ => panic!("Unexpected event"),
        }
 
-       chanmon_cfgs[0].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[0].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[0].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[0], 0);
@@ -724,7 +724,7 @@ fn test_monitor_update_fail_no_rebroadcast() {
        nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
        let bs_raa = commitment_signed_dance!(nodes[1], nodes[0], send_event.commitment_msg, false, true, false, true);
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &bs_raa);
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
        nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1);
@@ -732,7 +732,7 @@ fn test_monitor_update_fail_no_rebroadcast() {
        assert!(nodes[1].node.get_and_clear_pending_events().is_empty());
        check_added_monitors!(nodes[1], 1);
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
@@ -781,7 +781,7 @@ fn test_monitor_update_raa_while_paused() {
        check_added_monitors!(nodes[1], 1);
        let bs_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
 
-       chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[0].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &send_event_2.msgs[0]);
        nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &send_event_2.commitment_msg);
        assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
@@ -790,10 +790,10 @@ fn test_monitor_update_raa_while_paused() {
 
        nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_raa);
        assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
-       nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Previous monitor update failure prevented responses to RAA".to_string(), 1);
+       nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Existing pending monitor update prevented responses to RAA".to_string(), 1);
        check_added_monitors!(nodes[0], 1);
 
-       chanmon_cfgs[0].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[0].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[0].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[0], 0);
@@ -873,7 +873,7 @@ fn do_test_monitor_update_fail_raa(test_ignore_second_cs: bool) {
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
 
        // Now fail monitor updating.
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[1].node.handle_revoke_and_ack(&nodes[2].node.get_our_node_id(), &bs_revoke_and_ack);
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
        nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1);
@@ -889,7 +889,7 @@ fn do_test_monitor_update_fail_raa(test_ignore_second_cs: bool) {
                check_added_monitors!(nodes[0], 1);
        }
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(())); // We succeed in updating the monitor for the first channel
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed); // We succeed in updating the monitor for the first channel
        send_event = SendEvent::from_event(nodes[0].node.get_and_clear_pending_msg_events().remove(0));
        nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
        commitment_signed_dance!(nodes[1], nodes[0], send_event.commitment_msg, false, true);
@@ -919,7 +919,7 @@ fn do_test_monitor_update_fail_raa(test_ignore_second_cs: bool) {
 
        // Restore monitor updating, ensuring we immediately get a fail-back update and a
        // update_add update.
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_2.2).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[1], 0);
@@ -1123,7 +1123,7 @@ fn test_monitor_update_fail_reestablish() {
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
        commitment_signed_dance!(nodes[1], nodes[2], updates.commitment_signed, false);
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init { features: channelmanager::provided_init_features(), remote_network_address: None }).unwrap();
        nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init { features: channelmanager::provided_init_features(), remote_network_address: None }).unwrap();
 
@@ -1160,7 +1160,7 @@ fn test_monitor_update_fail_reestablish() {
                get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id())
                        .contents.flags & 2, 0); // The "disabled" bit should be unset as we just reconnected
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_1.2).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[1], 0);
@@ -1225,7 +1225,7 @@ fn raa_no_response_awaiting_raa_state() {
        // Now we have a CS queued up which adds a new HTLC (which will need a RAA/CS response from
        // nodes[1]) followed by an RAA. Fail the monitor updating prior to the CS, deliver the RAA,
        // then restore channel monitor updates.
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
        nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &payment_event.commitment_msg);
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
@@ -1234,10 +1234,10 @@ fn raa_no_response_awaiting_raa_state() {
 
        nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_raa);
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
-       nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Previous monitor update failure prevented responses to RAA".to_string(), 1);
+       nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Existing pending monitor update prevented responses to RAA".to_string(), 1);
        check_added_monitors!(nodes[1], 1);
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        // nodes[1] should be AwaitingRAA here!
@@ -1328,7 +1328,7 @@ fn claim_while_disconnected_monitor_update_fail() {
 
        // Now deliver a's reestablish, freeing the claim from the holding cell, but fail the monitor
        // update.
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
 
        nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &as_reconnect);
        let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
@@ -1355,7 +1355,7 @@ fn claim_while_disconnected_monitor_update_fail() {
 
        // Now un-fail the monitor, which will result in B sending its original commitment update,
        // receiving the commitment update from A, and the resulting commitment dances.
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[1], 0);
@@ -1434,7 +1434,7 @@ fn monitor_failed_no_reestablish_response() {
                check_added_monitors!(nodes[0], 1);
        }
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        let mut events = nodes[0].node.get_and_clear_pending_msg_events();
        assert_eq!(events.len(), 1);
        let payment_event = SendEvent::from_event(events.pop().unwrap());
@@ -1460,7 +1460,7 @@ fn monitor_failed_no_reestablish_response() {
        nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reconnect);
        let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[1], 0);
@@ -1534,7 +1534,7 @@ fn first_message_on_recv_ordering() {
        let payment_event = SendEvent::from_event(events.pop().unwrap());
        assert_eq!(payment_event.node_id, nodes[1].node.get_our_node_id());
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
 
        // Deliver the final RAA for the first payment, which does not require a response. RAAs
        // generally require a commitment_signed, so the fact that we're expecting an opposite response
@@ -1553,7 +1553,7 @@ fn first_message_on_recv_ordering() {
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
        nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Previous monitor update failure prevented generation of RAA".to_string(), 1);
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[1], 0);
@@ -1597,7 +1597,7 @@ fn test_monitor_update_fail_claim() {
 
        let (payment_preimage_1, payment_hash_1, _) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[1].node.claim_funds(payment_preimage_1);
        expect_payment_claimed!(nodes[1], payment_hash_1, 1_000_000);
        nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Temporary failure claiming HTLC, treating as success: Failed to update ChannelMonitor".to_string(), 1);
@@ -1616,7 +1616,7 @@ fn test_monitor_update_fail_claim() {
 
        // Successfully update the monitor on the 1<->2 channel, but the 0<->1 channel should still be
        // paused, so forward shouldn't succeed until we call channel_monitor_updated().
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
 
        let mut events = nodes[2].node.get_and_clear_pending_msg_events();
        assert_eq!(events.len(), 1);
@@ -1727,13 +1727,13 @@ fn test_monitor_update_on_pending_forwards() {
        nodes[1].node.handle_update_add_htlc(&nodes[2].node.get_our_node_id(), &payment_event.msgs[0]);
        commitment_signed_dance!(nodes[1], nodes[2], payment_event.commitment_msg, false);
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[1], vec![HTLCDestination::NextHopChannel { node_id: Some(nodes[2].node.get_our_node_id()), channel_id: chan_2.2 }]);
        check_added_monitors!(nodes[1], 1);
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
        nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1);
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_1.2).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[1], 0);
@@ -1787,7 +1787,7 @@ fn monitor_update_claim_fail_no_response() {
        nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
        let as_raa = commitment_signed_dance!(nodes[1], nodes[0], payment_event.commitment_msg, false, true, false, true);
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[1].node.claim_funds(payment_preimage_1);
        expect_payment_claimed!(nodes[1], payment_hash_1, 1_000_000);
        check_added_monitors!(nodes[1], 1);
@@ -1796,7 +1796,7 @@ fn monitor_update_claim_fail_no_response() {
        assert_eq!(events.len(), 0);
        nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Temporary failure claiming HTLC, treating as success: Failed to update ChannelMonitor".to_string(), 1);
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[1], 0);
@@ -1834,19 +1834,19 @@ fn do_during_funding_monitor_fail(confirm_a_first: bool, restore_b_before_conf:
        nodes[0].node.funding_transaction_generated(&temporary_channel_id, &nodes[1].node.get_our_node_id(), funding_tx.clone()).unwrap();
        check_added_monitors!(nodes[0], 0);
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        let funding_created_msg = get_event_msg!(nodes[0], MessageSendEvent::SendFundingCreated, nodes[1].node.get_our_node_id());
        let channel_id = OutPoint { txid: funding_created_msg.funding_txid, index: funding_created_msg.funding_output_index }.to_channel_id();
        nodes[1].node.handle_funding_created(&nodes[0].node.get_our_node_id(), &funding_created_msg);
        check_added_monitors!(nodes[1], 1);
 
-       chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[0].node.handle_funding_signed(&nodes[1].node.get_our_node_id(), &get_event_msg!(nodes[1], MessageSendEvent::SendFundingSigned, nodes[0].node.get_our_node_id()));
        assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
        nodes[0].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1);
        check_added_monitors!(nodes[0], 1);
        assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
-       chanmon_cfgs[0].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[0].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[0].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[0], 0);
@@ -1886,7 +1886,7 @@ fn do_during_funding_monitor_fail(confirm_a_first: bool, restore_b_before_conf:
                assert!(nodes[1].node.get_and_clear_pending_events().is_empty());
        }
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
        check_added_monitors!(nodes[1], 0);
@@ -1958,8 +1958,8 @@ fn test_path_paused_mpp() {
 
        // Set it so that the first monitor update (for the path 0 -> 1 -> 3) succeeds, but the second
        // (for the path 0 -> 2 -> 3) fails.
-       chanmon_cfgs[0].persister.set_update_ret(Ok(()));
-       chanmon_cfgs[0].persister.set_next_update_ret(Some(Err(ChannelMonitorUpdateErr::TemporaryFailure)));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
+       chanmon_cfgs[0].persister.set_next_update_ret(Some(ChannelMonitorUpdateStatus::InProgress));
 
        // Now check that we get the right return value, indicating that the first path succeeded but
        // the second got a MonitorUpdateFailed err. This implies PaymentSendFailure::PartialFailure as
@@ -1970,7 +1970,7 @@ fn test_path_paused_mpp() {
                if let Err(APIError::MonitorUpdateFailed) = results[1] {} else { panic!(); }
        } else { panic!(); }
        check_added_monitors!(nodes[0], 2);
-       chanmon_cfgs[0].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
 
        // Pass the first HTLC of the payment along to nodes[3].
        let mut events = nodes[0].node.get_and_clear_pending_msg_events();
@@ -2267,7 +2267,7 @@ fn do_channel_holding_cell_serialize(disconnect: bool, reload_a: bool) {
        nodes[0].node.send_payment(&route, payment_hash_2, &Some(payment_secret_2)).unwrap();
        check_added_monitors!(nodes[0], 0);
 
-       chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        nodes[0].node.claim_funds(payment_preimage_0);
        check_added_monitors!(nodes[0], 1);
        expect_payment_claimed!(nodes[0], payment_hash_0, 100_000);
@@ -2317,7 +2317,8 @@ fn do_channel_holding_cell_serialize(disconnect: bool, reload_a: bool) {
                        nodes[0].node = &nodes_0_deserialized;
                        assert!(nodes_0_read.is_empty());
 
-                       nodes[0].chain_monitor.watch_channel(chan_0_monitor.get_funding_txo().0.clone(), chan_0_monitor).unwrap();
+                       assert_eq!(nodes[0].chain_monitor.watch_channel(chan_0_monitor.get_funding_txo().0.clone(), chan_0_monitor),
+                               ChannelMonitorUpdateStatus::Completed);
                        check_added_monitors!(nodes[0], 1);
                } else {
                        nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id(), false);
@@ -2361,7 +2362,7 @@ fn do_channel_holding_cell_serialize(disconnect: bool, reload_a: bool) {
 
        // If we finish updating the monitor, we should free the holding cell right away (this did
        // not occur prior to #756).
-       chanmon_cfgs[0].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (funding_txo, mon_id, _) = nodes[0].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_id).unwrap().clone();
        nodes[0].chain_monitor.chain_monitor.force_channel_monitor_updated(funding_txo, mon_id);
 
@@ -2560,8 +2561,8 @@ fn test_temporary_error_during_shutdown() {
 
        let (_, _, channel_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1, channelmanager::provided_init_features(), channelmanager::provided_init_features());
 
-       chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
 
        nodes[0].node.close_channel(&channel_id, &nodes[1].node.get_our_node_id()).unwrap();
        nodes[1].node.handle_shutdown(&nodes[0].node.get_our_node_id(), &channelmanager::provided_init_features(), &get_event_msg!(nodes[0], MessageSendEvent::SendShutdown, nodes[1].node.get_our_node_id()));
@@ -2572,8 +2573,8 @@ fn test_temporary_error_during_shutdown() {
 
        assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
 
-       chanmon_cfgs[0].persister.set_update_ret(Ok(()));
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
 
        let (outpoint, latest_update, _) = nodes[0].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[0].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
@@ -2581,7 +2582,7 @@ fn test_temporary_error_during_shutdown() {
 
        assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
 
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
        let (outpoint, latest_update, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(outpoint, latest_update);
 
@@ -2614,7 +2615,7 @@ fn test_permanent_error_during_sending_shutdown() {
        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;
-       chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::PermanentFailure));
+       chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::PermanentFailure);
 
        assert!(nodes[0].node.close_channel(&channel_id, &nodes[1].node.get_our_node_id()).is_ok());
        check_closed_broadcast!(nodes[0], true);
@@ -2635,7 +2636,7 @@ fn test_permanent_error_during_handling_shutdown() {
        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;
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::PermanentFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::PermanentFailure);
 
        assert!(nodes[0].node.close_channel(&channel_id, &nodes[1].node.get_our_node_id()).is_ok());
        let shutdown = get_event_msg!(nodes[0], MessageSendEvent::SendShutdown, nodes[1].node.get_our_node_id());
@@ -2658,20 +2659,20 @@ fn double_temp_error() {
        let (payment_preimage_1, payment_hash_1, _) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
        let (payment_preimage_2, payment_hash_2, _) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        // `claim_funds` results in a ChannelMonitorUpdate.
        nodes[1].node.claim_funds(payment_preimage_1);
        check_added_monitors!(nodes[1], 1);
        expect_payment_claimed!(nodes[1], payment_hash_1, 1_000_000);
        let (funding_tx, latest_update_1, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
 
-       chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
        // Previously, this would've panicked due to a double-call to `Channel::monitor_update_failed`,
        // which had some asserts that prevented it from being called twice.
        nodes[1].node.claim_funds(payment_preimage_2);
        check_added_monitors!(nodes[1], 1);
        expect_payment_claimed!(nodes[1], payment_hash_2, 1_000_000);
-       chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+       chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
 
        let (_, latest_update_2, _) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();
        nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(funding_tx, latest_update_1);