Prune lockedtime packages when inputs are spent

We have to prune lockedtime packages when their inputs are spent,
otherwise the notification of the watched outputs might be missed. This
can lead to lockedtime packages with spent inputs being added back to
the pending claim requests in the future, and never being cleaned up.

Resolves: #3859

Author: whfuyn

lightning/src/chain/onchaintx.rs

@@ -994,6 +994,17 @@ impl<ChannelSigner: EcdsaChannelSigner> OnchainTxHandler<ChannelSigner> {
 						panic!("Inconsistencies between pending_claim_requests map and claimable_outpoints map");
 					}
 				}
+
+				// Also remove/split any locktimed packages whose inputs have been spent by this transaction.
+				self.locktimed_packages.retain(|_, packages|{
+					packages.retain_mut(|package| {
+						if let Some(p) = package.split_package(&inp.previous_output) {
+							claimed_outputs_material.push(p);
+						}
+						!package.outpoints().is_empty()
+					});
+					!packages.is_empty()
+				});
 			}
 			for package in claimed_outputs_material.drain(..) {
 				let entry = OnchainEventEntry {
@@ -1135,6 +1146,12 @@ impl<ChannelSigner: EcdsaChannelSigner> OnchainTxHandler<ChannelSigner> {
 				//- resurect outpoint back in its claimable set and regenerate tx
 				match entry.event {
 					OnchainEvent::ContentiousOutpoint { package } => {
+						let package_locktime = package.package_locktime(height);
+						if package_locktime > height {
+							self.locktimed_packages.entry(package_locktime).or_default().push(package);
+							continue;
+						}
+
 						if let Some(pending_claim) = self.claimable_outpoints.get(package.outpoints()[0]) {
 							if let Some(request) = self.pending_claim_requests.get_mut(&pending_claim.0) {
 								assert!(request.merge_package(package, height).is_ok());