Collapse NodeCustomMessageHandler enum into a struct

Remove the `Ignoring` variant now that the liquidity source is
always built, so the enum and its match arms are now pure
overhead. Replace it with a struct that holds the `LiquiditySource`
directly and have each trait method delegate straight to
`liquidity_manager()`.

Author: Camillarhi

src/builder.rs

@@ -1861,7 +1861,7 @@ fn build_with_store_internal(
 		let liquidity_source = runtime
 			.block_on(async move { liquidity_source_builder.build().await.map(Arc::new) })?;
 		let custom_message_handler =
-			Arc::new(NodeCustomMessageHandler::new_liquidity(Arc::clone(&liquidity_source)));
+			Arc::new(NodeCustomMessageHandler::new(Arc::clone(&liquidity_source)));
 
 		(liquidity_source, custom_message_handler)
 	};

src/message_handler.rs

@@ -18,24 +18,19 @@ use lightning_types::features::{InitFeatures, NodeFeatures};
 
 use crate::liquidity::LiquiditySource;
 
-pub(crate) enum NodeCustomMessageHandler<L: Deref>
+pub(crate) struct NodeCustomMessageHandler<L: Deref>
 where
 	L::Target: Logger,
 {
-	Ignoring,
-	Liquidity { liquidity_source: Arc<LiquiditySource<L>> },
+	liquidity_source: Arc<LiquiditySource<L>>,
 }
 
 impl<L: Deref> NodeCustomMessageHandler<L>
 where
 	L::Target: Logger,
 {
-	pub(crate) fn new_liquidity(liquidity_source: Arc<LiquiditySource<L>>) -> Self {
-		Self::Liquidity { liquidity_source }
-	}
-
-	pub(crate) fn new_ignoring() -> Self {
-		Self::Ignoring
+	pub(crate) fn new(liquidity_source: Arc<LiquiditySource<L>>) -> Self {
+		Self { liquidity_source }
 	}
 }
 
@@ -48,12 +43,7 @@ where
 	fn read<RD: LengthLimitedRead>(
 		&self, message_type: u16, buffer: &mut RD,
 	) -> Result<Option<Self::CustomMessage>, lightning::ln::msgs::DecodeError> {
-		match self {
-			Self::Ignoring => Ok(None),
-			Self::Liquidity { liquidity_source, .. } => {
-				liquidity_source.liquidity_manager().read(message_type, buffer)
-			},
-		}
+		self.liquidity_source.liquidity_manager().read(message_type, buffer)
 	}
 }
 
@@ -64,58 +54,28 @@ where
 	fn handle_custom_message(
 		&self, msg: Self::CustomMessage, sender_node_id: PublicKey,
 	) -> Result<(), lightning::ln::msgs::LightningError> {
-		match self {
-			Self::Ignoring => Ok(()), // Should be unreachable!() as the reader will return `None`
-			Self::Liquidity { liquidity_source, .. } => {
-				liquidity_source.liquidity_manager().handle_custom_message(msg, sender_node_id)
-			},
-		}
+		self.liquidity_source.liquidity_manager().handle_custom_message(msg, sender_node_id)
 	}
 
 	fn get_and_clear_pending_msg(&self) -> Vec<(PublicKey, Self::CustomMessage)> {
-		match self {
-			Self::Ignoring => Vec::new(),
-			Self::Liquidity { liquidity_source, .. } => {
-				liquidity_source.liquidity_manager().get_and_clear_pending_msg()
-			},
-		}
+		self.liquidity_source.liquidity_manager().get_and_clear_pending_msg()
 	}
 
 	fn provided_node_features(&self) -> NodeFeatures {
-		match self {
-			Self::Ignoring => NodeFeatures::empty(),
-			Self::Liquidity { liquidity_source, .. } => {
-				liquidity_source.liquidity_manager().provided_node_features()
-			},
-		}
+		self.liquidity_source.liquidity_manager().provided_node_features()
 	}
 
 	fn provided_init_features(&self, their_node_id: PublicKey) -> InitFeatures {
-		match self {
-			Self::Ignoring => InitFeatures::empty(),
-			Self::Liquidity { liquidity_source, .. } => {
-				liquidity_source.liquidity_manager().provided_init_features(their_node_id)
-			},
-		}
+		self.liquidity_source.liquidity_manager().provided_init_features(their_node_id)
 	}
 
 	fn peer_connected(
 		&self, their_node_id: PublicKey, msg: &lightning::ln::msgs::Init, inbound: bool,
 	) -> Result<(), ()> {
-		match self {
-			Self::Ignoring => Ok(()),
-			Self::Liquidity { liquidity_source, .. } => {
-				liquidity_source.liquidity_manager().peer_connected(their_node_id, msg, inbound)
-			},
-		}
+		self.liquidity_source.liquidity_manager().peer_connected(their_node_id, msg, inbound)
 	}
 
 	fn peer_disconnected(&self, their_node_id: PublicKey) {
-		match self {
-			Self::Ignoring => {},
-			Self::Liquidity { liquidity_source, .. } => {
-				liquidity_source.liquidity_manager().peer_disconnected(their_node_id)
-			},
-		}
+		self.liquidity_source.liquidity_manager().peer_disconnected(their_node_id)
 	}
 }