lightning 0.3.0-beta1

#![cfg_attr(rustfmt, rustfmt_skip)]

// This file is Copyright its original authors, visible in version control
// history.
//
// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
// You may not use this file except in accordance with one or both of these
// licenses.

//! Functional tests which test for correct behavior across node restarts.

use crate::chain::{BlockLocator, ChannelMonitorUpdateStatus, Watch};
use crate::chain::chaininterface::LowerBoundedFeeEstimator;
use crate::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdateStep};
use crate::routing::router::{PaymentParameters, RouteParameters};
use crate::sign::EntropySource;
use crate::chain::transaction::OutPoint;
use crate::events::{ClosureReason, Event, HTLCHandlingFailureType};
use crate::ln::channelmanager::{ChannelManager, ChannelManagerReadArgs, PaymentId, RAACommitmentOrder};
use crate::ln::outbound_payment::RecipientOnionFields;
use crate::ln::msgs;
use crate::ln::types::ChannelId;
use crate::ln::msgs::{BaseMessageHandler, ChannelMessageHandler, RoutingMessageHandler, ErrorAction, MessageSendEvent};
use crate::util::test_channel_signer::TestChannelSigner;
use crate::util::test_utils;
use crate::util::errors::APIError;
use crate::util::ser::{Writeable, ReadableArgs};
use crate::util::config::{HTLCInterceptionFlags, UserConfig};

use bitcoin::hashes::Hash;
use types::payment::{PaymentHash, PaymentPreimage};

use crate::prelude::*;

use crate::ln::functional_test_utils::*;

#[test]
fn test_funding_peer_disconnect() {
	// Test that we can lock in our funding tx while disconnected
	let chanmon_cfgs = create_chanmon_cfgs(2);
	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;

	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
	let nodes_0_deserialized;
	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
	let tx = create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 100000, 10001);

	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());

	confirm_transaction(&nodes[0], &tx);
	let events_1 = nodes[0].node.get_and_clear_pending_msg_events();
	assert!(events_1.is_empty());

	let mut reconnect_args = ReconnectArgs::new(&nodes[0], &nodes[1]);
	reconnect_args.send_channel_ready.1 = true;
	reconnect_nodes(reconnect_args);

	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());

	confirm_transaction(&nodes[1], &tx);
	let events_2 = nodes[1].node.get_and_clear_pending_msg_events();
	assert!(events_2.is_empty());

	nodes[0].node.peer_connected(nodes[1].node.get_our_node_id(), &msgs::Init {
		features: nodes[1].node.init_features(), networks: None, remote_network_address: None
	}, true).unwrap();
	let as_reestablish = get_chan_reestablish_msgs!(nodes[0], nodes[1]).pop().unwrap();
	nodes[1].node.peer_connected(nodes[0].node.get_our_node_id(), &msgs::Init {
		features: nodes[0].node.init_features(), networks: None, remote_network_address: None
	}, false).unwrap();
	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();

	// nodes[0] hasn't yet received a channel_ready, so it only sends that on reconnect.
	nodes[0].node.handle_channel_reestablish(nodes[1].node.get_our_node_id(), &bs_reestablish);
	let events_3 = nodes[0].node.get_and_clear_pending_msg_events();
	assert_eq!(events_3.len(), 1);
	let as_channel_ready = match events_3[0] {
		MessageSendEvent::SendChannelReady { ref node_id, ref msg } => {
			assert_eq!(*node_id, nodes[1].node.get_our_node_id());
			msg.clone()
		},
		_ => panic!("Unexpected event {:?}", events_3[0]),
	};

	// nodes[1] received nodes[0]'s channel_ready on the first reconnect above, so it should send
	// announcement_signatures as well as channel_update.
	nodes[1].node.handle_channel_reestablish(nodes[0].node.get_our_node_id(), &as_reestablish);
	let events_4 = nodes[1].node.get_and_clear_pending_msg_events();
	assert_eq!(events_4.len(), 3);
	let chan_id;
	let bs_channel_ready = match events_4[0] {
		MessageSendEvent::SendChannelReady { ref node_id, ref msg } => {
			assert_eq!(*node_id, nodes[0].node.get_our_node_id());
			chan_id = msg.channel_id;
			msg.clone()
		},
		_ => panic!("Unexpected event {:?}", events_4[0]),
	};
	let bs_announcement_sigs = match events_4[1] {
		MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
			assert_eq!(*node_id, nodes[0].node.get_our_node_id());
			msg.clone()
		},
		_ => panic!("Unexpected event {:?}", events_4[1]),
	};
	match events_4[2] {
		MessageSendEvent::SendChannelUpdate { ref node_id, msg: _ } => {
			assert_eq!(*node_id, nodes[0].node.get_our_node_id());
		},
		_ => panic!("Unexpected event {:?}", events_4[2]),
	}

	// Re-deliver nodes[0]'s channel_ready, which nodes[1] can safely ignore. It currently
	// generates a duplicative private channel_update
	nodes[1].node.handle_channel_ready(nodes[0].node.get_our_node_id(), &as_channel_ready);
	let events_5 = nodes[1].node.get_and_clear_pending_msg_events();
	assert_eq!(events_5.len(), 1);
	match events_5[0] {
		MessageSendEvent::SendChannelUpdate { ref node_id, msg: _ } => {
			assert_eq!(*node_id, nodes[0].node.get_our_node_id());
		},
		_ => panic!("Unexpected event {:?}", events_5[0]),
	};

	// When we deliver nodes[1]'s channel_ready, however, nodes[0] will generate its
	// announcement_signatures.
	nodes[0].node.handle_channel_ready(nodes[1].node.get_our_node_id(), &bs_channel_ready);
	let events_6 = nodes[0].node.get_and_clear_pending_msg_events();
	assert_eq!(events_6.len(), 1);
	let as_announcement_sigs = match events_6[0] {
		MessageSendEvent::SendAnnouncementSignatures { ref node_id, ref msg } => {
			assert_eq!(*node_id, nodes[1].node.get_our_node_id());
			msg.clone()
		},
		_ => panic!("Unexpected event {:?}", events_6[0]),
	};
	expect_channel_ready_event(&nodes[0], &nodes[1].node.get_our_node_id());
	expect_channel_ready_event(&nodes[1], &nodes[0].node.get_our_node_id());

	// When we deliver nodes[1]'s announcement_signatures to nodes[0], nodes[0] should immediately
	// broadcast the channel announcement globally, as well as re-send its (now-public)
	// channel_update.
	nodes[0].node.handle_announcement_signatures(nodes[1].node.get_our_node_id(), &bs_announcement_sigs);
	let events_7 = nodes[0].node.get_and_clear_pending_msg_events();
	assert_eq!(events_7.len(), 1);
	let (chan_announcement, as_update) = match events_7[0] {
		MessageSendEvent::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
			(msg.clone(), update_msg.clone().unwrap())
		},
		_ => panic!("Unexpected event {:?}", events_7[0]),
	};

	// Finally, deliver nodes[0]'s announcement_signatures to nodes[1] and make sure it creates the
	// same channel_announcement.
	nodes[1].node.handle_announcement_signatures(nodes[0].node.get_our_node_id(), &as_announcement_sigs);
	let events_8 = nodes[1].node.get_and_clear_pending_msg_events();
	assert_eq!(events_8.len(), 1);
	let bs_update = match events_8[0] {
		MessageSendEvent::BroadcastChannelAnnouncement { ref msg, ref update_msg } => {
			assert_eq!(*msg, chan_announcement);
			update_msg.clone().unwrap()
		},
		_ => panic!("Unexpected event {:?}", events_8[0]),
	};

	// Provide the channel announcement and public updates to the network graph
	let node_1_pubkey = nodes[1].node.get_our_node_id();
	nodes[0].gossip_sync.handle_channel_announcement(Some(node_1_pubkey), &chan_announcement).unwrap();
	nodes[0].gossip_sync.handle_channel_update(Some(node_1_pubkey), &bs_update).unwrap();
	nodes[0].gossip_sync.handle_channel_update(Some(node_1_pubkey), &as_update).unwrap();

	let (route, _, _, _) = get_route_and_payment_hash!(nodes[0], nodes[1], 1000000);
	let payment_preimage = send_along_route(&nodes[0], route, &[&nodes[1]], 1000000).0;
	claim_payment(&nodes[0], &[&nodes[1]], payment_preimage);

	// Check that after deserialization and reconnection we can still generate an identical
	// channel_announcement from the cached signatures.
	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());

	let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();

	reload_node!(nodes[0], &nodes[0].node.encode(), &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_0_deserialized);

	reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[1]));
}

#[test]
fn test_no_txn_manager_serialize_deserialize() {
	let chanmon_cfgs = create_chanmon_cfgs(2);
	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;

	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
	let nodes_0_deserialized;
	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);

	let tx = create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 100000, 10001);

	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());

	let chan_0_monitor_serialized =
		get_monitor!(nodes[0], ChannelId::v1_from_funding_outpoint(OutPoint { txid: tx.compute_txid(), index: 0 })).encode();
	reload_node!(nodes[0], nodes[0].node.encode(), &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_0_deserialized);

	nodes[0].node.peer_connected(nodes[1].node.get_our_node_id(), &msgs::Init {
		features: nodes[1].node.init_features(), networks: None, remote_network_address: None
	}, true).unwrap();
	let reestablish_1 = get_chan_reestablish_msgs!(nodes[0], nodes[1]);
	nodes[1].node.peer_connected(nodes[0].node.get_our_node_id(), &msgs::Init {
		features: nodes[0].node.init_features(), networks: None, remote_network_address: None
	}, false).unwrap();
	let reestablish_2 = get_chan_reestablish_msgs!(nodes[1], nodes[0]);

	nodes[1].node.handle_channel_reestablish(nodes[0].node.get_our_node_id(), &reestablish_1[0]);
	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
	nodes[0].node.handle_channel_reestablish(nodes[1].node.get_our_node_id(), &reestablish_2[0]);
	assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());

	let (channel_ready, _) = create_chan_between_nodes_with_value_confirm(&nodes[0], &nodes[1], &tx);
	let (announcement, as_update, bs_update) = create_chan_between_nodes_with_value_b(&nodes[0], &nodes[1], &channel_ready);
	for (i, node) in nodes.iter().enumerate() {
		let counterparty_node_id = nodes[(i + 1) % 2].node.get_our_node_id();
		assert!(node.gossip_sync.handle_channel_announcement(Some(counterparty_node_id), &announcement).unwrap());
		node.gossip_sync.handle_channel_update(Some(counterparty_node_id), &as_update).unwrap();
		node.gossip_sync.handle_channel_update(Some(counterparty_node_id), &bs_update).unwrap();
	}

	send_payment(&nodes[0], &[&nodes[1]], 1000000);
}

#[test]
fn test_manager_serialize_deserialize_events() {
	// This test makes sure the events field in ChannelManager survives de/serialization
	let chanmon_cfgs = create_chanmon_cfgs(2);
	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;

	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
	let nodes_0_deserialized;
	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);

	// Start creating a channel, but stop right before broadcasting the funding transaction
	let channel_value = 100000;
	let push_msat = 10001;
	let node_a = nodes.remove(0);
	let node_b = nodes.remove(0);
	node_a.node.create_channel(node_b.node.get_our_node_id(), channel_value, push_msat, 42, None, None).unwrap();
	handle_and_accept_open_channel(&node_b, node_a.node.get_our_node_id(), &get_event_msg!(node_a, MessageSendEvent::SendOpenChannel, node_b.node.get_our_node_id()));
	node_a.node.handle_accept_channel(node_b.node.get_our_node_id(), &get_event_msg!(node_b, MessageSendEvent::SendAcceptChannel, node_a.node.get_our_node_id()));

	let (temporary_channel_id, tx, funding_output) = create_funding_transaction(&node_a, &node_b.node.get_our_node_id(), channel_value, 42);

	node_a.node.funding_transaction_generated(temporary_channel_id, node_b.node.get_our_node_id(), tx.clone()).unwrap();
	check_added_monitors(&node_a, 0);

	let funding_created = get_event_msg!(node_a, MessageSendEvent::SendFundingCreated, node_b.node.get_our_node_id());
	let channel_id = ChannelId::v1_from_funding_txid(
		funding_created.funding_txid.as_byte_array(), funding_created.funding_output_index
	);

	node_b.node.handle_funding_created(node_a.node.get_our_node_id(), &funding_created);
	{
		let mut added_monitors = node_b.chain_monitor.added_monitors.lock().unwrap();
		assert_eq!(added_monitors.len(), 1);
		assert_eq!(added_monitors[0].0, channel_id);
		added_monitors.clear();
	}

	let bs_funding_signed = get_event_msg!(node_b, MessageSendEvent::SendFundingSigned, node_a.node.get_our_node_id());
	node_a.node.handle_funding_signed(node_b.node.get_our_node_id(), &bs_funding_signed);
	{
		let mut added_monitors = node_a.chain_monitor.added_monitors.lock().unwrap();
		assert_eq!(added_monitors.len(), 1);
		assert_eq!(added_monitors[0].0, channel_id);
		added_monitors.clear();
	}
	// Normally, this is where node_a would broadcast the funding transaction, but the test de/serializes first instead

	expect_channel_pending_event(&node_a, &node_b.node.get_our_node_id());
	expect_channel_pending_event(&node_b, &node_a.node.get_our_node_id());

	nodes.push(node_a);
	nodes.push(node_b);

	// Start the de/seriailization process mid-channel creation to check that the channel manager will hold onto events that are serialized
	let chan_0_monitor_serialized = get_monitor!(nodes[0], bs_funding_signed.channel_id).encode();
	reload_node!(nodes[0], nodes[0].node.encode(), &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_0_deserialized);

	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());

	// After deserializing, make sure the funding_transaction is still held by the channel manager
	let events_4 = nodes[0].node.get_and_clear_pending_events();
	assert_eq!(events_4.len(), 0);
	assert_eq!(nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().len(), 1);
	assert_eq!(nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap()[0].compute_txid(), funding_output.txid);

	// Make sure the channel is functioning as though the de/serialization never happened
	assert_eq!(nodes[0].node.list_channels().len(), 1);

	nodes[0].node.peer_connected(nodes[1].node.get_our_node_id(), &msgs::Init {
		features: nodes[1].node.init_features(), networks: None, remote_network_address: None
	}, true).unwrap();
	let reestablish_1 = get_chan_reestablish_msgs!(nodes[0], nodes[1]);
	nodes[1].node.peer_connected(nodes[0].node.get_our_node_id(), &msgs::Init {
		features: nodes[0].node.init_features(), networks: None, remote_network_address: None
	}, false).unwrap();
	let reestablish_2 = get_chan_reestablish_msgs!(nodes[1], nodes[0]);

	nodes[1].node.handle_channel_reestablish(nodes[0].node.get_our_node_id(), &reestablish_1[0]);
	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
	nodes[0].node.handle_channel_reestablish(nodes[1].node.get_our_node_id(), &reestablish_2[0]);
	assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());

	let (channel_ready, _) = create_chan_between_nodes_with_value_confirm(&nodes[0], &nodes[1], &tx);
	let (announcement, as_update, bs_update) = create_chan_between_nodes_with_value_b(&nodes[0], &nodes[1], &channel_ready);
	for (i, node) in nodes.iter().enumerate() {
		let counterparty_node_id = nodes[(i + 1) % 2].node.get_our_node_id();
		assert!(node.gossip_sync.handle_channel_announcement(Some(counterparty_node_id), &announcement).unwrap());
		node.gossip_sync.handle_channel_update(Some(counterparty_node_id), &as_update).unwrap();
		node.gossip_sync.handle_channel_update(Some(counterparty_node_id), &bs_update).unwrap();
	}

	send_payment(&nodes[0], &[&nodes[1]], 1000000);
}

#[test]
fn test_simple_manager_serialize_deserialize() {
	let chanmon_cfgs = create_chanmon_cfgs(2);
	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;

	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
	let nodes_0_deserialized;
	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
	let chan_id = create_announced_chan_between_nodes(&nodes, 0, 1).2;

	let (our_payment_preimage, ..) = route_payment(&nodes[0], &[&nodes[1]], 1000000);
	let (_, our_payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1]], 1000000);

	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());

	let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
	reload_node!(nodes[0], nodes[0].node.encode(), &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_0_deserialized);

	reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[1]));

	fail_payment(&nodes[0], &[&nodes[1]], our_payment_hash);
	claim_payment(&nodes[0], &[&nodes[1]], our_payment_preimage);
}

#[test]
fn test_manager_serialize_deserialize_inconsistent_monitor() {
	// Test deserializing a ChannelManager with an out-of-date ChannelMonitor
	let chanmon_cfgs = create_chanmon_cfgs(4);
	let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
	let logger;
	let fee_estimator;
	let persister;
	let new_chain_monitor;

	let legacy_cfg = test_legacy_channel_config();
	let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[Some(legacy_cfg.clone()), Some(legacy_cfg.clone()), Some(legacy_cfg.clone()), Some(legacy_cfg)]);
	let nodes_0_deserialized;
	let mut nodes = create_network(4, &node_cfgs, &node_chanmgrs);

	let chan_id_1 = create_announced_chan_between_nodes(&nodes, 0, 1).2;
	let chan_id_2 = create_announced_chan_between_nodes(&nodes, 2, 0).2;
	let (_, _, channel_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 3);

	let mut node_0_stale_monitors_serialized = Vec::new();
	for chan_id_iter in &[chan_id_1, chan_id_2, channel_id] {
		let mut writer = test_utils::TestVecWriter(Vec::new());
		get_monitor!(nodes[0], *chan_id_iter).write(&mut writer).unwrap();
		node_0_stale_monitors_serialized.push(writer.0);
	}

	let (our_payment_preimage, ..) = route_payment(&nodes[2], &[&nodes[0], &nodes[1]], 1000000);

	// Serialize the ChannelManager here, but the monitor we keep up-to-date
	let nodes_0_serialized = nodes[0].node.encode();

	route_payment(&nodes[0], &[&nodes[3]], 1000000);
	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());
	nodes[2].node.peer_disconnected(nodes[0].node.get_our_node_id());
	nodes[3].node.peer_disconnected(nodes[0].node.get_our_node_id());

	// Now the ChannelMonitor (which is now out-of-sync with ChannelManager for channel w/
	// nodes[3])
	let mut node_0_monitors_serialized = Vec::new();
	for chan_id_iter in &[chan_id_1, chan_id_2, channel_id] {
		node_0_monitors_serialized.push(get_monitor!(nodes[0], *chan_id_iter).encode());
	}

	logger = test_utils::TestLogger::new();
	fee_estimator = test_utils::TestFeeEstimator::new(253);
	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, &logger, &fee_estimator, &persister, keys_manager);
	nodes[0].chain_monitor = &new_chain_monitor;


	let mut node_0_stale_monitors = Vec::new();
	for serialized in node_0_stale_monitors_serialized.iter() {
		let mut read = &serialized[..];
		let (_, monitor) = <(BlockLocator, ChannelMonitor<TestChannelSigner>)>::read(&mut read, (keys_manager, keys_manager)).unwrap();
		assert!(read.is_empty());
		node_0_stale_monitors.push(monitor);
	}

	let mut node_0_monitors = Vec::new();
	for serialized in node_0_monitors_serialized.iter() {
		let mut read = &serialized[..];
		let (_, monitor) = <(BlockLocator, ChannelMonitor<TestChannelSigner>)>::read(&mut read, (keys_manager, keys_manager)).unwrap();
		assert!(read.is_empty());
		node_0_monitors.push(monitor);
	}

	let mut nodes_0_read = &nodes_0_serialized[..];
	if let Err(msgs::DecodeError::DangerousValue) =
		<(BlockLocator, ChannelManager<&test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestKeysInterface, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestRouter, &test_utils::TestMessageRouter, &test_utils::TestLogger>)>::read(&mut nodes_0_read, ChannelManagerReadArgs {
		config: UserConfig::default(),
		entropy_source: keys_manager,
		node_signer: keys_manager,
		signer_provider: keys_manager,
		fee_estimator: &fee_estimator,
		router: &nodes[0].router,
		message_router: &nodes[0].message_router,
		chain_monitor: nodes[0].chain_monitor,
		tx_broadcaster: nodes[0].tx_broadcaster,
		logger: &logger,
		channel_monitors: node_0_stale_monitors.iter().map(|monitor| { (monitor.channel_id(), monitor) }).collect(),
		reconstruct_manager_from_monitors: None,
	}) { } else {
		panic!("If the monitor(s) are stale, this indicates a bug and we should get an Err return");
	};

	let mut nodes_0_read = &nodes_0_serialized[..];
	let (_, nodes_0_deserialized_tmp) =
		<(BlockLocator, ChannelManager<&test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestKeysInterface, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestRouter, &test_utils::TestMessageRouter, &test_utils::TestLogger>)>::read(&mut nodes_0_read, ChannelManagerReadArgs {
		config: UserConfig::default(),
		entropy_source: keys_manager,
		node_signer: keys_manager,
		signer_provider: keys_manager,
		fee_estimator: &fee_estimator,
		router: nodes[0].router,
		message_router: &nodes[0].message_router,
		chain_monitor: nodes[0].chain_monitor,
		tx_broadcaster: nodes[0].tx_broadcaster,
		logger: &logger,
		channel_monitors: node_0_monitors.iter().map(|monitor| { (monitor.channel_id(), monitor) }).collect(),
		reconstruct_manager_from_monitors: None,
	}).unwrap();
	nodes_0_deserialized = nodes_0_deserialized_tmp;
	assert!(nodes_0_read.is_empty());

	for monitor in node_0_monitors.drain(..) {
		assert_eq!(nodes[0].chain_monitor.watch_channel(monitor.channel_id(), monitor),
			Ok(ChannelMonitorUpdateStatus::Completed));
	check_added_monitors(&nodes[0], 1);
	}
	nodes[0].node = &nodes_0_deserialized;

	check_closed_event(&nodes[0], 1, ClosureReason::OutdatedChannelManager, &[nodes[3].node.get_our_node_id()], 100000);
	{ // Channel close should result in a commitment tx
		nodes[0].node.timer_tick_occurred();
		let txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
		assert_eq!(txn.len(), 1);
		check_spends!(txn[0], funding_tx);
		assert_eq!(txn[0].input[0].previous_output.txid, funding_tx.compute_txid());
	}
	check_added_monitors(&nodes[0], 1);

	// nodes[1] and nodes[2] have no lost state with nodes[0]...
	reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[1]));
	reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[2]));
	//... and we can even still claim the payment!
	claim_payment(&nodes[2], &[&nodes[0], &nodes[1]], our_payment_preimage);

	nodes[3].node.peer_connected(nodes[0].node.get_our_node_id(), &msgs::Init {
		features: nodes[0].node.init_features(), networks: None, remote_network_address: None
	}, true).unwrap();
	let reestablish = get_chan_reestablish_msgs!(nodes[3], nodes[0]).pop().unwrap();
	nodes[0].node.peer_connected(nodes[3].node.get_our_node_id(), &msgs::Init {
		features: nodes[3].node.init_features(), networks: None, remote_network_address: None
	}, false).unwrap();
	nodes[0].node.handle_channel_reestablish(nodes[3].node.get_our_node_id(), &reestablish);
	let mut found_err = false;
	for msg_event in nodes[0].node.get_and_clear_pending_msg_events() {
		if let MessageSendEvent::HandleError { ref action, .. } = msg_event {
			match action {
				&ErrorAction::SendErrorMessage { ref msg } => {
					assert_eq!(msg.channel_id, channel_id);
					assert!(!found_err);
					found_err = true;
				},
				_ => panic!("Unexpected event!"),
			}
		}
	}
	assert!(found_err);
}

#[cfg(feature = "std")]
fn do_test_data_loss_protect(reconnect_panicing: bool, substantially_old: bool, not_stale: bool) {
	use crate::ln::outbound_payment::Retry;
	use crate::types::string::UntrustedString;
	// When we get a data_loss_protect proving we're behind, we immediately panic as the
	// chain::Watch API requirements have been violated (e.g. the user restored from a backup). The
	// panic message informs the user they should force-close without broadcasting, which is tested
	// if `reconnect_panicing` is not set.
	let mut chanmon_cfgs = create_chanmon_cfgs(2);
	// We broadcast during Drop because chanmon is out of sync with chanmgr, which would cause a panic
	// during signing due to revoked tx
	chanmon_cfgs[0].keys_manager.disable_revocation_policy_check = true;
	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;

	let legacy_cfg = test_legacy_channel_config();
	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[Some(legacy_cfg.clone()), Some(legacy_cfg)]);
	let nodes_0_deserialized;

	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);

	let chan = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1000000, 1000000);

	// Cache node A state before any channel update
	let previous_node_state = nodes[0].node.encode();
	let previous_chain_monitor_state = get_monitor!(nodes[0], chan.2).encode();

	assert!(!substantially_old || !not_stale, "substantially_old and not_stale doesn't make sense");
	if not_stale || !substantially_old {
		// Previously, we'd only hit the data_loss_protect assertion if we had a state which
		// revoked at least two revocations ago, not the latest revocation. Here, we use
		// `not_stale` to test the boundary condition.
		let pay_params = PaymentParameters::for_keysend(nodes[1].node.get_our_node_id(), 100, false);
		let route_params = RouteParameters::from_payment_params_and_value(pay_params, 40000);
		nodes[0].node.send_spontaneous_payment(None, RecipientOnionFields::spontaneous_empty(40000), PaymentId([0; 32]), route_params, Retry::Attempts(0)).unwrap();
		check_added_monitors(&nodes[0], 1);
		let update_add_commit = SendEvent::from_node(&nodes[0]);

		nodes[1].node.handle_update_add_htlc(nodes[0].node.get_our_node_id(), &update_add_commit.msgs[0]);
		nodes[1].node.handle_commitment_signed_batch_test(nodes[0].node.get_our_node_id(), &update_add_commit.commitment_msg);
		check_added_monitors(&nodes[1], 1);
		let (raa, cs) = get_revoke_commit_msgs(&nodes[1], &nodes[0].node.get_our_node_id());

		nodes[0].node.handle_revoke_and_ack(nodes[1].node.get_our_node_id(), &raa);
		check_added_monitors(&nodes[0], 1);
		assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
		if !not_stale {
			nodes[0].node.handle_commitment_signed_batch_test(nodes[1].node.get_our_node_id(), &cs);
			check_added_monitors(&nodes[0], 1);
			// A now revokes their original state, at which point reconnect should panic
			let raa = get_event_msg!(nodes[0], MessageSendEvent::SendRevokeAndACK, nodes[1].node.get_our_node_id());
			nodes[1].node.handle_revoke_and_ack(nodes[0].node.get_our_node_id(), &raa);
			check_added_monitors(&nodes[1], 1);
			expect_htlc_failure_conditions(nodes[1].node.get_and_clear_pending_events(), &[]);
		}
	} else {
		send_payment(&nodes[0], &[&nodes[1]], 8000000);
		send_payment(&nodes[0], &[&nodes[1]], 8000000);
	}

	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());

	reload_node!(nodes[0], previous_node_state, &[&previous_chain_monitor_state], persister, new_chain_monitor, nodes_0_deserialized);

	if reconnect_panicing {
		nodes[0].node.peer_connected(nodes[1].node.get_our_node_id(), &msgs::Init {
			features: nodes[1].node.init_features(), networks: None, remote_network_address: None
		}, true).unwrap();
		nodes[1].node.peer_connected(nodes[0].node.get_our_node_id(), &msgs::Init {
			features: nodes[0].node.init_features(), networks: None, remote_network_address: None
		}, false).unwrap();

		let reestablish_1 = get_chan_reestablish_msgs!(nodes[0], nodes[1]);

		// If A has fallen behind substantially, B should send it a message letting it know
		// that.
		nodes[1].node.handle_channel_reestablish(nodes[0].node.get_our_node_id(), &reestablish_1[0]);
		let reestablish_msg;
		if substantially_old {
			let warn_msg = "Peer attempted to reestablish channel with a very old local commitment transaction: 0 (received) vs 4 (expected)".to_owned();

			let warn_reestablish = nodes[1].node.get_and_clear_pending_msg_events();
			assert_eq!(warn_reestablish.len(), 2);
			match warn_reestablish[1] {
				MessageSendEvent::HandleError { action: ErrorAction::SendWarningMessage { ref msg, .. }, .. } => {
					assert_eq!(msg.data, warn_msg);
				},
				_ => panic!("Unexpected events: {:?}", warn_reestablish),
			}
			reestablish_msg = match &warn_reestablish[0] {
				MessageSendEvent::SendChannelReestablish { msg, .. } => msg.clone(),
				_ => panic!("Unexpected events: {:?}", warn_reestablish),
			};
		} else {
			let msgs = nodes[1].node.get_and_clear_pending_msg_events();
			assert!(msgs.len() >= 4);
			match msgs.last() {
				Some(MessageSendEvent::SendChannelUpdate { .. }) => {},
				_ => panic!("Unexpected events: {:?}", msgs),
			}
			assert!(msgs.iter().any(|msg| matches!(msg, MessageSendEvent::SendRevokeAndACK { .. })));
			assert!(msgs.iter().any(|msg| matches!(msg, MessageSendEvent::UpdateHTLCs { .. })));
			reestablish_msg = match &msgs[0] {
				MessageSendEvent::SendChannelReestablish { msg, .. } => msg.clone(),
				_ => panic!("Unexpected events: {:?}", msgs),
			};
		}

		{
			let mut node_txn = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap();
			// The node B should never force-close the channel.
			assert!(node_txn.is_empty());
		}

		// Check A panics upon seeing proof it has fallen behind.
		let reconnect_res = std::panic::catch_unwind(|| {
			nodes[0].node.handle_channel_reestablish(nodes[1].node.get_our_node_id(), &reestablish_msg);
		});
		if not_stale {
			assert!(reconnect_res.is_ok());
			// At this point A gets confused because B expects a commitment state newer than A
			// has sent, but not a newer revocation secret, so A just (correctly) closes.
			check_closed_broadcast(&nodes[0], 1, true);
			check_added_monitors(&nodes[0], 1);
			check_closed_event(&nodes[0], 1, ClosureReason::ProcessingError {
				err: "Peer attempted to reestablish channel with a future remote commitment transaction: 2 (received) vs 1 (expected)".to_owned()
			}, &[nodes[1].node.get_our_node_id()], 1000000);
		} else {
			assert!(reconnect_res.is_err());
			// Skip the `Drop` handler for `Node`s as some may be in an invalid (panicked) state.
			std::mem::forget(nodes);
		}
	} else {
		let message = "Channel force-closed".to_owned();
		assert!(!not_stale, "We only care about the stale case when not testing panicking");

		nodes[0]
			.node
			.force_close_broadcasting_latest_txn(&chan.2, &nodes[1].node.get_our_node_id(), message.clone())
			.unwrap();
		check_added_monitors(&nodes[0], 1);
		let reason =
			ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
		check_closed_event(&nodes[0], 1, reason, &[nodes[1].node.get_our_node_id()], 1000000);
		{
			let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
			assert_eq!(node_txn.len(), 1);
		}

		for msg in nodes[0].node.get_and_clear_pending_msg_events() {
			if let MessageSendEvent::BroadcastChannelUpdate { .. } = msg {
			} else if let MessageSendEvent::HandleError { ref action, .. } = msg {
				match action {
					&ErrorAction::SendErrorMessage { ref msg } => {
						assert_eq!(&msg.data, "Channel force-closed");
					},
					_ => panic!("Unexpected event!"),
				}
			} else {
				panic!("Unexpected event {:?}", msg)
			}
		}

		// after the warning message sent by B, we should not able to
		// use the channel, or reconnect with success to the channel.
		assert!(nodes[0].node.list_usable_channels().is_empty());
		nodes[0].node.peer_connected(nodes[1].node.get_our_node_id(), &msgs::Init {
			features: nodes[1].node.init_features(), networks: None, remote_network_address: None
		}, true).unwrap();
		nodes[1].node.peer_connected(nodes[0].node.get_our_node_id(), &msgs::Init {
			features: nodes[0].node.init_features(), networks: None, remote_network_address: None
		}, false).unwrap();
		let retry_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]);

		nodes[0].node.handle_channel_reestablish(nodes[1].node.get_our_node_id(), &retry_reestablish[0]);
		let mut err_msgs_0 = Vec::with_capacity(1);
		if let MessageSendEvent::HandleError { ref action, .. } = nodes[0].node.get_and_clear_pending_msg_events()[1] {
			match action {
				&ErrorAction::SendErrorMessage { ref msg } => {
					let peer_msg = format!(
						"Got a message for a channel from the wrong node! No such channel_id {} for the passed counterparty_node_id {}",
						chan.2, nodes[1].node.get_our_node_id()
					);
					assert_eq!(msg.data, peer_msg);
					err_msgs_0.push(msg.clone());
				},
				_ => panic!("Unexpected event!"),
			}
		} else {
			panic!("Unexpected event!");
		}
		assert_eq!(err_msgs_0.len(), 1);
		nodes[1].node.handle_error(nodes[0].node.get_our_node_id(), &err_msgs_0[0]);
		assert!(nodes[1].node.list_usable_channels().is_empty());
		check_added_monitors(&nodes[1], 1);
		let peer_msg = format!(
			"Got a message for a channel from the wrong node! No such channel_id {} for the passed counterparty_node_id {}",
			chan.2, nodes[1].node.get_our_node_id()
		);
		let reason = ClosureReason::CounterpartyForceClosed { peer_msg: UntrustedString(peer_msg) };
		check_closed_event(&nodes[1], 1, reason, &[nodes[0].node.get_our_node_id()], 1000000);
		check_closed_broadcast(&nodes[1], 1, false);
	}
}

#[test]
#[cfg(feature = "std")]
fn test_data_loss_protect() {
	do_test_data_loss_protect(true, false, true);
	do_test_data_loss_protect(true, true, false);
	do_test_data_loss_protect(true, false, false);
	do_test_data_loss_protect(false, true, false);
	do_test_data_loss_protect(false, false, false);
}

fn do_test_partial_claim_before_restart(persist_both_monitors: bool, double_restart: bool) {
	// Test what happens if a node receives an MPP payment, claims it, but crashes before
	// persisting the ChannelManager. If `persist_both_monitors` is false, also crash after only
	// updating one of the two channels' ChannelMonitors. As a result, on startup, we'll (a) still
	// have the PaymentClaimable event, (b) have one (or two) channel(s) that goes on chain with the
	// HTLC preimage in them, and (c) optionally have one channel that is live off-chain but does
	// not have the preimage tied to the still-pending HTLC.
	//
	// To get to the correct state, on startup we should propagate the preimage to the
	// still-off-chain channel, claiming the HTLC as soon as the peer connects, with the monitor
	// receiving the preimage without a state update.
	//
	// Further, we should generate a `PaymentClaimed` event to inform the user that the payment was
	// definitely claimed.
	let chanmon_cfgs = create_chanmon_cfgs(4);
	let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
	let (persist_d_1, persist_d_2);
	let (chain_d_1, chain_d_2);

	let mut config = test_default_channel_config();
	// Set the percentage to the default value at the time this test was written
	config.channel_handshake_config.announced_channel_max_inbound_htlc_value_in_flight_percentage = 10;
	let configs: [Option<UserConfig>; 4] = core::array::from_fn(|_| Some(config.clone()));
	let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &configs);
	let (node_d_1, node_d_2);

	let mut nodes = create_network(4, &node_cfgs, &node_chanmgrs);

	create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100_000, 0);
	create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 100_000, 0);
	let chan_id_persisted = create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 100_000, 0).2;
	let chan_id_not_persisted = create_announced_chan_between_nodes_with_value(&nodes, 2, 3, 100_000, 0).2;

	// Create an MPP route for 15k sats, more than the default htlc-max of 10%
	let (mut route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[3], 15_000_000);
	assert_eq!(route.paths.len(), 2);
	route.paths.sort_by(|path_a, _| {
		// Sort the path so that the path through nodes[1] comes first
		if path_a.hops[0].pubkey == nodes[1].node.get_our_node_id() {
			core::cmp::Ordering::Less } else { core::cmp::Ordering::Greater }
	});

	nodes[0].node.send_payment_with_route(route, payment_hash,
		RecipientOnionFields::secret_only(payment_secret, 15_000_000), PaymentId(payment_hash.0)).unwrap();
	check_added_monitors(&nodes[0], 2);

	// Send the payment through to nodes[3] *without* clearing the PaymentClaimable event
	let mut send_events = nodes[0].node.get_and_clear_pending_msg_events();
	assert_eq!(send_events.len(), 2);
	let node_1_msgs = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut send_events);
	let node_2_msgs = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut send_events);
	do_pass_along_path(PassAlongPathArgs::new(&nodes[0],&[&nodes[1], &nodes[3]], 15_000_000, payment_hash, node_1_msgs)
		.with_payment_secret(payment_secret)
		.without_clearing_recipient_events());
	do_pass_along_path(PassAlongPathArgs::new(&nodes[0], &[&nodes[2], &nodes[3]], 15_000_000, payment_hash, node_2_msgs)
		.with_payment_secret(payment_secret)
		.without_clearing_recipient_events());

	// Now that we have an MPP payment pending, get the latest encoded copies of nodes[3]'s
	// monitors and ChannelManager, for use later, if we don't want to persist both monitors.
	let mut original_monitor = test_utils::TestVecWriter(Vec::new());
	if !persist_both_monitors {
		for channel_id in nodes[3].chain_monitor.chain_monitor.list_monitors() {
			if channel_id == chan_id_not_persisted {
				assert!(original_monitor.0.is_empty());
				nodes[3].chain_monitor.chain_monitor.get_monitor(channel_id).unwrap().write(&mut original_monitor).unwrap();
			}
		}
	}

	let original_manager = nodes[3].node.encode();

	expect_payment_claimable!(nodes[3], payment_hash, payment_secret, 15_000_000);

	nodes[3].node.claim_funds(payment_preimage);
	check_added_monitors(&nodes[3], 2);
	expect_payment_claimed!(nodes[3], payment_hash, 15_000_000);

	// Now fetch one of the two updated ChannelMonitors from nodes[3], and restart pretending we
	// crashed in between the two persistence calls - using one old ChannelMonitor and one new one,
	// with the old ChannelManager.
	let mut updated_monitor = test_utils::TestVecWriter(Vec::new());
	for channel_id in nodes[3].chain_monitor.chain_monitor.list_monitors() {
		if channel_id == chan_id_persisted {
			assert!(updated_monitor.0.is_empty());
			nodes[3].chain_monitor.chain_monitor.get_monitor(channel_id).unwrap().write(&mut updated_monitor).unwrap();
		}
	}
	// If `persist_both_monitors` is set, get the second monitor here as well
	if persist_both_monitors {
		for channel_id in nodes[3].chain_monitor.chain_monitor.list_monitors() {
			if channel_id == chan_id_not_persisted {
				assert!(original_monitor.0.is_empty());
				nodes[3].chain_monitor.chain_monitor.get_monitor(channel_id).unwrap().write(&mut original_monitor).unwrap();
			}
		}
	}

	// Now restart nodes[3].
	reload_node!(nodes[3], original_manager.clone(), &[&updated_monitor.0, &original_monitor.0], persist_d_1, chain_d_1, node_d_1);
	nodes[3].disable_monitor_completeness_assertion();

	if double_restart {
		// Previously, we had a bug where we'd fail to reload if we re-persist the `ChannelManager`
		// without updating any `ChannelMonitor`s as we'd fail to double-initiate the claim replay.
		// We test that here ensuring that we can reload again.
		reload_node!(nodes[3], node_d_1.encode(), &[&updated_monitor.0, &original_monitor.0], persist_d_2, chain_d_2, node_d_2);
		nodes[3].disable_monitor_completeness_assertion();
	}

	// Until the startup background events are processed (in `get_and_clear_pending_events`,
	// below), the preimage is not copied to the non-persisted monitor...
	assert!(get_monitor!(nodes[3], chan_id_persisted).get_stored_preimages().contains_key(&payment_hash));
	assert_eq!(
		get_monitor!(nodes[3], chan_id_not_persisted).get_stored_preimages().contains_key(&payment_hash),
		persist_both_monitors,
	);

	nodes[1].node.peer_disconnected(nodes[3].node.get_our_node_id());
	nodes[2].node.peer_disconnected(nodes[3].node.get_our_node_id());

	// During deserialization, we should have closed one channel and broadcast its latest
	// commitment transaction. We should also still have the original PaymentClaimable event we
	// never finished processing as well as a PaymentClaimed event regenerated when we replayed the
	// preimage onto the non-persisted monitor.
	let events = nodes[3].node.get_and_clear_pending_events();
	assert_eq!(events.len(), if persist_both_monitors { 4 } else { 3 });
	if let Event::PaymentClaimable { amount_msat: 15_000_000, .. } = events[0] { } else { panic!(); }
	if let Event::ChannelClosed { reason: ClosureReason::OutdatedChannelManager, .. } = events[1] { } else { panic!(); }
	if persist_both_monitors {
		if let Event::ChannelClosed { reason: ClosureReason::OutdatedChannelManager, .. } = events[2] { } else { panic!(); }
		if let Event::PaymentClaimed { amount_msat: 15_000_000, .. } = events[3] { } else { panic!(); }
		check_added_monitors(&nodes[3], 4);
	} else {
		if let Event::PaymentClaimed { amount_msat: 15_000_000, .. } = events[2] { } else { panic!(); }
		check_added_monitors(&nodes[3], 3);
	}

	// Now that we've processed background events, the preimage should have been copied into the
	// non-persisted monitor:
	assert!(get_monitor!(nodes[3], chan_id_persisted).get_stored_preimages().contains_key(&payment_hash));
	assert!(get_monitor!(nodes[3], chan_id_not_persisted).get_stored_preimages().contains_key(&payment_hash));

	// On restart, we should also get a duplicate PaymentClaimed event as we persisted the
	// ChannelManager prior to handling the original one.
	if let Event::PaymentClaimed { payment_hash: our_payment_hash, amount_msat: 15_000_000, .. } =
		events[if persist_both_monitors { 3 } else { 2 }]
	{
		assert_eq!(payment_hash, our_payment_hash);
	} else { panic!(); }

	assert_eq!(nodes[3].node.list_channels().len(), if persist_both_monitors { 0 } else { 1 });
	if !persist_both_monitors {
		// If one of the two channels is still live, reveal the payment preimage over it.

		nodes[3].node.peer_connected(nodes[2].node.get_our_node_id(), &msgs::Init {
			features: nodes[2].node.init_features(), networks: None, remote_network_address: None
		}, true).unwrap();
		let reestablish_1 = get_chan_reestablish_msgs!(nodes[3], nodes[2]);
		nodes[2].node.peer_connected(nodes[3].node.get_our_node_id(), &msgs::Init {
			features: nodes[3].node.init_features(), networks: None, remote_network_address: None
		}, false).unwrap();
		let reestablish_2 = get_chan_reestablish_msgs!(nodes[2], nodes[3]);

		nodes[2].node.handle_channel_reestablish(nodes[3].node.get_our_node_id(), &reestablish_1[0]);
		get_event_msg!(nodes[2], MessageSendEvent::SendChannelUpdate, nodes[3].node.get_our_node_id());
		assert!(nodes[2].node.get_and_clear_pending_msg_events().is_empty());

		nodes[3].node.handle_channel_reestablish(nodes[2].node.get_our_node_id(), &reestablish_2[0]);

		// Once we call `get_and_clear_pending_msg_events` the holding cell is cleared and the HTLC
		// claim should fly.
		let mut ds_msgs = nodes[3].node.get_and_clear_pending_msg_events();
		check_added_monitors(&nodes[3], 1);
		assert_eq!(ds_msgs.len(), 2);
		if let MessageSendEvent::SendChannelUpdate { .. } = ds_msgs[0] {} else { panic!(); }

		let mut cs_updates = match ds_msgs.remove(1) {
			MessageSendEvent::UpdateHTLCs { mut updates, .. } => {
				let mut fulfill = updates.update_fulfill_htlcs.remove(0);
				nodes[2].node.handle_update_fulfill_htlc(nodes[3].node.get_our_node_id(), fulfill);
				check_added_monitors(&nodes[2], 1);
				let cs_updates = get_htlc_update_msgs(&nodes[2], &nodes[0].node.get_our_node_id());
				expect_payment_forwarded!(nodes[2], nodes[0], nodes[3], Some(1000), false, false);
				do_commitment_signed_dance(&nodes[2], &nodes[3], &updates.commitment_signed, false, true);
				cs_updates
			}
			_ => panic!(),
		};

		let fulfill = cs_updates.update_fulfill_htlcs.remove(0);
		nodes[0].node.handle_update_fulfill_htlc(nodes[2].node.get_our_node_id(), fulfill);
		do_commitment_signed_dance(&nodes[0], &nodes[2], &cs_updates.commitment_signed, false, true);
		expect_payment_sent!(nodes[0], payment_preimage);

		// Ensure that the remaining channel is fully operation and not blocked (and that after a
		// cycle of commitment updates the payment preimage is ultimately pruned).
		nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
		send_payment(&nodes[0], &[&nodes[2], &nodes[3]], 100_000);
		assert!(!get_monitor!(nodes[3], chan_id_not_persisted).get_stored_preimages().contains_key(&payment_hash));
	}
}

#[test]
fn test_partial_claim_before_restart() {
	do_test_partial_claim_before_restart(false, false);
	do_test_partial_claim_before_restart(false, true);
	do_test_partial_claim_before_restart(true, false);
	do_test_partial_claim_before_restart(true, true);
}

#[test]
fn test_mpp_claim_htlc_fulfills_unblocked_on_reload() {
	let chanmon_cfgs = create_chanmon_cfgs(2);
	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;
	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
	let nodes_1_deserialized;
	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);

	// Open two independent channels between the same nodes. The payment below is large enough to
	// force the router to split it across both channels, which is what makes the MPP claim depend
	// on both ChannelMonitors durably learning the preimage.
	let chan_a = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100_000, 0);
	let chan_b = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100_000, 0);
	let chan_id_a = chan_a.2;
	let chan_id_b = chan_b.2;
	let scid_a = chan_a.0.contents.short_channel_id;
	let scid_b = chan_b.0.contents.short_channel_id;

	// Send an MPP payment to nodes[1]. `send_along_route_with_secret` leaves the payment
	// claimable but unclaimed, so nodes[1] still has both inbound HTLCs live when we start
	// manipulating monitor persistence below.
	let amt_msat = 50_000_000;
	let (route, payment_hash, payment_preimage, payment_secret) =
		get_route_and_payment_hash!(nodes[0], nodes[1], amt_msat);
	assert_eq!(route.paths.len(), 2);
	send_along_route_with_secret(
		&nodes[0], route, &[&[&nodes[1]], &[&nodes[1]]], amt_msat, payment_hash,
		payment_secret,
	);

	// Move both channels into `AWAITING_REMOTE_REVOKE` by having nodes[0] send fee updates and
	// withholding nodes[1]'s responding `commitment_signed`s. When nodes[1] later claims the
	// payment, the fulfill updates cannot be sent immediately and instead sit in each channel's
	// holding cell.
	{
		let mut fee_est = chanmon_cfgs[0].fee_estimator.sat_per_kw.lock().unwrap();
		*fee_est *= 2;
	}
	nodes[0].node.timer_tick_occurred();
	check_added_monitors(&nodes[0], 2);

	let node_0_id = nodes[0].node.get_our_node_id();
	let node_1_id = nodes[1].node.get_our_node_id();

	let fee_msgs = nodes[0].node.get_and_clear_pending_msg_events();
	assert_eq!(fee_msgs.len(), 2);
	for ev in &fee_msgs {
		match ev {
			MessageSendEvent::UpdateHTLCs { updates, .. } => {
				nodes[1].node.handle_update_fee(node_0_id, updates.update_fee.as_ref().unwrap());
				nodes[1].node.handle_commitment_signed_batch_test(
					node_0_id, &updates.commitment_signed,
				);
				check_added_monitors(&nodes[1], 1);
			},
			_ => panic!("Unexpected message: {:?}", ev),
		}
	}

	// nodes[1] responds to each fee update with a `revoke_and_ack` and a new
	// `commitment_signed`. Deliver only the `revoke_and_ack`s for now. The held
	// `commitment_signed`s are delivered after nodes[1] claims the payment, creating the blocked
	// post-claim monitor updates whose release is exercised after reload.
	let node_1_msgs = nodes[1].node.get_and_clear_pending_msg_events();
	let mut commitment_signed_msgs = Vec::new();
	for ev in &node_1_msgs {
		match ev {
			MessageSendEvent::SendRevokeAndACK { msg, .. } => {
				nodes[0].node.handle_revoke_and_ack(node_1_id, msg);
				check_added_monitors(&nodes[0], 1);
			},
			MessageSendEvent::UpdateHTLCs { updates, .. } => {
				commitment_signed_msgs.push(updates.commitment_signed.clone());
			},
			_ => panic!("Unexpected message: {:?}", ev),
		}
	}

	let node_0_msgs = nodes[0].node.get_and_clear_pending_msg_events();
	for ev in &node_0_msgs {
		match ev {
			MessageSendEvent::SendRevokeAndACK { msg, .. } => {
				nodes[1].node.handle_revoke_and_ack(node_0_id, msg);
				check_added_monitors(&nodes[1], 1);
			},
			_ => panic!("Unexpected message: {:?}", ev),
		}
	}

	// Snapshot channel B before the claim. The in-memory ChainMonitor applies updates even when
	// the persister returns `InProgress`, so taking this snapshot after the claim would not model a
	// crash between two separate monitor writes.
	let mon_b_serialized = get_monitor!(nodes[1], chan_id_b).encode();

	// Make both preimage monitor writes asynchronous. `claim_funds` attaches an in-memory MPP RAA
	// blocker so neither channel can release later monitor updates until all channels have the
	// preimage durably persisted.
	chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
	chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
	nodes[1].node.claim_funds(payment_preimage);
	check_added_monitors(&nodes[1], 2);

	// Complete only channel A's preimage update. Channel B will be reloaded from the stale snapshot
	// above, simulating a crash where one monitor write completed and the other did not.
	let (update_id_a, _) = get_latest_mon_update_id(&nodes[1], chan_id_a);
	nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(chan_id_a, update_id_a);

	// Now finish the fee-update commitment dance we held back. nodes[1] receives nodes[0]'s
	// `revoke_and_ack`s while the MPP RAA blocker is still in place, so the resulting monitor
	// updates are blocked behind state that is not serialized in the ChannelManager.
	for commitment_signed in &commitment_signed_msgs {
		nodes[0].node.handle_commitment_signed_batch_test(node_1_id, commitment_signed);
		check_added_monitors(&nodes[0], 1);
	}
	let node_0_msgs = nodes[0].node.get_and_clear_pending_msg_events();
	for ev in &node_0_msgs {
		match ev {
			MessageSendEvent::SendRevokeAndACK { msg, .. } => {
				nodes[1].node.handle_revoke_and_ack(node_0_id, msg);
				check_added_monitors(&nodes[1], 0);
			},
			_ => panic!("Unexpected message: {:?}", ev),
		}
	}

	// Persist the ChannelManager after the blocked post-claim monitor updates have been recorded.
	// Reload with channel A's up-to-date monitor and channel B's stale monitor. The preimage update
	// for B is replayed during reload, putting both channels' preimages on disk. The remaining state
	// under test is the blocked post-claim `revoke_and_ack` monitor updates after the in-memory MPP
	// RAA blocker that created them is gone.
	let node_1_serialized = nodes[1].node.encode();
	let mon_a_serialized = get_monitor!(nodes[1], chan_id_a).encode();

	nodes[0].node.peer_disconnected(node_1_id);
	reload_node!(
		nodes[1],
		node_1_serialized,
		&[&mon_a_serialized, &mon_b_serialized],
		persister,
		new_chain_monitor,
		nodes_1_deserialized
	);

	// Reconnect both peers by manually exchanging `channel_reestablish`s. This avoids relying on a
	// more general reconnect helper while the channels intentionally have asymmetric monitor state.
	let node_1_id = nodes[1].node.get_our_node_id();
	nodes[0].node.peer_connected(node_1_id, &msgs::Init {
		features: nodes[1].node.init_features(), networks: None, remote_network_address: None,
	}, true).unwrap();
	nodes[1].node.peer_connected(node_0_id, &msgs::Init {
		features: nodes[0].node.init_features(), networks: None, remote_network_address: None,
	}, false).unwrap();

	let reestablish_0 = nodes[0].node.get_and_clear_pending_msg_events();
	let reestablish_1 = nodes[1].node.get_and_clear_pending_msg_events();
	let mut reestablish_0_chan_ids = Vec::new();
	let mut reestablish_1_chan_ids = Vec::new();
	for ev in &reestablish_1 {
		match ev {
			MessageSendEvent::SendChannelReestablish { node_id, msg } => {
				assert_eq!(*node_id, node_0_id);
				reestablish_1_chan_ids.push(msg.channel_id);
				nodes[0].node.handle_channel_reestablish(node_1_id, msg);
			},
			_ => panic!("Unexpected message: {:?}", ev),
		}
	}
	for ev in &reestablish_0 {
		match ev {
			MessageSendEvent::SendChannelReestablish { node_id, msg } => {
				assert_eq!(*node_id, node_1_id);
				reestablish_0_chan_ids.push(msg.channel_id);
				nodes[1].node.handle_channel_reestablish(node_0_id, msg);
			},
			_ => panic!("Unexpected message: {:?}", ev),
		}
	}
	assert_eq!(reestablish_0_chan_ids.len(), 2);
	assert!(reestablish_0_chan_ids.contains(&chan_id_a));
	assert!(reestablish_0_chan_ids.contains(&chan_id_b));
	assert_eq!(reestablish_1_chan_ids.len(), 2);
	assert!(reestablish_1_chan_ids.contains(&chan_id_a));
	assert!(reestablish_1_chan_ids.contains(&chan_id_b));
	// Only nodes[1] was reloaded with stale monitor state. nodes[0] responds to the
	// `channel_reestablish`s without touching its monitors. nodes[1] applies the replayed channel B
	// preimage update, releases channel A's held RAA update, and frees channel A's held fulfill
	// during startup processing.
	check_added_monitors(&nodes[0], 0);
	check_added_monitors(&nodes[1], 3);

	// The first message batch after reconnect contains channel updates from both nodes. nodes[1]
	// also sends the channel A fulfill that startup processing released from the holding cell.
	let restart_msgs_0 = nodes[0].node.get_and_clear_pending_msg_events();
	let restart_msgs_1 = nodes[1].node.get_and_clear_pending_msg_events();
	let mut restart_scids_0 = Vec::new();
	let mut restart_scids_1 = Vec::new();
	let mut startup_fulfill_chan_ids = Vec::new();
	for ev in &restart_msgs_0 {
		match ev {
			MessageSendEvent::SendChannelUpdate { node_id, msg } => {
				assert_eq!(*node_id, node_1_id);
				restart_scids_0.push(msg.contents.short_channel_id);
			},
			_ => panic!("Unexpected restart message from node 0: {:?}", ev),
		}
	}
	for ev in &restart_msgs_1 {
		match ev {
			MessageSendEvent::SendChannelUpdate { node_id, msg } => {
				assert_eq!(*node_id, node_0_id);
				restart_scids_1.push(msg.contents.short_channel_id);
			},
			MessageSendEvent::UpdateHTLCs { node_id, channel_id, updates } => {
				assert_eq!(*node_id, node_0_id);
				startup_fulfill_chan_ids.push(*channel_id);
				assert_eq!(updates.update_fulfill_htlcs.len(), 1);
				assert!(updates.update_add_htlcs.is_empty());
				assert!(updates.update_fail_htlcs.is_empty());
				assert!(updates.update_fail_malformed_htlcs.is_empty());
				assert!(updates.update_fee.is_none());
				for fulfill in &updates.update_fulfill_htlcs {
					nodes[0].node.handle_update_fulfill_htlc(node_1_id, fulfill.clone());
				}
				// Complete the standard commitment handshake for the released fulfill. The helper
				// checks nodes[0]'s incoming commitment monitor update, nodes[1]'s response monitor
				// updates, and nodes[0]'s held final monitor update.
				do_commitment_signed_dance(
					&nodes[0], &nodes[1], &updates.commitment_signed, false, false,
				);
			},
			_ => panic!("Unexpected restart message from node 1: {:?}", ev),
		}
	}
	assert_eq!(restart_scids_0.len(), 2);
	assert!(restart_scids_0.contains(&scid_a));
	assert!(restart_scids_0.contains(&scid_b));
	assert_eq!(restart_scids_1.len(), 2);
	assert!(restart_scids_1.contains(&scid_a));
	assert!(restart_scids_1.contains(&scid_b));
	assert_eq!(startup_fulfill_chan_ids, vec![chan_id_a]);
	assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
	check_added_monitors(&nodes[0], 0);
	check_added_monitors(&nodes[1], 0);

	// Receiving the startup-released fulfill gives nodes[0] the payment preimage. That is enough to
	// emit `PaymentSent`, even though channel B's path-level success still needs its own fulfill.
	let startup_payment_events = nodes[0].node.get_and_clear_pending_events();
	assert_eq!(startup_payment_events.len(), 2);
	let mut saw_startup_payment_sent = false;
	let mut startup_success_scids = Vec::new();
	for ev in &startup_payment_events {
		match ev {
			Event::PaymentSent {
				payment_preimage: sent_preimage,
				payment_hash: sent_hash,
				amount_msat: sent_amount,
				fee_paid_msat,
				..
			} => {
				assert_eq!(*sent_preimage, payment_preimage);
				assert_eq!(*sent_hash, payment_hash);
				assert_eq!(*sent_amount, Some(amt_msat));
				assert_eq!(*fee_paid_msat, Some(0));
				saw_startup_payment_sent = true;
			},
			Event::PaymentPathSuccessful { payment_hash: Some(path_hash), path, .. } => {
				assert_eq!(*path_hash, payment_hash);
				assert_eq!(path.hops.len(), 1);
				startup_success_scids.push(path.hops[0].short_channel_id);
			},
			_ => panic!("Unexpected startup payment event: {:?}", ev),
		}
	}
	assert!(saw_startup_payment_sent);
	assert_eq!(startup_success_scids, vec![scid_a]);

	// Handling the claim event runs the event-completion action that releases the remaining
	// RAA-blocked monitor update. The startup unblock path already released channel A, so channel B
	// is the only fulfill that should be emitted here.
	let claim_events = nodes[1].node.get_and_clear_pending_events();
	assert_eq!(claim_events.len(), 1);
	match &claim_events[0] {
		Event::PaymentClaimed { payment_hash: claimed_hash, amount_msat, htlcs, .. } => {
			assert_eq!(*claimed_hash, payment_hash);
			assert_eq!(*amount_msat, amt_msat);
			assert_eq!(htlcs.len(), 2);
		},
		_ => panic!("Unexpected event: {:?}", claim_events[0]),
	}
	// The `PaymentSent` event above releases the monitor update that nodes[0] held after the final
	// channel A startup revocation.
	check_added_monitors(&nodes[0], 1);
	// Handling `PaymentClaimed` releases channel B's held revocation update and then the fulfill
	// that was waiting behind it.
	check_added_monitors(&nodes[1], 2);

	// Channel A's fulfill was already sent during startup. The `PaymentClaimed` completion action
	// now frees channel B's held fulfill, and no other HTLC update should be bundled with it.
	let fulfill_msgs = nodes[1].node.get_and_clear_pending_msg_events();
	assert_eq!(fulfill_msgs.len(), 1);
	match &fulfill_msgs[0] {
		MessageSendEvent::UpdateHTLCs { node_id, channel_id, updates } => {
			assert_eq!(*node_id, node_0_id);
			assert_eq!(*channel_id, chan_id_b);
			assert_eq!(updates.update_fulfill_htlcs.len(), 1);
			assert!(updates.update_add_htlcs.is_empty());
			assert!(updates.update_fail_htlcs.is_empty());
			assert!(updates.update_fail_malformed_htlcs.is_empty());
			assert!(updates.update_fee.is_none());
			for fulfill in &updates.update_fulfill_htlcs {
				nodes[0].node.handle_update_fulfill_htlc(node_1_id, fulfill.clone());
			}
			// Complete the same commitment handshake for channel B. Here nodes[0]'s final monitor
			// update is persisted immediately because `PaymentSent` already ran for channel A.
			do_commitment_signed_dance(
				&nodes[0], &nodes[1], &updates.commitment_signed, false, false,
			);
		},
		_ => panic!("Unexpected fulfill message: {:?}", fulfill_msgs[0]),
	}
	check_added_monitors(&nodes[1], 0);
	assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());

	let final_payment_events = nodes[0].node.get_and_clear_pending_events();
	assert_eq!(final_payment_events.len(), 1);
	match &final_payment_events[0] {
		Event::PaymentPathSuccessful { payment_hash: Some(path_hash), path, .. } => {
			assert_eq!(*path_hash, payment_hash);
			assert_eq!(path.hops.len(), 1);
			assert_eq!(path.hops[0].short_channel_id, scid_b);
		},
		_ => panic!("Unexpected final payment event: {:?}", final_payment_events[0]),
	}
	check_added_monitors(&nodes[0], 0);
	assert!(nodes[1].node.get_and_clear_pending_events().is_empty());
	check_added_monitors(&nodes[0], 0);
	check_added_monitors(&nodes[1], 0);

	// Both MPP parts should have been fulfilled back to nodes[0]. If either channel still has a
	// pending outbound HTLC, its fulfill remained stuck in nodes[1]'s holding cell after reload.
	let pending: Vec<_> = nodes[0].node.list_channels().iter()
		.filter(|channel| channel.channel_id == chan_id_a || channel.channel_id == chan_id_b)
		.filter(|channel| !channel.pending_outbound_htlcs.is_empty())
		.map(|channel| channel.channel_id)
		.collect();
	assert!(pending.is_empty(), "HTLC fulfills remained stuck on channels {:?}", pending);
}

fn do_forwarded_payment_no_manager_persistence(use_cs_commitment: bool, claim_htlc: bool, use_intercept: bool) {
	if !use_cs_commitment { assert!(!claim_htlc); }
	// If we go to forward a payment, and the ChannelMonitor persistence completes, but the
	// ChannelManager does not, we shouldn't try to forward the payment again, nor should we fail
	// it back until the ChannelMonitor decides the fate of the HTLC.
	// This was never an issue, but it may be easy to regress here going forward.
	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;

	let mut intercept_forwards_config = test_legacy_channel_config();
	intercept_forwards_config.htlc_interception_flags =
		HTLCInterceptionFlags::ToInterceptSCIDs as u8;
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, Some(intercept_forwards_config), None]);
	let nodes_1_deserialized;

	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	let chan_id_1 = create_announced_chan_between_nodes(&nodes, 0, 1).2;
	let chan_id_2 = create_announced_chan_between_nodes(&nodes, 1, 2).2;

	let intercept_scid = nodes[1].node.get_intercept_scid();

	let (mut route, payment_hash, payment_preimage, payment_secret) =
		get_route_and_payment_hash!(nodes[0], nodes[2], 1_000_000);
	if use_intercept {
		route.paths[0].hops[1].short_channel_id = intercept_scid;
	}
	let payment_id = PaymentId(nodes[0].keys_manager.backing.get_secure_random_bytes());
	let htlc_expiry = nodes[0].best_block_info().1 + TEST_FINAL_CLTV;
	nodes[0].node.send_payment_with_route(route, payment_hash,
		RecipientOnionFields::secret_only(payment_secret, 1_000_000), payment_id).unwrap();
	check_added_monitors(&nodes[0], 1);

	let payment_event = SendEvent::from_node(&nodes[0]);
	nodes[1].node.handle_update_add_htlc(nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
	do_commitment_signed_dance(&nodes[1], &nodes[0], &payment_event.commitment_msg, false, false);

	// Store the `ChannelManager` before handling the `HTLCIntercepted` events, expecting the event
	// (and the HTLC itself) to be missing on reload even though its present when we serialized.
	let node_encoded = nodes[1].node.encode();

	expect_htlc_failure_conditions(nodes[1].node.get_and_clear_pending_events(), &[]);

	let mut intercept_id = None;
	let mut expected_outbound_amount_msat = None;
	if use_intercept {
		nodes[1].node.test_process_pending_update_add_htlcs();
		let events = nodes[1].node.get_and_clear_pending_events();
		assert_eq!(events.len(), 1);
		match events[0] {
			Event::HTLCIntercepted { intercept_id: ev_id, expected_outbound_amount_msat: ev_amt, .. } => {
				intercept_id = Some(ev_id);
				expected_outbound_amount_msat = Some(ev_amt);
			},
			_ => panic!()
		}
		nodes[1].node.forward_intercepted_htlc(intercept_id.unwrap(), &chan_id_2,
			nodes[2].node.get_our_node_id(), expected_outbound_amount_msat.unwrap()).unwrap();
	}

	nodes[1].node.process_pending_htlc_forwards();

	let payment_event = SendEvent::from_node(&nodes[1]);
	nodes[2].node.handle_update_add_htlc(nodes[1].node.get_our_node_id(), &payment_event.msgs[0]);
	nodes[2].node.handle_commitment_signed_batch_test(nodes[1].node.get_our_node_id(), &payment_event.commitment_msg);
	check_added_monitors(&nodes[2], 1);

	if claim_htlc {
		get_monitor!(nodes[2], chan_id_2).provide_payment_preimage_unsafe_legacy(
			&payment_hash, &payment_preimage, &nodes[2].tx_broadcaster,
			&LowerBoundedFeeEstimator(nodes[2].fee_estimator), &nodes[2].logger
		);
	}
	assert!(nodes[2].tx_broadcaster.txn_broadcasted.lock().unwrap().is_empty());

	let _ = nodes[2].node.get_and_clear_pending_msg_events();
	let message = "Channel force-closed".to_owned();

	nodes[2]
		.node
		.force_close_broadcasting_latest_txn(&chan_id_2, &nodes[1].node.get_our_node_id(), message.clone())
		.unwrap();
	let cs_commitment_tx = nodes[2].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
	assert_eq!(cs_commitment_tx.len(), if claim_htlc { 2 } else { 1 });

	check_added_monitors(&nodes[2], 1);
	let reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
	check_closed_event(&nodes[2], 1, reason, &[nodes[1].node.get_our_node_id()], 100000);
	check_closed_broadcast(&nodes[2], 1, true);

	let chan_0_monitor_serialized = get_monitor!(nodes[1], chan_id_1).encode();
	let chan_1_monitor_serialized = get_monitor!(nodes[1], chan_id_2).encode();
	reload_node!(nodes[1], node_encoded, &[&chan_0_monitor_serialized, &chan_1_monitor_serialized], persister, new_chain_monitor, nodes_1_deserialized);

	// Note that this checks that this is the only event on nodes[1], implying the
	// `HTLCIntercepted` event has been removed in the `use_intercept` case.
	check_closed_event(&nodes[1], 1, ClosureReason::OutdatedChannelManager, &[nodes[2].node.get_our_node_id()], 100000);

	if use_intercept {
		// Attempt to forward the HTLC back out over nodes[1]' still-open channel, ensuring we get
		// a intercept-doesn't-exist error.
		let forward_err = nodes[1].node.forward_intercepted_htlc(intercept_id.unwrap(), &chan_id_1,
			nodes[0].node.get_our_node_id(), expected_outbound_amount_msat.unwrap()).unwrap_err();
		assert_eq!(forward_err, APIError::APIMisuseError {
			err: format!("Payment with intercept id {} not found", log_bytes!(intercept_id.unwrap().0))
		});
	}

	nodes[1].node.timer_tick_occurred();
	let bs_commitment_tx = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
	assert_eq!(bs_commitment_tx.len(), 1);
	check_added_monitors(&nodes[1], 1);

	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[1]));

	if use_cs_commitment {
		// If we confirm a commitment transaction that has the HTLC on-chain, nodes[1] should wait
		// for an HTLC-spending transaction before it does anything with the HTLC upstream.
		confirm_transaction(&nodes[1], &cs_commitment_tx[0]);
		assert!(nodes[1].node.get_and_clear_pending_events().is_empty());
		assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());

		if claim_htlc {
			confirm_transaction(&nodes[1], &cs_commitment_tx[1]);
		} else {
			connect_blocks(&nodes[1], htlc_expiry - nodes[1].best_block_info().1 + 1);
			let mut txn = nodes[1].tx_broadcaster.txn_broadcast();
			assert_eq!(txn.len(), if nodes[1].connect_style.borrow().updates_best_block_first() { 2 } else { 1 });
			let bs_htlc_timeout_tx = txn.pop().unwrap();
			confirm_transaction(&nodes[1], &bs_htlc_timeout_tx);
		}
	} else {
		confirm_transaction(&nodes[1], &bs_commitment_tx[0]);
	}

	if !claim_htlc {
		expect_and_process_pending_htlcs_and_htlc_handling_failed(
			&nodes[1],
			&[HTLCHandlingFailureType::Forward { node_id: Some(nodes[2].node.get_our_node_id()), channel_id: chan_id_2 }]
		);
	} else {
		expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], Some(1000), false, true);
	}
	check_added_monitors(&nodes[1], 1);

	let mut update = get_htlc_update_msgs(&nodes[1], &nodes[0].node.get_our_node_id());
	if claim_htlc {
		nodes[0].node.handle_update_fulfill_htlc(nodes[1].node.get_our_node_id(), update.update_fulfill_htlcs.remove(0));
	} else {
		nodes[0].node.handle_update_fail_htlc(nodes[1].node.get_our_node_id(), &update.update_fail_htlcs[0]);
	}
	do_commitment_signed_dance(&nodes[0], &nodes[1], &update.commitment_signed, false, false);

	if claim_htlc {
		expect_payment_sent!(nodes[0], payment_preimage);
	} else {
		expect_payment_failed!(nodes[0], payment_hash, false);
	}
}

#[test]
fn forwarded_payment_no_manager_persistence() {
	do_forwarded_payment_no_manager_persistence(true, true, false);
	do_forwarded_payment_no_manager_persistence(true, false, false);
	do_forwarded_payment_no_manager_persistence(false, false, false);
}

#[test]
fn intercepted_payment_no_manager_persistence() {
	do_forwarded_payment_no_manager_persistence(true, true, true);
	do_forwarded_payment_no_manager_persistence(true, false, true);
	do_forwarded_payment_no_manager_persistence(false, false, true);
}

#[test]
fn removed_payment_no_manager_persistence() {
	// If an HTLC is failed to us on a channel, and the ChannelMonitor persistence completes, but
	// the corresponding ChannelManager persistence does not, we need to ensure that the HTLC is
	// still failed back to the previous hop even though the ChannelMonitor now no longer is aware
	// of the HTLC. This was previously broken as no attempt was made to figure out which HTLCs
	// were left dangling when a channel was force-closed due to a stale ChannelManager.
	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;

	let legacy_cfg = test_legacy_channel_config();
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[Some(legacy_cfg.clone()), Some(legacy_cfg.clone()), Some(legacy_cfg)]);
	let nodes_1_deserialized;

	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	let chan_id_1 = create_announced_chan_between_nodes(&nodes, 0, 1).2;
	let chan_id_2 = create_announced_chan_between_nodes(&nodes, 1, 2).2;

	let (_, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000);

	let node_encoded = nodes[1].node.encode();

	nodes[2].node.fail_htlc_backwards(&payment_hash);
	expect_and_process_pending_htlcs_and_htlc_handling_failed(
		&nodes[2],
		&[HTLCHandlingFailureType::Receive { payment_hash }]
	);
	check_added_monitors(&nodes[2], 1);
	let events = nodes[2].node.get_and_clear_pending_msg_events();
	assert_eq!(events.len(), 1);
	match &events[0] {
		MessageSendEvent::UpdateHTLCs { updates: msgs::CommitmentUpdate { update_fail_htlcs, commitment_signed, .. }, .. } => {
			nodes[1].node.handle_update_fail_htlc(nodes[2].node.get_our_node_id(), &update_fail_htlcs[0]);
			do_commitment_signed_dance(&nodes[1], &nodes[2], &commitment_signed, false, false);
		},
		_ => panic!("Unexpected event"),
	}

	let chan_0_monitor_serialized = get_monitor!(nodes[1], chan_id_1).encode();
	let chan_1_monitor_serialized = get_monitor!(nodes[1], chan_id_2).encode();
	reload_node!(nodes[1], node_encoded, &[&chan_0_monitor_serialized, &chan_1_monitor_serialized], persister, new_chain_monitor, nodes_1_deserialized);

	match nodes[1].node.pop_pending_event().unwrap() {
		Event::ChannelClosed { ref reason, .. } => {
			assert_eq!(*reason, ClosureReason::OutdatedChannelManager);
		},
		_ => panic!("Unexpected event"),
	}

	nodes[1].node.test_process_background_events();
	check_added_monitors(&nodes[1], 1);

	// Now that the ChannelManager has force-closed the channel which had the HTLC removed, it is
	// now forgotten everywhere. The ChannelManager should have, as a side-effect of reload,
	// learned that the HTLC is gone from the ChannelMonitor and added it to the to-fail-back set.
	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[1]));

	expect_and_process_pending_htlcs_and_htlc_handling_failed(
		&nodes[1],
		&[HTLCHandlingFailureType::Forward { node_id: Some(nodes[2].node.get_our_node_id()), channel_id: chan_id_2 }]
	);
	check_added_monitors(&nodes[1], 1);
	let events = nodes[1].node.get_and_clear_pending_msg_events();
	assert_eq!(events.len(), 1);
	match &events[0] {
		MessageSendEvent::UpdateHTLCs { updates: msgs::CommitmentUpdate { update_fail_htlcs, commitment_signed, .. }, .. } => {
			nodes[0].node.handle_update_fail_htlc(nodes[1].node.get_our_node_id(), &update_fail_htlcs[0]);
			do_commitment_signed_dance(&nodes[0], &nodes[1], &commitment_signed, false, false);
		},
		_ => panic!("Unexpected event"),
	}

	expect_payment_failed!(nodes[0], payment_hash, false);
}

#[test]
fn manager_persisted_pre_outbound_edge_forward() {
	do_manager_persisted_pre_outbound_edge_forward(false);
}

#[test]
fn manager_persisted_pre_outbound_edge_intercept_forward() {
	do_manager_persisted_pre_outbound_edge_forward(true);
}

fn do_manager_persisted_pre_outbound_edge_forward(intercept_htlc: bool) {
	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;
	let mut intercept_forwards_config = test_default_channel_config();
	intercept_forwards_config.htlc_interception_flags =
		HTLCInterceptionFlags::ToInterceptSCIDs as u8;
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, Some(intercept_forwards_config), None]);
	let nodes_1_deserialized;
	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	let chan_id_1 = create_announced_chan_between_nodes(&nodes, 0, 1).2;
	let chan_id_2 = create_announced_chan_between_nodes(&nodes, 1, 2).2;

	// Lock in the HTLC from node_a <> node_b.
	let amt_msat = 5000;
	let (mut route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[2], amt_msat);
	if intercept_htlc {
		route.paths[0].hops[1].short_channel_id = nodes[1].node.get_intercept_scid();
	}
	nodes[0].node.send_payment_with_route(route, payment_hash, RecipientOnionFields::secret_only(payment_secret, amt_msat), PaymentId(payment_hash.0)).unwrap();
	check_added_monitors(&nodes[0], 1);
	let updates = get_htlc_update_msgs(&nodes[0], &nodes[1].node.get_our_node_id());
	nodes[1].node.handle_update_add_htlc(nodes[0].node.get_our_node_id(), &updates.update_add_htlcs[0]);
	do_commitment_signed_dance(&nodes[1], &nodes[0], &updates.commitment_signed, false, false);
	// While an inbound HTLC is committed in a channel but not yet forwarded, we store its onion in
	// the `Channel` in case we need to remember it on restart. Once it's irrevocably forwarded to the
	// outbound edge, we can prune it on the inbound edge.
	assert_eq!(
		nodes[1].node.test_get_inbound_committed_htlcs_with_onion(nodes[0].node.get_our_node_id(), chan_id_1),
		1
	);

	// Decode the HTLC onion but don't forward it to the next hop, such that the HTLC ends up in
	// `ChannelManager::forward_htlcs` or `ChannelManager::pending_intercepted_htlcs`.
	nodes[1].node.test_process_pending_update_add_htlcs();

	// Disconnect peers and reload the forwarding node_b.
	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	nodes[2].node.peer_disconnected(nodes[1].node.get_our_node_id());

	let node_b_encoded = nodes[1].node.encode();

	let chan_0_monitor_serialized = get_monitor!(nodes[1], chan_id_1).encode();
	let chan_1_monitor_serialized = get_monitor!(nodes[1], chan_id_2).encode();
	reload_node!(nodes[1], node_b_encoded, &[&chan_0_monitor_serialized, &chan_1_monitor_serialized], persister, new_chain_monitor, nodes_1_deserialized);

	reconnect_nodes(ReconnectArgs::new(&nodes[1], &nodes[0]));
	let mut args_b_c = ReconnectArgs::new(&nodes[1], &nodes[2]);
	args_b_c.send_channel_ready = (true, true);
	args_b_c.send_announcement_sigs = (true, true);
	reconnect_nodes(args_b_c);

	// Before an inbound HTLC is irrevocably forwarded, its onion should still be persisted within the
	// inbound edge channel.
	assert_eq!(
		nodes[1].node.test_get_inbound_committed_htlcs_with_onion(nodes[0].node.get_our_node_id(), chan_id_1),
		1
	);

	// Forward the HTLC and ensure we can claim it post-reload.
	nodes[1].node.process_pending_htlc_forwards();

	if intercept_htlc {
		let events = nodes[1].node.get_and_clear_pending_events();
		assert_eq!(events.len(), 1);
		let (intercept_id, expected_outbound_amt_msat) = match events[0] {
			Event::HTLCIntercepted { intercept_id, expected_outbound_amount_msat, .. } => {
				(intercept_id, expected_outbound_amount_msat)
			},
			_ => panic!()
		};
		nodes[1].node.forward_intercepted_htlc(intercept_id, &chan_id_2,
			nodes[2].node.get_our_node_id(), expected_outbound_amt_msat).unwrap();
		nodes[1].node.process_pending_htlc_forwards();
	}
	check_added_monitors(&nodes[1], 1);

	let updates = get_htlc_update_msgs(&nodes[1], &nodes[2].node.get_our_node_id());
	nodes[2].node.handle_update_add_htlc(nodes[1].node.get_our_node_id(), &updates.update_add_htlcs[0]);
	do_commitment_signed_dance(&nodes[2], &nodes[1], &updates.commitment_signed, false, false);
	expect_and_process_pending_htlcs(&nodes[2], false);
	// After an inbound HTLC is irrevocably forwarded, its onion should be pruned within the inbound
	// edge channel.
	assert_eq!(
		nodes[1].node.test_get_inbound_committed_htlcs_with_onion(nodes[0].node.get_our_node_id(), chan_id_1),
		0
	);

	expect_payment_claimable!(nodes[2], payment_hash, payment_secret, amt_msat, None, nodes[2].node.get_our_node_id());
	let path: &[&[_]] = &[&[&nodes[1], &nodes[2]]];
	do_claim_payment_along_route(ClaimAlongRouteArgs::new(&nodes[0], path, payment_preimage));
	expect_payment_sent(&nodes[0], payment_preimage, None, true, true);
}

#[test]
fn test_manager_persisted_post_outbound_edge_forward() {
	// Test that we will not double-forward an HTLC after restart if it has already been forwarded to
	// the outbound edge, which was previously broken.
	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
	let nodes_1_deserialized;
	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	let chan_id_1 = create_announced_chan_between_nodes(&nodes, 0, 1).2;
	let chan_id_2 = create_announced_chan_between_nodes(&nodes, 1, 2).2;

	// Lock in the HTLC from node_a <> node_b.
	let amt_msat = 5000;
	let (mut route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[2], amt_msat);
	nodes[0].node.send_payment_with_route(route, payment_hash, RecipientOnionFields::secret_only(payment_secret, amt_msat), PaymentId(payment_hash.0)).unwrap();
	check_added_monitors(&nodes[0], 1);
	let updates = get_htlc_update_msgs(&nodes[0], &nodes[1].node.get_our_node_id());
	nodes[1].node.handle_update_add_htlc(nodes[0].node.get_our_node_id(), &updates.update_add_htlcs[0]);
	do_commitment_signed_dance(&nodes[1], &nodes[0], &updates.commitment_signed, false, false);

	// Add the HTLC to the outbound edge, node_b <> node_c.
	nodes[1].node.process_pending_htlc_forwards();
	check_added_monitors(&nodes[1], 1);

	// Disconnect peers and reload the forwarding node_b.
	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	nodes[2].node.peer_disconnected(nodes[1].node.get_our_node_id());

	let node_b_encoded = nodes[1].node.encode();
	let chan_0_monitor_serialized = get_monitor!(nodes[1], chan_id_1).encode();
	let chan_1_monitor_serialized = get_monitor!(nodes[1], chan_id_2).encode();
	reload_node!(nodes[1], node_b_encoded, &[&chan_0_monitor_serialized, &chan_1_monitor_serialized], persister, new_chain_monitor, nodes_1_deserialized);

	reconnect_nodes(ReconnectArgs::new(&nodes[1], &nodes[0]));
	let mut args_b_c = ReconnectArgs::new(&nodes[1], &nodes[2]);
	args_b_c.send_channel_ready = (true, true);
	args_b_c.send_announcement_sigs = (true, true);
	args_b_c.pending_htlc_adds = (0, 1);
	// While reconnecting, we re-send node_b's outbound update_add and commit the HTLC to the b<>c
	// channel.
	reconnect_nodes(args_b_c);

	// Ensure node_b won't double-forward the outbound HTLC (this was previously broken).
	nodes[1].node.process_pending_htlc_forwards();
	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());

	// Claim the HTLC backwards to node_a.
	expect_and_process_pending_htlcs(&nodes[2], false);
	expect_payment_claimable!(nodes[2], payment_hash, payment_secret, amt_msat, None, nodes[2].node.get_our_node_id());
	let path: &[&[_]] = &[&[&nodes[1], &nodes[2]]];
	do_claim_payment_along_route(ClaimAlongRouteArgs::new(&nodes[0], path, payment_preimage));
	expect_payment_sent(&nodes[0], payment_preimage, None, true, true);
}

#[test]
fn test_manager_persisted_post_outbound_edge_holding_cell() {
	// Test that we will not double-forward an HTLC after restart if it is already in the outbound
	// edge's holding cell, which was previously broken.
	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
	let nodes_1_deserialized;
	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	let chan_id_1 = create_announced_chan_between_nodes(&nodes, 0, 1).2;
	let chan_id_2 = create_announced_chan_between_nodes(&nodes, 1, 2).2;
	send_payment(&nodes[0], &[&nodes[1], &nodes[2]], 5000000);

	// Lock in the HTLC from node_a <> node_b.
	let amt_msat = 1000;
	let (route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[2], amt_msat);
	let onion = RecipientOnionFields::secret_only(payment_secret, amt_msat);
	nodes[0].node.send_payment_with_route(route, payment_hash, onion, PaymentId(payment_hash.0)).unwrap();
	check_added_monitors(&nodes[0], 1);
	let updates = get_htlc_update_msgs(&nodes[0], &nodes[1].node.get_our_node_id());
	nodes[1].node.handle_update_add_htlc(nodes[0].node.get_our_node_id(), &updates.update_add_htlcs[0]);
	do_commitment_signed_dance(&nodes[1], &nodes[0], &updates.commitment_signed, false, false);

	// Send a 2nd HTLC node_c -> node_b, to force the first HTLC into the holding cell.
	chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
	let (route_2, payment_hash_2, payment_preimage_2, payment_secret_2) = get_route_and_payment_hash!(nodes[2], nodes[1], amt_msat);
	let onion = RecipientOnionFields::secret_only(payment_secret_2, amt_msat);
	nodes[2].node.send_payment_with_route(route_2, payment_hash_2, onion, PaymentId(payment_hash_2.0)).unwrap();
	let send_event =
		SendEvent::from_event(nodes[2].node.get_and_clear_pending_msg_events().remove(0));
	nodes[1].node.handle_update_add_htlc(nodes[2].node.get_our_node_id(), &send_event.msgs[0]);
	nodes[1].node.handle_commitment_signed_batch_test(nodes[2].node.get_our_node_id(), &send_event.commitment_msg);
	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
	check_added_monitors(&nodes[1], 1);
	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());

	// Add the HTLC to the outbound edge, node_b <> node_c. Force the outbound HTLC into the b<>c
	// holding cell.
	nodes[1].node.process_pending_htlc_forwards();
	check_added_monitors(&nodes[1], 0);
	assert_eq!(
		nodes[1].node.test_holding_cell_outbound_htlc_forwards_count(nodes[2].node.get_our_node_id(), chan_id_2),
		1
	);

	// Disconnect peers and reload the forwarding node_b.
	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	nodes[2].node.peer_disconnected(nodes[1].node.get_our_node_id());

	let node_b_encoded = nodes[1].node.encode();
	let chan_0_monitor_serialized = get_monitor!(nodes[1], chan_id_1).encode();
	let chan_1_monitor_serialized = get_monitor!(nodes[1], chan_id_2).encode();
	reload_node!(nodes[1], node_b_encoded, &[&chan_0_monitor_serialized, &chan_1_monitor_serialized], persister, new_chain_monitor, nodes_1_deserialized);

	chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
	let (latest_update, _) = get_latest_mon_update_id(&nodes[1], chan_id_2);
	nodes[1].chain_monitor.chain_monitor.force_channel_monitor_updated(chan_id_2, latest_update);

	reconnect_nodes(ReconnectArgs::new(&nodes[1], &nodes[0]));

	// Reconnect b<>c. Node_b has pending RAA + commitment_signed from the incomplete c->b
	// commitment dance, plus an HTLC in the holding cell that will be released after the dance.
	let mut reconnect_args = ReconnectArgs::new(&nodes[1], &nodes[2]);
	reconnect_args.pending_raa = (false, true);
	reconnect_args.pending_responding_commitment_signed = (false, true);
	// Node_c needs a monitor update to catch up after processing node_b's reestablish.
	reconnect_args.expect_renegotiated_funding_locked_monitor_update = (false, true);
	// The holding cell HTLC will be released after the commitment dance - handle it below.
	reconnect_args.allow_post_commitment_dance_msgs = (false, true);
	reconnect_nodes(reconnect_args);

	// The holding cell HTLC was released during the reconnect. Complete its commitment dance.
	let holding_cell_htlc_msgs = nodes[1].node.get_and_clear_pending_msg_events();
	assert_eq!(holding_cell_htlc_msgs.len(), 1);
	match &holding_cell_htlc_msgs[0] {
		MessageSendEvent::UpdateHTLCs { node_id, updates, .. } => {
			assert_eq!(*node_id, nodes[2].node.get_our_node_id());
			assert_eq!(updates.update_add_htlcs.len(), 1);
			nodes[2].node.handle_update_add_htlc(nodes[1].node.get_our_node_id(), &updates.update_add_htlcs[0]);
			do_commitment_signed_dance(&nodes[2], &nodes[1], &updates.commitment_signed, false, false);
		}
		_ => panic!("Unexpected message: {:?}", holding_cell_htlc_msgs[0]),
	}

	// Ensure node_b won't double-forward the outbound HTLC (this was previously broken).
	nodes[1].node.process_pending_htlc_forwards();
	let msgs = nodes[1].node.get_and_clear_pending_msg_events();
	assert!(msgs.is_empty(), "Expected 0 messages, got {:?}", msgs);

	// The a->b->c HTLC is now committed on node_c. The c->b HTLC is committed on node_b.
	// Both payments should now be claimable.
	expect_and_process_pending_htlcs(&nodes[2], false);
	expect_payment_claimable!(nodes[2], payment_hash, payment_secret, amt_msat, None, nodes[2].node.get_our_node_id());
	expect_payment_claimable!(nodes[1], payment_hash_2, payment_secret_2, amt_msat, None, nodes[1].node.get_our_node_id());

	// Claim the a->b->c payment on node_c.
	let path: &[&[_]] = &[&[&nodes[1], &nodes[2]]];
	do_claim_payment_along_route(ClaimAlongRouteArgs::new(&nodes[0], path, payment_preimage));
	expect_payment_sent(&nodes[0], payment_preimage, None, true, true);

	// Claim the c->b payment on node_b.
	nodes[1].node.claim_funds(payment_preimage_2);
	expect_payment_claimed!(nodes[1], payment_hash_2, amt_msat);
	check_added_monitors(&nodes[1], 1);
	let mut update = get_htlc_update_msgs(&nodes[1], &nodes[2].node.get_our_node_id());
	nodes[2].node.handle_update_fulfill_htlc(nodes[1].node.get_our_node_id(), update.update_fulfill_htlcs.remove(0));
	do_commitment_signed_dance(&nodes[2], &nodes[1], &update.commitment_signed, false, false);
	expect_payment_sent(&nodes[2], payment_preimage_2, None, true, true);
}

#[test]
fn test_reload_partial_funding_batch() {
	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let new_persister;
	let new_chain_monitor;

	let legacy_cfg = test_legacy_channel_config();
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[Some(legacy_cfg.clone()), Some(legacy_cfg.clone()), Some(legacy_cfg)]);
	let new_channel_manager;
	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	// Initiate channel opening and create the batch channel funding transaction.
	let (tx, funding_created_msgs) = create_batch_channel_funding(&nodes[0], &[
		(&nodes[1], 100_000, 0, 42, None),
		(&nodes[2], 200_000, 0, 43, None),
	]);

	// Go through the funding_created and funding_signed flow with node 1.
	nodes[1].node.handle_funding_created(nodes[0].node.get_our_node_id(), &funding_created_msgs[0]);
	check_added_monitors(&nodes[1], 1);
	expect_channel_pending_event(&nodes[1], &nodes[0].node.get_our_node_id());

	// The monitor is persisted when receiving funding_signed.
	let funding_signed_msg = 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_msg);
	check_added_monitors(&nodes[0], 1);

	// The transaction should not have been broadcast before all channels are ready.
	assert_eq!(nodes[0].tx_broadcaster.txn_broadcast().len(), 0);

	// Reload the node while a subset of the channels in the funding batch have persisted monitors.
	let channel_id_1 = ChannelId::v1_from_funding_outpoint(OutPoint { txid: tx.compute_txid(), index: 0 });
	let node_encoded = nodes[0].node.encode();
	let channel_monitor_1_serialized = get_monitor!(nodes[0], channel_id_1).encode();
	reload_node!(nodes[0], node_encoded, &[&channel_monitor_1_serialized], new_persister, new_chain_monitor, new_channel_manager);

	// Process monitor events.
	assert!(nodes[0].node.get_and_clear_pending_events().is_empty());

	// The monitor should become closed.
	check_added_monitors(&nodes[0], 1);
	{
		let mut monitor_updates = nodes[0].chain_monitor.monitor_updates.lock().unwrap();
		let monitor_updates_1 = monitor_updates.get(&channel_id_1).unwrap();
		assert_eq!(monitor_updates_1.len(), 1);
		assert_eq!(monitor_updates_1[0].updates.len(), 1);
		assert!(matches!(monitor_updates_1[0].updates[0], ChannelMonitorUpdateStep::ChannelForceClosed { .. }));
	}

	// The funding transaction should not have been broadcast, but we broadcast the force-close
	// transaction as part of closing the monitor.
	{
		let broadcasted_txs = nodes[0].tx_broadcaster.txn_broadcast();
		assert_eq!(broadcasted_txs.len(), 1);
		assert!(broadcasted_txs[0].compute_txid() != tx.compute_txid());
		assert_eq!(broadcasted_txs[0].input.len(), 1);
		assert_eq!(broadcasted_txs[0].input[0].previous_output.txid, tx.compute_txid());
	}

	// Ensure the channels don't exist anymore.
	assert!(nodes[0].node.list_channels().is_empty());
}

#[test]
fn test_htlc_localremoved_persistence() {
	// Tests that if we fail an htlc back (update_fail_htlc message) and then restart the node, the node will resend the
	// exact same fail message.
	let chanmon_cfgs: Vec<TestChanMonCfg> = create_chanmon_cfgs(2);
	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);

	let persister;
	let chain_monitor;
	let deserialized_chanmgr;

	// Send a keysend payment that fails because of a preimage mismatch.
	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);

	let payee_pubkey = nodes[1].node.get_our_node_id();

	let _chan = create_chan_between_nodes(&nodes[0], &nodes[1]);
	let route_params = RouteParameters::from_payment_params_and_value(
		PaymentParameters::for_keysend(payee_pubkey, 40, false), 10_000);
	let route = find_route(
		&nodes[0], &route_params
	).unwrap();

	let test_preimage = PaymentPreimage([42; 32]);
	let mismatch_payment_hash = PaymentHash([43; 32]);
	let session_privs = nodes[0].node.test_add_new_pending_payment(mismatch_payment_hash,
		RecipientOnionFields::spontaneous_empty(10_000), PaymentId(mismatch_payment_hash.0), &route).unwrap();
	nodes[0].node.test_send_payment_internal(&route, mismatch_payment_hash,
		RecipientOnionFields::spontaneous_empty(10_000), Some(test_preimage), PaymentId(mismatch_payment_hash.0), session_privs).unwrap();
	check_added_monitors(&nodes[0], 1);

	let updates = get_htlc_update_msgs(&nodes[0], &nodes[1].node.get_our_node_id());
	nodes[1].node.handle_update_add_htlc(nodes[0].node.get_our_node_id(), &updates.update_add_htlcs[0]);
	do_commitment_signed_dance(&nodes[1], &nodes[0], &updates.commitment_signed, false, false);
	expect_and_process_pending_htlcs(&nodes[1], false);
	expect_htlc_handling_failed_destinations!(nodes[1].node.get_and_clear_pending_events(), &[HTLCHandlingFailureType::Receive { payment_hash: mismatch_payment_hash }]);
	check_added_monitors(&nodes[1], 1);

	// Save the update_fail_htlc message for later comparison.
	let msgs = get_htlc_update_msgs(&nodes[1], &nodes[0].node.get_our_node_id());
	let htlc_fail_msg = msgs.update_fail_htlcs[0].clone();

	// Reload nodes.
	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());

	let monitor_encoded = get_monitor!(nodes[1], _chan.3).encode();
	reload_node!(nodes[1], nodes[1].node.encode(), &[&monitor_encoded], persister, chain_monitor, deserialized_chanmgr);

	nodes[0].node.peer_connected(nodes[1].node.get_our_node_id(), &msgs::Init {
		features: nodes[1].node.init_features(), networks: None, remote_network_address: None
	}, true).unwrap();
	let reestablish_1 = get_chan_reestablish_msgs!(nodes[0], nodes[1]);
	assert_eq!(reestablish_1.len(), 1);
	nodes[1].node.peer_connected(nodes[0].node.get_our_node_id(), &msgs::Init {
		features: nodes[0].node.init_features(), networks: None, remote_network_address: None
	}, false).unwrap();
	let reestablish_2 = get_chan_reestablish_msgs!(nodes[1], nodes[0]);
	assert_eq!(reestablish_2.len(), 1);
	nodes[0].node.handle_channel_reestablish(nodes[1].node.get_our_node_id(), &reestablish_2[0]);
	handle_chan_reestablish_msgs!(nodes[0], nodes[1]);
	nodes[1].node.handle_channel_reestablish(nodes[0].node.get_our_node_id(), &reestablish_1[0]);

	// Assert that same failure message is resent after reload.
	let msgs = handle_chan_reestablish_msgs!(nodes[1], nodes[0]);
	let htlc_fail_msg_after_reload = msgs.2.unwrap().update_fail_htlcs[0].clone();
	assert_eq!(htlc_fail_msg, htlc_fail_msg_after_reload);
}



#[test]
#[cfg(peer_storage)]
fn test_peer_storage() {
	let chanmon_cfgs = create_chanmon_cfgs(2);
	let (persister, chain_monitor);
	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
	let nodes_0_deserialized;
	let legacy_cfg = test_legacy_channel_config();
	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[Some(legacy_cfg.clone()), Some(legacy_cfg)]);
	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);

	let node_a_id = nodes[0].node.get_our_node_id();
	let node_b_id = nodes[1].node.get_our_node_id();

	let (_, _, cid, _) = create_announced_chan_between_nodes(&nodes, 0, 1);
	send_payment(&nodes[0], &[&nodes[1]], 1000);
	let nodes_0_serialized = nodes[0].node.encode();
	let old_state_monitor = get_monitor!(nodes[0], cid).encode();
	send_payment(&nodes[0], &[&nodes[1]], 10000);
	send_payment(&nodes[0], &[&nodes[1]], 9999);

	// Update peer storage with latest commitment txns
	connect_blocks(&nodes[0], 1);
	connect_blocks(&nodes[0], 1);

	let peer_storage_msg_events_node0 =
		nodes[0].chain_monitor.chain_monitor.get_and_clear_pending_msg_events();
	let peer_storage_msg_events_node1 =
		nodes[1].chain_monitor.chain_monitor.get_and_clear_pending_msg_events();
	assert_ne!(peer_storage_msg_events_node0.len(), 0);
	assert_ne!(peer_storage_msg_events_node1.len(), 0);

	for ps_msg in peer_storage_msg_events_node0 {
		match ps_msg {
			MessageSendEvent::SendPeerStorage { ref node_id, ref msg } => {
				assert_eq!(*node_id, node_b_id);
				nodes[1].node.handle_peer_storage(node_a_id, msg.clone());
			},
			_ => panic!("Unexpected event"),
		}
	}

	for ps_msg in peer_storage_msg_events_node1 {
		match ps_msg {
			MessageSendEvent::SendPeerStorage { ref node_id, ref msg } => {
				assert_eq!(*node_id, node_a_id);
				nodes[0].node.handle_peer_storage(node_b_id, msg.clone());
			},
			_ => panic!("Unexpected event"),
		}
	}

	nodes[0].node.peer_disconnected(node_b_id);
	nodes[1].node.peer_disconnected(node_a_id);

	// Reload Node!
	// TODO: Handle the case where we've completely forgotten about an active channel.
	reload_node!(
		nodes[0],
		test_legacy_channel_config(),
		&nodes_0_serialized,
		&[&old_state_monitor[..]],
		persister,
		chain_monitor,
		nodes_0_deserialized
	);

	let init_msg = msgs::Init {
		features: nodes[1].node.init_features(),
		networks: None,
		remote_network_address: None,
	};

	nodes[0].node.peer_connected(node_b_id, &init_msg, true).unwrap();
	nodes[1].node.peer_connected(node_a_id, &init_msg, true).unwrap();

	let node_1_events = nodes[1].node.get_and_clear_pending_msg_events();
	assert_eq!(node_1_events.len(), 2);

	let node_0_events = nodes[0].node.get_and_clear_pending_msg_events();
	assert_eq!(node_0_events.len(), 1);

	match node_0_events[0] {
		MessageSendEvent::SendChannelReestablish { ref node_id, .. } => {
			assert_eq!(*node_id, node_b_id);
			// nodes[0] would send a stale channel reestablish, so there's no need to handle this.
		},
		_ => panic!("Unexpected event"),
	}

	if let MessageSendEvent::SendPeerStorageRetrieval { node_id, msg } = &node_1_events[0] {
		assert_eq!(*node_id, node_a_id);
		// Should Panic here!
		let res = std::panic::catch_unwind(|| {
			nodes[0].node.handle_peer_storage_retrieval(node_b_id, msg.clone());
		});
		assert!(res.is_err());
	} else {
		panic!("Unexpected event {node_1_events:?}")
	}

	if let MessageSendEvent::SendChannelReestablish { .. } = &node_1_events[1] {
		// After the `peer_storage_retreival` message would come a `channel_reestablish` (which
		// would also cause nodes[0] to panic) but it already went down due to lost state so
		// there's nothing to deliver.
	} else {
		panic!("Unexpected event {node_1_events:?}")
	}
	// When we panic'd, we expect to panic on `Drop`.
	let res = std::panic::catch_unwind(|| drop(nodes));
	assert!(res.is_err());
}

#[test]
fn test_hold_completed_inflight_monitor_updates_upon_manager_reload() {
	// Test that if a `ChannelMonitorUpdate` completes after the `ChannelManager` is serialized,
	// but before it is deserialized, we hold any completed in-flight updates until background event
	// processing. Previously, we would remove completed monitor updates from
	// `in_flight_monitor_updates` during deserialization, relying on
	// [`ChannelManager::process_background_events`] to eventually be called before the
	// `ChannelManager` is serialized again such that the channel is resumed and further updates can
	// be made.
	let chanmon_cfgs = create_chanmon_cfgs(2);
	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
	let (persister_a, persister_b);
	let (chain_monitor_a, chain_monitor_b);

	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
	let nodes_0_deserialized_a;
	let nodes_0_deserialized_b;

	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
	let chan_id = create_announced_chan_between_nodes(&nodes, 0, 1).2;

	send_payment(&nodes[0], &[&nodes[1]], 1_000_000);

	chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);

	// Send a payment that will be pending due to an async monitor update.
	let (route, payment_hash, _, payment_secret) =
		get_route_and_payment_hash!(nodes[0], nodes[1], 1_000_000);
	let payment_id = PaymentId(payment_hash.0);
	let onion = RecipientOnionFields::secret_only(payment_secret, 1_000_000);
	nodes[0].node.send_payment_with_route(route, payment_hash, onion, payment_id).unwrap();
	check_added_monitors(&nodes[0], 1);

	assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());

	// Serialize the ChannelManager while the monitor update is still in-flight.
	let node_0_serialized = nodes[0].node.encode();

	// Now complete the monitor update by calling force_channel_monitor_updated.
	// This updates the monitor's state, but the ChannelManager still thinks it's pending.
	let (_, latest_update_id) = nodes[0].chain_monitor.get_latest_mon_update_id(chan_id);
	nodes[0].chain_monitor.chain_monitor.force_channel_monitor_updated(chan_id, latest_update_id);
	let monitor_serialized_updated = get_monitor!(nodes[0], chan_id).encode();

	// Reload the node with the updated monitor. Upon deserialization, the ChannelManager will
	// detect that the monitor update completed (monitor's update_id >= the in-flight update_id)
	// and queue a `BackgroundEvent::MonitorUpdatesComplete`.
	nodes[0].node.peer_disconnected(nodes[1].node.get_our_node_id());
	nodes[1].node.peer_disconnected(nodes[0].node.get_our_node_id());
	reload_node!(
		nodes[0],
		test_default_channel_config(),
		&node_0_serialized,
		&[&monitor_serialized_updated[..]],
		persister_a,
		chain_monitor_a,
		nodes_0_deserialized_a
	);

	// If we serialize again, even though we haven't processed any background events yet, we should
	// still see the `BackgroundEvent::MonitorUpdatesComplete` be regenerated on startup.
	let node_0_serialized = nodes[0].node.encode();
	reload_node!(
		nodes[0],
		test_default_channel_config(),
		&node_0_serialized,
		&[&monitor_serialized_updated[..]],
		persister_b,
		chain_monitor_b,
		nodes_0_deserialized_b
	);

	// Reconnect the nodes. We should finally see the `update_add_htlc` go out, as the reconnection
	// should first process `BackgroundEvent::MonitorUpdatesComplete, allowing the channel to be
	// resumed.
	let mut reconnect_args = ReconnectArgs::new(&nodes[0], &nodes[1]);
	reconnect_args.pending_htlc_adds = (0, 1);
	reconnect_nodes(reconnect_args);
}

#[test]
fn outbound_removed_holding_cell_resolved_no_double_forward() {
	// Test that if a forwarding node has an HTLC that is fully removed on the outbound edge
	// but where the inbound edge resolution is in the holding cell, and we reload the node in this
	// state, that node will not double-forward the HTLC.

	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
	let nodes_1_deserialized;
	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	let node_0_id = nodes[0].node.get_our_node_id();
	let node_1_id = nodes[1].node.get_our_node_id();
	let node_2_id = nodes[2].node.get_our_node_id();

	let chan_0_1 = create_announced_chan_between_nodes(&nodes, 0, 1);
	let chan_1_2 = create_announced_chan_between_nodes(&nodes, 1, 2);

	let chan_id_0_1 = chan_0_1.2;
	let chan_id_1_2 = chan_1_2.2;

	// Send a payment from nodes[0] to nodes[2] via nodes[1].
	let (route, payment_hash, payment_preimage, payment_secret) =
		get_route_and_payment_hash!(nodes[0], nodes[2], 1_000_000);
	send_along_route_with_secret(
		&nodes[0], route, &[&[&nodes[1], &nodes[2]]], 1_000_000, payment_hash, payment_secret,
	);

	// Claim the payment on nodes[2].
	nodes[2].node.claim_funds(payment_preimage);
	check_added_monitors(&nodes[2], 1);
	expect_payment_claimed!(nodes[2], payment_hash, 1_000_000);

	// Disconnect nodes[0] from nodes[1] BEFORE processing the fulfill.
	// This forces the inbound fulfill resolution go to into nodes[1]'s holding cell for the inbound
	// channel.
	nodes[0].node.peer_disconnected(node_1_id);
	nodes[1].node.peer_disconnected(node_0_id);

	// Process the fulfill from nodes[2] to nodes[1].
	let updates_2_1 = get_htlc_update_msgs(&nodes[2], &node_1_id);
	nodes[1].node.handle_update_fulfill_htlc(node_2_id, updates_2_1.update_fulfill_htlcs[0].clone());
	check_added_monitors(&nodes[1], 1);
	do_commitment_signed_dance(&nodes[1], &nodes[2], &updates_2_1.commitment_signed, false, false);
	expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], Some(1000), false, false);

	// At this point:
	// - The outbound HTLC nodes[1]->nodes[2] is resolved and removed
	// - The inbound HTLC nodes[0]->nodes[1] is still in a Committed state, with the fulfill
	//   resolution in nodes[1]'s chan_0_1 holding cell
	let node_1_serialized = nodes[1].node.encode();
	let mon_0_1_serialized = get_monitor!(nodes[1], chan_id_0_1).encode();
	let mon_1_2_serialized = get_monitor!(nodes[1], chan_id_1_2).encode();

	// Reload nodes[1].
	// During deserialization, we previously would have not noticed that the nodes[0]<>nodes[1] HTLC
	// had a resolution pending in the holding cell, and reconstructed the ChannelManager's pending
	// HTLC state indicating that the HTLC still needed to be forwarded to the outbound edge.
	reload_node!(
		nodes[1],
		node_1_serialized,
		&[&mon_0_1_serialized, &mon_1_2_serialized],
		persister,
		new_chain_monitor,
		nodes_1_deserialized
	);

	// Check that nodes[1] doesn't double-forward the HTLC.
	nodes[1].node.process_pending_htlc_forwards();

	// Reconnect nodes[1] to nodes[0]. The claim should be in nodes[1]'s holding cell.
	let mut reconnect_args = ReconnectArgs::new(&nodes[1], &nodes[0]);
	reconnect_args.pending_cell_htlc_claims = (0, 1);
	reconnect_nodes(reconnect_args);

	// nodes[0] should now have received the fulfill and generate PaymentSent.
	expect_payment_sent(&nodes[0], payment_preimage, None, true, true);
}

#[test]
fn test_reload_node_with_preimage_in_monitor_claims_htlc() {
	// Test that if a forwarding node has an HTLC that was irrevocably removed on the outbound edge
	// via claim but is still forwarded-and-unresolved in the inbound edge, that HTLC will not be
	// failed back on the inbound edge on reload.
	//
	// For context, the ChannelManager is moving towards reconstructing the pending inbound HTLC set
	// from Channel data on startup. If we find an inbound HTLC that is flagged as already-forwarded,
	// we then check that the HTLC is either (a) still present in the outbound edge or (b) removed
	// from the outbound edge but with a preimage present in the corresponding ChannelMonitor,
	// indicating that it was removed from the outbound edge via claim. If neither of those are the
	// case, we infer that the HTLC was removed from the outbound edge via failure and fail the HTLC
	// backwards.
	//
	// Here we ensure that inbound HTLCs in case (b) above will not be failed backwards on manager
	// reload.

	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
	let nodes_1_deserialized;
	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	let node_0_id = nodes[0].node.get_our_node_id();
	let node_1_id = nodes[1].node.get_our_node_id();
	let node_2_id = nodes[2].node.get_our_node_id();

	let chan_0_1 = create_announced_chan_between_nodes(&nodes, 0, 1);
	let chan_1_2 = create_announced_chan_between_nodes(&nodes, 1, 2);

	let chan_id_0_1 = chan_0_1.2;
	let chan_id_1_2 = chan_1_2.2;

	// Send a payment from nodes[0] to nodes[2] via nodes[1].
	let (route, payment_hash, payment_preimage, payment_secret) =
		get_route_and_payment_hash!(nodes[0], nodes[2], 1_000_000);
	send_along_route_with_secret(
		&nodes[0], route, &[&[&nodes[1], &nodes[2]]], 1_000_000, payment_hash, payment_secret,
	);

	// Claim the payment on nodes[2].
	nodes[2].node.claim_funds(payment_preimage);
	check_added_monitors(&nodes[2], 1);
	expect_payment_claimed!(nodes[2], payment_hash, 1_000_000);

	// Disconnect nodes[0] from nodes[1] BEFORE processing the fulfill.
	// This prevents the claim from propagating back, leaving the inbound HTLC in ::Forwarded state.
	nodes[0].node.peer_disconnected(node_1_id);
	nodes[1].node.peer_disconnected(node_0_id);

	// Process the fulfill from nodes[2] to nodes[1].
	// This stores the preimage in nodes[1]'s monitor for chan_1_2.
	let updates_2_1 = get_htlc_update_msgs(&nodes[2], &node_1_id);
	nodes[1].node.handle_update_fulfill_htlc(node_2_id, updates_2_1.update_fulfill_htlcs[0].clone());
	check_added_monitors(&nodes[1], 1);
	do_commitment_signed_dance(&nodes[1], &nodes[2], &updates_2_1.commitment_signed, false, false);
	expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], Some(1000), false, false);

	// Clear the holding cell's claim entry on chan_0_1 before serialization.
	// This simulates a crash where the HTLC was fully removed from the outbound edge but is still
	// present on the inbound edge without a resolution.
	nodes[1].node.test_clear_channel_holding_cell(node_0_id, chan_id_0_1);

	// At this point:
	// - The inbound HTLC on nodes[1] (from nodes[0]) is in ::Forwarded state
	// - The preimage IS in nodes[1]'s monitor for chan_1_2
	// - The outbound HTLC to nodes[2] is resolved
	//
	// Serialize nodes[1] state and monitors before reloading.
	let node_1_serialized = nodes[1].node.encode();
	let mon_0_1_serialized = get_monitor!(nodes[1], chan_id_0_1).encode();
	let mon_1_2_serialized = get_monitor!(nodes[1], chan_id_1_2).encode();

	// Reload nodes[1].
	// During deserialization, we track inbound HTLCs that purport to already be forwarded on the
	// outbound edge. If any are entirely missing from the outbound edge with no preimage available,
	// they will be failed backwards. Otherwise, as in this case where a preimage is available, the
	// payment should be claimed backwards.
	reload_node!(
		nodes[1],
		node_1_serialized,
		&[&mon_0_1_serialized, &mon_1_2_serialized],
		persister,
		new_chain_monitor,
		nodes_1_deserialized,
		Some(true)
	);

	// When the claim is reconstructed during reload, a PaymentForwarded event is generated.
	// Fetching events triggers the pending monitor update (adding preimage) to be applied.
	expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], Some(1000), false, false);
	check_added_monitors(&nodes[1], 1);

	// Reconnect nodes[1] to nodes[0]. The claim should be in nodes[1]'s holding cell.
	let mut reconnect_args = ReconnectArgs::new(&nodes[1], &nodes[0]);
	reconnect_args.pending_cell_htlc_claims = (0, 1);
	reconnect_nodes(reconnect_args);

	// nodes[0] should now have received the fulfill and generate PaymentSent.
	expect_payment_sent(&nodes[0], payment_preimage, None, true, true);
}

#[test]
fn test_reload_node_without_preimage_fails_htlc() {
	// Test that if a forwarding node has an HTLC that was removed on the outbound edge via failure
	// but is still forwarded-and-unresolved in the inbound edge, that HTLC will be correctly
	// failed back on reload via the already_forwarded_htlcs mechanism.
	//
	// For context, the ChannelManager reconstructs the pending inbound HTLC set from Channel data
	// on startup. If an inbound HTLC is present but flagged as already-forwarded, we check that
	// the HTLC is either (a) still present in the outbound edge or (b) removed from the outbound
	// edge but with a preimage present in the corresponding ChannelMonitor, indicating it was
	// removed via claim. If neither, we infer the HTLC was removed via failure and fail it back.
	//
	// Here we test the failure case: no preimage is present, so the HTLC should be failed back.
	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
	let nodes_1_deserialized;
	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	let node_0_id = nodes[0].node.get_our_node_id();
	let node_1_id = nodes[1].node.get_our_node_id();
	let node_2_id = nodes[2].node.get_our_node_id();

	let chan_0_1 = create_announced_chan_between_nodes(&nodes, 0, 1);
	let chan_1_2 = create_announced_chan_between_nodes(&nodes, 1, 2);

	let chan_id_0_1 = chan_0_1.2;
	let chan_id_1_2 = chan_1_2.2;

	// Send a payment from nodes[0] to nodes[2] via nodes[1].
	let (route, payment_hash, _, payment_secret) =
		get_route_and_payment_hash!(nodes[0], nodes[2], 1_000_000);
	send_along_route_with_secret(
		&nodes[0], route, &[&[&nodes[1], &nodes[2]]], 1_000_000, payment_hash, payment_secret,
	);

	// Disconnect nodes[0] from nodes[1] BEFORE processing the failure.
	// This prevents the fail from propagating back, leaving the inbound HTLC in ::Forwarded state.
	nodes[0].node.peer_disconnected(node_1_id);
	nodes[1].node.peer_disconnected(node_0_id);

	// Fail the payment on nodes[2] and process the failure to nodes[1].
	// This removes the outbound HTLC and queues a fail in the holding cell.
	nodes[2].node.fail_htlc_backwards(&payment_hash);
	expect_and_process_pending_htlcs_and_htlc_handling_failed(
		&nodes[2], &[HTLCHandlingFailureType::Receive { payment_hash }]
	);
	check_added_monitors(&nodes[2], 1);

	let updates_2_1 = get_htlc_update_msgs(&nodes[2], &node_1_id);
	nodes[1].node.handle_update_fail_htlc(node_2_id, &updates_2_1.update_fail_htlcs[0]);
	do_commitment_signed_dance(&nodes[1], &nodes[2], &updates_2_1.commitment_signed, false, false);
	expect_and_process_pending_htlcs_and_htlc_handling_failed(
		&nodes[1], &[HTLCHandlingFailureType::Forward { node_id: Some(node_2_id), channel_id: chan_id_1_2 }]
	);

	// Clear the holding cell's fail entry on chan_0_1 before serialization.
	// This simulates a crash where the HTLC was fully removed from the outbound edge but is still
	// present on the inbound edge without a resolution. Otherwise, we would not be able to exercise
	// the desired failure paths due to the holding cell failure resolution being present.
	nodes[1].node.test_clear_channel_holding_cell(node_0_id, chan_id_0_1);

	// Now serialize. The state has:
	// - Inbound HTLC on chan_0_1 in ::Forwarded state
	// - Outbound HTLC on chan_1_2 resolved (not present)
	// - No preimage in monitors (it was a failure)
	// - No holding cell entry for the fail (we cleared it)
	let node_1_serialized = nodes[1].node.encode();
	let mon_0_1_serialized = get_monitor!(nodes[1], chan_id_0_1).encode();
	let mon_1_2_serialized = get_monitor!(nodes[1], chan_id_1_2).encode();

	// Reload nodes[1].
	// The already_forwarded_htlcs mechanism should detect:
	// - Inbound HTLC is in ::Forwarded state
	// - Outbound HTLC is not present in outbound channel
	// - No preimage in monitors
	// Therefore it should fail the HTLC backwards.
	reload_node!(
		nodes[1],
		node_1_serialized,
		&[&mon_0_1_serialized, &mon_1_2_serialized],
		persister,
		new_chain_monitor,
		nodes_1_deserialized,
		Some(true)
	);

	// After reload, nodes[1] should have generated an HTLCHandlingFailed event.
	let events = nodes[1].node.get_and_clear_pending_events();
	assert!(!events.is_empty(), "Expected HTLCHandlingFailed event");
	for event in events {
		match event {
			Event::HTLCHandlingFailed { .. } => {},
			_ => panic!("Unexpected event {:?}", event),
		}
	}

	// Process the failure so it goes back into chan_0_1's holding cell.
	nodes[1].node.process_pending_htlc_forwards();
	check_added_monitors(&nodes[1], 0); // No monitor update yet (peer disconnected)

	// Reconnect nodes[1] to nodes[0]. The fail should be in nodes[1]'s holding cell.
	let mut reconnect_args = ReconnectArgs::new(&nodes[1], &nodes[0]);
	reconnect_args.pending_cell_htlc_fails = (0, 1);
	reconnect_nodes(reconnect_args);

	// nodes[0] should now have received the failure and generate PaymentFailed.
	expect_payment_failed_conditions(&nodes[0], payment_hash, false, PaymentFailedConditions::new());
}

#[test]
fn test_reload_with_mpp_claims_on_same_channel() {
	// Test that if a forwarding node has two HTLCs for the same MPP payment that were both
	// irrevocably removed on the outbound edge via claim but are still forwarded-and-unresolved
	// on the inbound edge, both HTLCs will be claimed backwards on restart.
	//
	// Topology:
	//   nodes[0] ----chan_0_1----> nodes[1] ----chan_1_2_a----> nodes[2]
	//                                      \----chan_1_2_b---/
	let chanmon_cfgs = create_chanmon_cfgs(3);
	let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
	let persister;
	let new_chain_monitor;
	let mut config = test_default_channel_config();
	// Set the percentage to the default value at the time this test was written
	config.channel_handshake_config.announced_channel_max_inbound_htlc_value_in_flight_percentage = 10;
	let configs: [Option<UserConfig>; 3] = core::array::from_fn(|_| Some(config.clone()));
	let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &configs);
	let nodes_1_deserialized;
	let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);

	let node_0_id = nodes[0].node.get_our_node_id();
	let node_1_id = nodes[1].node.get_our_node_id();
	let node_2_id = nodes[2].node.get_our_node_id();

	let chan_0_1 = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 2_000_000, 0);
	let chan_1_2_a = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 1_000_000, 0);
	let chan_1_2_b = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 1_000_000, 0);

	let chan_id_0_1 = chan_0_1.2;
	let chan_id_1_2_a = chan_1_2_a.2;
	let chan_id_1_2_b = chan_1_2_b.2;

	// Send an MPP payment large enough that the router must split it across both outbound channels.
	// Each 1M sat outbound channel has 100M msat max in-flight, so 150M msat requires splitting.
	let amt_msat = 150_000_000;
	let (route, payment_hash, payment_preimage, payment_secret) =
		get_route_and_payment_hash!(nodes[0], nodes[2], amt_msat);

	let payment_id = PaymentId(nodes[0].keys_manager.backing.get_secure_random_bytes());
	let onion = RecipientOnionFields::secret_only(payment_secret, amt_msat);
	nodes[0].node.send_payment_with_route(route, payment_hash, onion, payment_id).unwrap();
	check_added_monitors(&nodes[0], 1);

	// Forward the first HTLC nodes[0] -> nodes[1] -> nodes[2]. Note that the second HTLC is released
	// from the holding cell during the first HTLC's commitment_signed_dance.
	let mut events = nodes[0].node.get_and_clear_pending_msg_events();
	assert_eq!(events.len(), 1);
	let payment_event_1 = SendEvent::from_event(events.remove(0));

	nodes[1].node.handle_update_add_htlc(node_0_id, &payment_event_1.msgs[0]);
	check_added_monitors(&nodes[1], 0);
	nodes[1].node.handle_commitment_signed_batch_test(node_0_id, &payment_event_1.commitment_msg);
	check_added_monitors(&nodes[1], 1);
	let (_, raa, holding_cell_htlcs) =
		do_main_commitment_signed_dance(&nodes[1], &nodes[0], false);
	assert_eq!(holding_cell_htlcs.len(), 1);
	let payment_event_2 = holding_cell_htlcs.into_iter().next().unwrap();
	nodes[1].node.handle_revoke_and_ack(node_0_id, &raa);
	check_added_monitors(&nodes[1], 1);

	nodes[1].node.process_pending_htlc_forwards();
	check_added_monitors(&nodes[1], 1);
	let mut events = nodes[1].node.get_and_clear_pending_msg_events();
	assert_eq!(events.len(), 1);
	let ev_1_2 = events.remove(0);
	pass_along_path(
		&nodes[1], &[&nodes[2]], amt_msat, payment_hash, Some(payment_secret), ev_1_2, false, None,
	);

	// Second HTLC: full path nodes[0] -> nodes[1] -> nodes[2]. PaymentClaimable expected at end.
	pass_along_path(
		&nodes[0], &[&nodes[1], &nodes[2]], amt_msat, payment_hash, Some(payment_secret),
		payment_event_2, true, None,
	);

	// Claim the HTLCs such that they're fully removed from the outbound edge, but disconnect
	// node_0<>node_1 so that they can't be claimed backwards by node_1.
	nodes[2].node.claim_funds(payment_preimage);
	check_added_monitors(&nodes[2], 2);
	expect_payment_claimed!(nodes[2], payment_hash, amt_msat);

	nodes[0].node.peer_disconnected(node_1_id);
	nodes[1].node.peer_disconnected(node_0_id);

	let mut events = nodes[2].node.get_and_clear_pending_msg_events();
	assert_eq!(events.len(), 2);
	for ev in events {
		match ev {
			MessageSendEvent::UpdateHTLCs { ref node_id, ref updates, .. } => {
				assert_eq!(*node_id, node_1_id);
				assert_eq!(updates.update_fulfill_htlcs.len(), 1);
				nodes[1].node.handle_update_fulfill_htlc(node_2_id, updates.update_fulfill_htlcs[0].clone());
				check_added_monitors(&nodes[1], 1);
				do_commitment_signed_dance(&nodes[1], &nodes[2], &updates.commitment_signed, false, false);
			},
			_ => panic!("Unexpected event"),
		}
	}

	let events = nodes[1].node.get_and_clear_pending_events();
	assert_eq!(events.len(), 2);
	for event in events {
		expect_payment_forwarded(
			event, &nodes[1], &nodes[0], &nodes[2], Some(1000), None, false, false, false,
		);
	}

	// Clear the holding cell's claim entries on chan_0_1 before serialization.
	// This simulates a crash where both HTLCs were fully removed on the outbound edges but are
	// still present on the inbound edge without a resolution.
	nodes[1].node.test_clear_channel_holding_cell(node_0_id, chan_id_0_1);

	let node_1_serialized = nodes[1].node.encode();
	let mon_0_1_serialized = get_monitor!(nodes[1], chan_id_0_1).encode();
	let mon_1_2_a_serialized = get_monitor!(nodes[1], chan_id_1_2_a).encode();
	let mon_1_2_b_serialized = get_monitor!(nodes[1], chan_id_1_2_b).encode();

	reload_node!(
		nodes[1],
		node_1_serialized,
		&[&mon_0_1_serialized, &mon_1_2_a_serialized, &mon_1_2_b_serialized],
		persister,
		new_chain_monitor,
		nodes_1_deserialized,
		Some(true)
	);
	nodes[1].disable_monitor_completeness_assertion();

	// When the claims are reconstructed during reload, PaymentForwarded events are regenerated.
	let events = nodes[1].node.get_and_clear_pending_events();
	assert_eq!(events.len(), 2);
	for event in events {
		expect_payment_forwarded(
			event, &nodes[1], &nodes[0], &nodes[2], Some(1000), None, false, false, false,
		);
	}
	// Fetching events triggers the pending monitor updates (one for each HTLC preimage) to be applied.
	check_added_monitors(&nodes[1], 2);

	// Reconnect nodes[1] to nodes[0]. Both claims should be in nodes[1]'s holding cell.
	let mut reconnect_args = ReconnectArgs::new(&nodes[1], &nodes[0]);
	reconnect_args.pending_cell_htlc_claims = (0, 2);
	reconnect_nodes(reconnect_args);

	// nodes[0] should now have received both fulfills and generate PaymentSent.
	expect_payment_sent(&nodes[0], payment_preimage, None, true, true);
}