Test propose channel splice while disconnected

diff --git a/lightning/src/ln/functional_test_utils.rs b/lightning/src/ln/functional_test_utils.rs
index 3d7d69c..d8e59dd 100644
--- a/lightning/src/ln/functional_test_utils.rs
+++ b/lightning/src/ln/functional_test_utils.rs
@@ -1572,6 +1572,14 @@ pub fn sign_funding_transaction<'a, 'b, 'c>(
 pub fn open_zero_conf_channel<'a, 'b, 'c, 'd>(
 	initiator: &'a Node<'b, 'c, 'd>, receiver: &'a Node<'b, 'c, 'd>,
 	initiator_config: Option<UserConfig>,
+) -> (bitcoin::Transaction, ChannelId) {
+	open_zero_conf_channel_with_value(initiator, receiver, initiator_config, 100_000, 10_001)
+}
+
+// Receiver must have been initialized with manually_accept_inbound_channels set to true.
+pub fn open_zero_conf_channel_with_value<'a, 'b, 'c, 'd>(
+	initiator: &'a Node<'b, 'c, 'd>, receiver: &'a Node<'b, 'c, 'd>,
+	initiator_config: Option<UserConfig>, channel_value_sat: u64, push_msat: u64,
 ) -> (bitcoin::Transaction, ChannelId) {
 	let initiator_channels = initiator.node.list_usable_channels().len();
 	let receiver_channels = receiver.node.list_usable_channels().len();
@@ -1581,7 +1589,7 @@ pub fn open_zero_conf_channel<'a, 'b, 'c, 'd>(
 
 	initiator
 		.node
-		.create_channel(receiver_node_id, 100_000, 10_001, 42, None, initiator_config)
+		.create_channel(receiver_node_id, channel_value_sat, push_msat, 42, None, initiator_config)
 		.unwrap();
 	let open_channel =
 		get_event_msg!(initiator, MessageSendEvent::SendOpenChannel, receiver_node_id);
@@ -1610,7 +1618,7 @@ pub fn open_zero_conf_channel<'a, 'b, 'c, 'd>(
 	initiator.node.handle_accept_channel(receiver_node_id, &accept_channel);
 
 	let (temporary_channel_id, tx, _) =
-		create_funding_transaction(&initiator, &receiver_node_id, 100_000, 42);
+		create_funding_transaction(&initiator, &receiver_node_id, channel_value_sat, 42);
 	initiator
 		.node
 		.funding_transaction_generated(temporary_channel_id, receiver_node_id, tx.clone())
diff --git a/lightning/src/ln/splicing_tests.rs b/lightning/src/ln/splicing_tests.rs
index deb76a7..db34969 100644
--- a/lightning/src/ln/splicing_tests.rs
+++ b/lightning/src/ln/splicing_tests.rs
@@ -1178,6 +1178,319 @@ fn do_test_splice_reestablish(reload: bool, async_monitor_update: bool) {
 		.remove_watched_txn_and_outputs(prev_funding_outpoint, prev_funding_script);
 }
 
+#[test]
+fn test_propose_splice_while_disconnected() {
+	do_test_propose_splice_while_disconnected(false, false);
+	do_test_propose_splice_while_disconnected(false, true);
+	do_test_propose_splice_while_disconnected(true, false);
+	do_test_propose_splice_while_disconnected(true, true);
+}
+
+fn do_test_propose_splice_while_disconnected(reload: bool, use_0conf: bool) {
+	// Test that both nodes are able to propose a splice while the counterparty is disconnected, and
+	// whoever doesn't go first due to the quiescence tie-breaker, will retry their splice after the
+	// first one becomes locked.
+	let chanmon_cfgs = create_chanmon_cfgs(2);
+	let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
+	let (persister_0a, persister_0b, persister_1a, persister_1b);
+	let (chain_monitor_0a, chain_monitor_0b, chain_monitor_1a, chain_monitor_1b);
+	let mut config = test_default_channel_config();
+	if use_0conf {
+		config.manually_accept_inbound_channels = true;
+		config.channel_handshake_limits.trust_own_funding_0conf = true;
+	}
+	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[Some(config.clone()), Some(config)]);
+	let (node_0a, node_0b, node_1a, node_1b);
+	let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
+
+	let node_id_0 = nodes[0].node.get_our_node_id();
+	let node_id_1 = nodes[1].node.get_our_node_id();
+
+	let initial_channel_value_sat = 1_000_000;
+	let push_msat = initial_channel_value_sat / 2 * 1000;
+	let channel_id = if use_0conf {
+		let (funding_tx, channel_id) = open_zero_conf_channel_with_value(
+			&nodes[0],
+			&nodes[1],
+			None,
+			initial_channel_value_sat,
+			push_msat,
+		);
+		mine_transaction(&nodes[0], &funding_tx);
+		mine_transaction(&nodes[1], &funding_tx);
+		channel_id
+	} else {
+		let (_, _, channel_id, _) = create_announced_chan_between_nodes_with_value(
+			&nodes,
+			0,
+			1,
+			initial_channel_value_sat,
+			push_msat,
+		);
+		channel_id
+	};
+
+	// Start with the nodes disconnected, and have each one attempt a splice.
+	nodes[0].node.peer_disconnected(node_id_1);
+	nodes[1].node.peer_disconnected(node_id_0);
+
+	let splice_out_sat = initial_channel_value_sat / 4;
+	let node_0_contribution = SpliceContribution::SpliceOut {
+		outputs: vec![TxOut {
+			value: Amount::from_sat(splice_out_sat),
+			script_pubkey: nodes[0].wallet_source.get_change_script().unwrap(),
+		}],
+	};
+	nodes[0]
+		.node
+		.splice_channel(
+			&channel_id,
+			&node_id_1,
+			node_0_contribution.clone(),
+			FEERATE_FLOOR_SATS_PER_KW,
+			None,
+		)
+		.unwrap();
+	assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+
+	let node_1_contribution = SpliceContribution::SpliceOut {
+		outputs: vec![TxOut {
+			value: Amount::from_sat(splice_out_sat),
+			script_pubkey: nodes[1].wallet_source.get_change_script().unwrap(),
+		}],
+	};
+	nodes[1]
+		.node
+		.splice_channel(
+			&channel_id,
+			&node_id_0,
+			node_1_contribution.clone(),
+			FEERATE_FLOOR_SATS_PER_KW,
+			None,
+		)
+		.unwrap();
+	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+
+	if reload {
+		let encoded_monitor_0 = get_monitor!(nodes[0], channel_id).encode();
+		reload_node!(
+			nodes[0],
+			nodes[0].node.encode(),
+			&[&encoded_monitor_0],
+			persister_0a,
+			chain_monitor_0a,
+			node_0a
+		);
+		let encoded_monitor_1 = get_monitor!(nodes[1], channel_id).encode();
+		reload_node!(
+			nodes[1],
+			nodes[1].node.encode(),
+			&[&encoded_monitor_1],
+			persister_1a,
+			chain_monitor_1a,
+			node_1a
+		);
+	}
+
+	// Reconnect the nodes. Both nodes should attempt quiescence as the initiator, but only one will
+	// be it via the tie-breaker.
+	let mut reconnect_args = ReconnectArgs::new(&nodes[0], &nodes[1]);
+	reconnect_args.send_channel_ready = (true, true);
+	if !use_0conf {
+		reconnect_args.send_announcement_sigs = (true, true);
+	}
+	reconnect_args.send_stfu = (true, true);
+	reconnect_nodes(reconnect_args);
+	let splice_init = get_event_msg!(nodes[0], MessageSendEvent::SendSpliceInit, node_id_1);
+	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+
+	let (prev_funding_outpoint, prev_funding_script) = nodes[0]
+		.chain_monitor
+		.chain_monitor
+		.get_monitor(channel_id)
+		.map(|monitor| (monitor.get_funding_txo(), monitor.get_funding_script()))
+		.unwrap();
+
+	// Negotiate the first splice to completion.
+	let initial_commit_sig = {
+		nodes[1].node.handle_splice_init(node_id_0, &splice_init);
+		let splice_ack = get_event_msg!(nodes[1], MessageSendEvent::SendSpliceAck, node_id_0);
+		nodes[0].node.handle_splice_ack(node_id_1, &splice_ack);
+		let new_funding_script = chan_utils::make_funding_redeemscript(
+			&splice_init.funding_pubkey,
+			&splice_ack.funding_pubkey,
+		)
+		.to_p2wsh();
+		complete_interactive_funding_negotiation(
+			&nodes[0],
+			&nodes[1],
+			channel_id,
+			node_0_contribution,
+			new_funding_script,
+		)
+	};
+	let (splice_tx, splice_locked) =
+		sign_interactive_funding_tx(&nodes[0], &nodes[1], initial_commit_sig, use_0conf);
+	expect_splice_pending_event(&nodes[0], &node_id_1);
+	expect_splice_pending_event(&nodes[1], &node_id_0);
+
+	let splice_locked = if use_0conf {
+		let (splice_locked, for_node_id) = splice_locked.unwrap();
+		assert_eq!(for_node_id, node_id_1);
+		splice_locked
+	} else {
+		assert!(splice_locked.is_none());
+
+		mine_transaction(&nodes[0], &splice_tx);
+		mine_transaction(&nodes[1], &splice_tx);
+
+		// Mine enough blocks for the first splice to become locked.
+		connect_blocks(&nodes[0], ANTI_REORG_DELAY - 1);
+		connect_blocks(&nodes[1], ANTI_REORG_DELAY - 1);
+
+		get_event_msg!(nodes[0], MessageSendEvent::SendSpliceLocked, node_id_1)
+	};
+	nodes[1].node.handle_splice_locked(node_id_0, &splice_locked);
+
+	// We should see the node which lost the tie-breaker attempt their splice now by first
+	// negotiating quiescence, but their `stfu` won't be sent until after another reconnection.
+	let msg_events = nodes[1].node.get_and_clear_pending_msg_events();
+	assert_eq!(msg_events.len(), if use_0conf { 2 } else { 3 }, "{msg_events:?}");
+	if let MessageSendEvent::SendSpliceLocked { ref msg, .. } = &msg_events[0] {
+		nodes[0].node.handle_splice_locked(node_id_1, msg);
+		if use_0conf {
+			// TODO(splicing): Revisit splice transaction rebroadcasts.
+			let txn_0 = nodes[0].tx_broadcaster.txn_broadcast();
+			assert_eq!(txn_0.len(), 1);
+			assert_eq!(&txn_0[0], &splice_tx);
+			mine_transaction(&nodes[0], &splice_tx);
+			mine_transaction(&nodes[1], &splice_tx);
+		}
+	} else {
+		panic!("Unexpected event {:?}", &msg_events[0]);
+	}
+	if !use_0conf {
+		if let MessageSendEvent::SendAnnouncementSignatures { ref msg, .. } = &msg_events[1] {
+			nodes[0].node.handle_announcement_signatures(node_id_1, msg);
+		} else {
+			panic!("Unexpected event {:?}", &msg_events[1]);
+		}
+	}
+	assert!(matches!(
+		&msg_events[if use_0conf { 1 } else { 2 }],
+		MessageSendEvent::SendStfu { .. }
+	));
+
+	let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+	assert_eq!(msg_events.len(), if use_0conf { 0 } else { 2 }, "{msg_events:?}");
+	if !use_0conf {
+		if let MessageSendEvent::SendAnnouncementSignatures { ref msg, .. } = &msg_events[0] {
+			nodes[1].node.handle_announcement_signatures(node_id_0, msg);
+		} else {
+			panic!("Unexpected event {:?}", &msg_events[1]);
+		}
+		assert!(matches!(&msg_events[1], MessageSendEvent::BroadcastChannelAnnouncement { .. }));
+	}
+
+	let msg_events = nodes[1].node.get_and_clear_pending_msg_events();
+	assert_eq!(msg_events.len(), if use_0conf { 0 } else { 1 }, "{msg_events:?}");
+	if !use_0conf {
+		assert!(matches!(&msg_events[0], MessageSendEvent::BroadcastChannelAnnouncement { .. }));
+	}
+
+	expect_channel_ready_event(&nodes[0], &node_id_1);
+	check_added_monitors(&nodes[0], 1);
+	expect_channel_ready_event(&nodes[1], &node_id_0);
+	check_added_monitors(&nodes[1], 1);
+
+	// Remove the corresponding outputs and transactions the chain source is watching for the
+	// old funding as it is no longer being tracked.
+	nodes[0]
+		.chain_source
+		.remove_watched_txn_and_outputs(prev_funding_outpoint, prev_funding_script.clone());
+	nodes[1]
+		.chain_source
+		.remove_watched_txn_and_outputs(prev_funding_outpoint, prev_funding_script);
+
+	// Reconnect the nodes. This should trigger the node which lost the tie-breaker to resend `stfu`
+	// for their splice attempt.
+	if reload {
+		let encoded_monitor_0 = get_monitor!(nodes[0], channel_id).encode();
+		reload_node!(
+			nodes[0],
+			nodes[0].node.encode(),
+			&[&encoded_monitor_0],
+			persister_0b,
+			chain_monitor_0b,
+			node_0b
+		);
+		let encoded_monitor_1 = get_monitor!(nodes[1], channel_id).encode();
+		reload_node!(
+			nodes[1],
+			nodes[1].node.encode(),
+			&[&encoded_monitor_1],
+			persister_1b,
+			chain_monitor_1b,
+			node_1b
+		);
+	} else {
+		nodes[0].node.peer_disconnected(node_id_1);
+		nodes[1].node.peer_disconnected(node_id_0);
+	}
+	let mut reconnect_args = ReconnectArgs::new(&nodes[0], &nodes[1]);
+	if !use_0conf {
+		reconnect_args.send_announcement_sigs = (true, true);
+	}
+	reconnect_args.send_stfu = (true, false);
+	reconnect_nodes(reconnect_args);
+
+	// Drive the second splice to completion.
+	let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+	assert_eq!(msg_events.len(), 1, "{msg_events:?}");
+	if let MessageSendEvent::SendStfu { ref msg, .. } = msg_events[0] {
+		nodes[1].node.handle_stfu(node_id_0, msg);
+	} else {
+		panic!("Unexpected event {:?}", &msg_events[0]);
+	}
+
+	let splice_init = get_event_msg!(nodes[1], MessageSendEvent::SendSpliceInit, node_id_0);
+	let initial_commit_sig = {
+		nodes[0].node.handle_splice_init(node_id_1, &splice_init);
+		let splice_ack = get_event_msg!(nodes[0], MessageSendEvent::SendSpliceAck, node_id_1);
+		nodes[1].node.handle_splice_ack(node_id_0, &splice_ack);
+		let new_funding_script = chan_utils::make_funding_redeemscript(
+			&splice_init.funding_pubkey,
+			&splice_ack.funding_pubkey,
+		)
+		.to_p2wsh();
+		complete_interactive_funding_negotiation(
+			&nodes[1],
+			&nodes[0],
+			channel_id,
+			node_1_contribution,
+			new_funding_script,
+		)
+	};
+	let (splice_tx, splice_locked) =
+		sign_interactive_funding_tx(&nodes[1], &nodes[0], initial_commit_sig, use_0conf);
+	expect_splice_pending_event(&nodes[0], &node_id_1);
+	expect_splice_pending_event(&nodes[1], &node_id_0);
+
+	if use_0conf {
+		let (splice_locked, for_node_id) = splice_locked.unwrap();
+		assert_eq!(for_node_id, node_id_0);
+		lock_splice(&nodes[1], &nodes[0], &splice_locked, true);
+	} else {
+		assert!(splice_locked.is_none());
+		mine_transaction(&nodes[0], &splice_tx);
+		mine_transaction(&nodes[1], &splice_tx);
+		lock_splice_after_blocks(&nodes[1], &nodes[0], ANTI_REORG_DELAY - 1);
+	}
+
+	// Sanity check that we can still make a test payment.
+	send_payment(&nodes[0], &[&nodes[1]], 1_000_000);
+}
+
 #[test]
 fn disconnect_on_unexpected_interactive_tx_message() {
 	let chanmon_cfgs = create_chanmon_cfgs(2);