From 0a99bd9c52234eede2555cdfe5bc414c36f663c0 Mon Sep 17 00:00:00 2001
From: Devrandom <c1.devrandom@niftybox.net>
Date: Wed, 15 Jan 2020 10:33:38 -0800
Subject: [PATCH] refactor output sorting

---
 lightning/src/ln/channel.rs             | 21 +++++++++++----------
 lightning/src/util/transaction_utils.rs | 10 ----------
 2 files changed, 11 insertions(+), 20 deletions(-)

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index 6b6e52275..dcdde52a5 100644
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -814,7 +814,8 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			ins
 		};
 
-		let mut txouts: Vec<(TxOut, Option<(HTLCOutputInCommitment, Option<&HTLCSource>)>, Script)> = Vec::with_capacity(self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len() + 2);
+		let mut txouts: Vec<(TxOut, (Option<(HTLCOutputInCommitment, Option<&HTLCSource>)>, Script))> =
+			Vec::with_capacity(self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len() + 2);
 		let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
 
 		let dust_limit_satoshis = if local { self.our_dust_limit_satoshis } else { self.their_dust_limit_satoshis };
@@ -846,7 +847,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 						txouts.push((TxOut {
 							script_pubkey: script.to_v0_p2wsh(),
 							value: $htlc.amount_msat / 1000
-						}, Some((htlc_in_tx, $source)), script));
+						}, (Some((htlc_in_tx, $source)), script)));
 					} else {
 						log_trace!(self, "   ...including {} {} dust HTLC {} (hash {}) with value {} due to dust limit", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
 						included_dust_htlcs.push((htlc_in_tx, $source));
@@ -859,7 +860,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 						txouts.push((TxOut { // "received HTLC output"
 							script_pubkey: script.to_v0_p2wsh(),
 							value: $htlc.amount_msat / 1000
-						}, Some((htlc_in_tx, $source)), script));
+						}, (Some((htlc_in_tx, $source)), script)));
 					} else {
 						log_trace!(self, "   ...including {} {} dust HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
 						included_dust_htlcs.push((htlc_in_tx, $source));
@@ -965,7 +966,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			txouts.push((TxOut {
 				script_pubkey: script.to_v0_p2wsh(),
 				value: value_to_a as u64
-			}, None, script));
+			}, (None, script)));
 		}
 
 		if value_to_b >= (dust_limit_satoshis as i64) {
@@ -978,10 +979,10 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			txouts.push((TxOut {
 				script_pubkey: script,
 				value: value_to_b as u64
-			}, None, redeem_script));
+			}, (None, redeem_script)));
 		}
 
-		transaction_utils::sort_outputs2(&mut txouts, |a, b| {
+		transaction_utils::sort_outputs(&mut txouts, |(a, _), (b, _)| {
 			if let &Some(ref a_htlc) = a {
 				if let &Some(ref b_htlc) = b {
 					a_htlc.0.cltv_expiry.cmp(&b_htlc.0.cltv_expiry)
@@ -998,10 +999,10 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		let mut outputs: Vec<TxOut> = Vec::with_capacity(txouts.len());
 		let mut scripts: Vec<Script> = Vec::with_capacity(txouts.len());
 		let mut htlcs_included: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(txouts.len() + included_dust_htlcs.len());
-		for (idx, mut out) in txouts.drain(..).enumerate() {
-			outputs.push(out.0);
-			scripts.push(out.2);
-			if let Some((mut htlc, source_option)) = out.1.take() {
+		for (idx, (out, (mut htlc_data, script))) in txouts.drain(..).enumerate() {
+			outputs.push(out);
+			scripts.push(script);
+			if let Some((mut htlc, source_option)) = htlc_data.take() {
 				htlc.transaction_output_index = Some(idx as u32);
 				htlcs_included.push((htlc, source_option));
 			}
diff --git a/lightning/src/util/transaction_utils.rs b/lightning/src/util/transaction_utils.rs
index 95d14236e..a7c1e6bc6 100644
--- a/lightning/src/util/transaction_utils.rs
+++ b/lightning/src/util/transaction_utils.rs
@@ -12,16 +12,6 @@ pub fn sort_outputs<T, C : Fn(&T, &T) -> Ordering>(outputs: &mut Vec<(TxOut, T)>
 	});
 }
 
-pub fn sort_outputs2<T, T1, C : Fn(&T, &T) -> Ordering>(outputs: &mut Vec<(TxOut, T, T1)>, tie_breaker: C) {
-	outputs.sort_unstable_by(|a, b| {
-		a.0.value.cmp(&b.0.value).then_with(|| {
-			a.0.script_pubkey[..].cmp(&b.0.script_pubkey[..]).then_with(|| {
-				tie_breaker(&a.1, &b.1)
-			})
-		})
-	});
-}
-
 #[cfg(test)]
 mod tests {
 	use super::*;
-- 
2.39.5