Merge pull request #2403 from wpaulino/bump-transaction-event-handler-tests

Integrate BumpTransactionEventHandler into existing anchor tests

Author: TheBlueMatt

lightning/src/chain/chaininterface.rs

@@ -14,9 +14,18 @@
 //! disconnections, transaction broadcasting, and feerate information requests.
 
 use core::{cmp, ops::Deref};
+use core::convert::TryInto;
 
 use bitcoin::blockdata::transaction::Transaction;
 
+// TODO: Define typed abstraction over feerates to handle their conversions.
+pub(crate) fn compute_feerate_sat_per_1000_weight(fee_sat: u64, weight: u64) -> u32 {
+	(fee_sat * 1000 / weight).try_into().unwrap_or(u32::max_value())
+}
+pub(crate) const fn fee_for_weight(feerate_sat_per_1000_weight: u32, weight: u64) -> u64 {
+	((feerate_sat_per_1000_weight as u64 * weight) + 1000 - 1) / 1000
+}
+
 /// An interface to send a transaction to the Bitcoin network.
 pub trait BroadcasterInterface {
 	/// Sends a list of transactions out to (hopefully) be mined.

lightning/src/chain/onchaintx.rs

@@ -22,6 +22,7 @@ use bitcoin::hash_types::{Txid, BlockHash};
 use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature};
 use bitcoin::secp256k1;
 
+use crate::chain::chaininterface::compute_feerate_sat_per_1000_weight;
 use crate::sign::{ChannelSigner, EntropySource, SignerProvider};
 use crate::ln::msgs::DecodeError;
 use crate::ln::PaymentPreimage;
@@ -623,19 +624,31 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner> OnchainTxHandler<ChannelSigner>
 			return inputs.find_map(|input| match input {
 				// Commitment inputs with anchors support are the only untractable inputs supported
 				// thus far that require external funding.
-				PackageSolvingData::HolderFundingOutput(..) => {
+				PackageSolvingData::HolderFundingOutput(output) => {
 					debug_assert_eq!(tx.txid(), self.holder_commitment.trust().txid(),
 						"Holder commitment transaction mismatch");
+
+					let conf_target = ConfirmationTarget::HighPriority;
+					let package_target_feerate_sat_per_1000_weight = cached_request
+						.compute_package_feerate(fee_estimator, conf_target, force_feerate_bump);
+					if let Some(input_amount_sat) = output.funding_amount {
+						let fee_sat = input_amount_sat - tx.output.iter().map(|output| output.value).sum::<u64>();
+						if compute_feerate_sat_per_1000_weight(fee_sat, tx.weight() as u64) >=
+							 package_target_feerate_sat_per_1000_weight
+						{
+							log_debug!(logger, "Commitment transaction {} already meets required feerate {} sat/kW",
+								tx.txid(), package_target_feerate_sat_per_1000_weight);
+							return Some((new_timer, 0, OnchainClaim::Tx(tx.clone())));
+						}
+					}
+
 					// We'll locate an anchor output we can spend within the commitment transaction.
 					let funding_pubkey = &self.channel_transaction_parameters.holder_pubkeys.funding_pubkey;
 					match chan_utils::get_anchor_output(&tx, funding_pubkey) {
 						// An anchor output was found, so we should yield a funding event externally.
 						Some((idx, _)) => {
 							// TODO: Use a lower confirmation target when both our and the
 							// counterparty's latest commitment don't have any HTLCs present.
-							let conf_target = ConfirmationTarget::HighPriority;
-							let package_target_feerate_sat_per_1000_weight = cached_request
-								.compute_package_feerate(fee_estimator, conf_target, force_feerate_bump);
 							Some((
 								new_timer,
 								package_target_feerate_sat_per_1000_weight as u64,
@@ -739,6 +752,9 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner> OnchainTxHandler<ChannelSigner>
 			) {
 				req.set_timer(new_timer);
 				req.set_feerate(new_feerate);
+				// Once a pending claim has an id assigned, it remains fixed until the claim is
+				// satisfied, regardless of whether the claim switches between different variants of
+				// `OnchainClaim`.
 				let claim_id = match claim {
 					OnchainClaim::Tx(tx) => {
 						log_info!(logger, "Broadcasting onchain {}", log_tx!(tx));

lightning/src/chain/package.rs

@@ -429,7 +429,7 @@ impl Readable for HolderHTLCOutput {
 #[derive(Clone, PartialEq, Eq)]
 pub(crate) struct HolderFundingOutput {
 	funding_redeemscript: Script,
-	funding_amount: Option<u64>,
+	pub(crate) funding_amount: Option<u64>,
 	channel_type_features: ChannelTypeFeatures,
 }