From: Valentine Wallace <vwallace@protonmail.com>
Date: Tue, 19 Mar 2024 18:58:43 +0000 (-0400)
Subject: Only write BlindedHopFeatures if any features are set.
X-Git-Tag: v0.0.123-beta~37^2
X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=caccb1cc21ad85d9a38f1876880843044b0ad6cf;p=rust-lightning

Only write BlindedHopFeatures if any features are set.

Minor space-saving optimization.
---

diff --git a/lightning/src/blinded_path/payment.rs b/lightning/src/blinded_path/payment.rs
index 0ed09a366..6467af568 100644
--- a/lightning/src/blinded_path/payment.rs
+++ b/lightning/src/blinded_path/payment.rs
@@ -120,11 +120,14 @@ impl TryFrom<CounterpartyForwardingInfo> for PaymentRelay {
 
 impl Writeable for ForwardTlvs {
 	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+		let features_opt =
+			if self.features == BlindedHopFeatures::empty() { None }
+			else { Some(&self.features) };
 		encode_tlv_stream!(w, {
 			(2, self.short_channel_id, required),
 			(10, self.payment_relay, required),
 			(12, self.payment_constraints, required),
-			(14, self.features, required)
+			(14, features_opt, option)
 		});
 		Ok(())
 	}