Remove unnecessary clones of the HTLC-HTLCSource table

Author: tankyleo

lightning/src/ln/channel.rs

@@ -3606,7 +3606,6 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider {
 			}
 			bitcoin_tx.txid
 		};
-		let mut htlcs_cloned: Vec<_> = commitment_data.htlcs_included.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect();
 
 		// If our counterparty updated the channel fee in this commitment transaction, check that
 		// they can actually afford the new fee now.
@@ -3644,8 +3643,8 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider {
 
 		let holder_keys = commitment_data.tx.trust().keys();
 		let mut nondust_htlc_sources = Vec::with_capacity(commitment_data.tx.nondust_htlcs().len());
-		let mut dust_htlcs = Vec::with_capacity(htlcs_cloned.len() - commitment_data.tx.nondust_htlcs().len());
-		for (idx, (htlc, mut source_opt)) in htlcs_cloned.drain(..).enumerate() {
+		let mut dust_htlcs = Vec::with_capacity(commitment_data.htlcs_included.len() - commitment_data.tx.nondust_htlcs().len());
+		for (idx, (htlc, mut source_opt)) in commitment_data.htlcs_included.into_iter().enumerate() {
 			if let Some(_) = htlc.transaction_output_index {
 				let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, commitment_data.tx.feerate_per_kw(),
 					funding.get_counterparty_selected_contest_delay().unwrap(), &htlc, &self.channel_type,
@@ -3662,13 +3661,13 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider {
 				}
 				if htlc.offered {
 					if let Some(source) = source_opt.take() {
-						nondust_htlc_sources.push(source);
+						nondust_htlc_sources.push(source.clone());
 					} else {
 						panic!("Missing outbound HTLC source");
 					}
 				}
 			} else {
-				dust_htlcs.push((htlc, None, source_opt.take()));
+				dust_htlcs.push((htlc, None, source_opt.take().cloned()));
 			}
 			debug_assert!(source_opt.is_none(), "HTLCSource should have been put somewhere");
 		}
@@ -8779,11 +8778,11 @@ impl<SP: Deref> FundedChannel<SP> where
 		}
 		self.context.resend_order = RAACommitmentOrder::RevokeAndACKFirst;
 
-		let (mut htlcs_ref, counterparty_commitment_tx) =
+		let (htlcs_ref, counterparty_commitment_tx) =
 			self.build_commitment_no_state_update(logger);
 		let counterparty_commitment_txid = counterparty_commitment_tx.trust().txid();
-		let htlcs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
-			htlcs_ref.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
+		let htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
+			htlcs_ref.into_iter().map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
 
 		if self.context.announcement_sigs_state == AnnouncementSigsState::MessageSent {
 			self.context.announcement_sigs_state = AnnouncementSigsState::Committed;
@@ -8796,7 +8795,7 @@ impl<SP: Deref> FundedChannel<SP> where
 			// and provide the full commit tx instead of the information needed to rebuild it.
 			updates: vec![ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
 				commitment_txid: counterparty_commitment_txid,
-				htlc_outputs: htlcs.clone(),
+				htlc_outputs,
 				commitment_number: self.context.cur_counterparty_commitment_transaction_number,
 				their_per_commitment_point: self.context.counterparty_cur_commitment_point.unwrap(),
 				feerate_per_kw: Some(counterparty_commitment_tx.feerate_per_kw()),