Move public_intro_node util into Blinded{Message,Payment}Path

Helps move towards making the BlindedPath struct private.

Author: valentinewallace

lightning/src/blinded_path/message.rs

@@ -103,6 +103,14 @@ impl BlindedMessagePath {
 			}
 		}
 	}
+
+	/// Returns the introduction [`NodeId`] of the blinded path, if it is publicly reachable (i.e.,
+	/// it is found in the network graph).
+	pub fn public_introduction_node_id<'a>(
+		&self, network_graph: &'a ReadOnlyNetworkGraph
+	) -> Option<&'a NodeId> {
+		self.0.public_introduction_node_id(network_graph)
+	}
 }
 
 /// An intermediate node, and possibly a short channel id leading to the next node.

lightning/src/blinded_path/mod.rs

@@ -164,9 +164,7 @@ impl BlindedPath {
 		})
 	}
 
-	/// Returns the introduction [`NodeId`] of the blinded path, if it is publicly reachable (i.e.,
-	/// it is found in the network graph).
-	pub fn public_introduction_node_id<'a>(
+	pub(super) fn public_introduction_node_id<'a>(
 		&self, network_graph: &'a ReadOnlyNetworkGraph
 	) -> Option<&'a NodeId> {
 		match &self.introduction_node {

lightning/src/blinded_path/payment.rs

@@ -24,6 +24,7 @@ use crate::ln::onion_utils;
 use crate::offers::invoice::BlindedPayInfo;
 use crate::offers::invoice_request::InvoiceRequestFields;
 use crate::offers::offer::OfferId;
+use crate::routing::gossip::{NodeId, ReadOnlyNetworkGraph};
 use crate::sign::{EntropySource, NodeSigner, Recipient};
 use crate::util::ser::{FixedLengthReader, LengthReadableArgs, HighZeroBytesDroppedBigSize, Readable, Writeable, Writer};
 
@@ -80,6 +81,14 @@ impl BlindedPaymentPath {
 			).map_err(|_| ())?,
 		})))
 	}
+
+	/// Returns the introduction [`NodeId`] of the blinded path, if it is publicly reachable (i.e.,
+	/// it is found in the network graph).
+	pub fn public_introduction_node_id<'a>(
+		&self, network_graph: &'a ReadOnlyNetworkGraph
+	) -> Option<&'a NodeId> {
+		self.0.public_introduction_node_id(network_graph)
+	}
 }
 
 /// An intermediate node, its outbound channel, and relay parameters.

lightning/src/ln/offers_tests.rs

@@ -137,7 +137,7 @@ fn announce_node_address<'a, 'b, 'c>(
 }
 
 fn resolve_introduction_node<'a, 'b, 'c>(node: &Node<'a, 'b, 'c>, path: &BlindedMessagePath) -> PublicKey {
-	path.0.public_introduction_node_id(&node.network_graph.read_only())
+	path.public_introduction_node_id(&node.network_graph.read_only())
 		.and_then(|node_id| node_id.as_pubkey().ok())
 		.unwrap()
 }

lightning/src/onion_message/messenger.rs

@@ -699,7 +699,6 @@ impl Destination {
 		if let Destination::BlindedPath(path) = self {
 			if let IntroductionNode::DirectedShortChannelId(..) = path.0.introduction_node {
 				if let Some(pubkey) = path
-					.0
 					.public_introduction_node_id(network_graph)
 					.and_then(|node_id| node_id.as_pubkey().ok())
 				{

lightning/src/routing/router.rs

@@ -1667,7 +1667,7 @@ where L::Target: Logger {
 					node_counters.node_counter_from_id(&NodeId::from_pubkey(&pubkey))
 				},
 				IntroductionNode::DirectedShortChannelId(direction, scid) => {
-					path.0.public_introduction_node_id(network_graph)
+					path.public_introduction_node_id(network_graph)
 						.map(|node_id_ref| *node_id_ref)
 						.or_else(|| {
 							first_hop_targets.iter().find(|(_, (channels, _))|
@@ -5692,7 +5692,7 @@ mod tests {
 							NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
 							payment_params.payee.blinded_route_hints().iter()
 								.find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
-								.and_then(|(_, p)| p.0.public_introduction_node_id(&network_graph))
+								.and_then(|(_, p)| p.public_introduction_node_id(&network_graph))
 								.copied()
 								.unwrap()
 						);
@@ -7899,7 +7899,7 @@ mod tests {
 		let final_hop = route.paths[0].hops.last().unwrap();
 		assert_eq!(
 			NodeId::from_pubkey(&final_hop.pubkey),
-			*blinded_path.0.public_introduction_node_id(&network_graph).unwrap()
+			*blinded_path.public_introduction_node_id(&network_graph).unwrap()
 		);
 		if tail.hops.len() > 1 {
 			assert_eq!(final_hop.fee_msat,