Add payer_note argument for initiate_refund

bindings/ldk_node.udl

@@ -130,7 +130,7 @@ interface Bolt12Payment {
 	[Throws=NodeError]
 	Bolt12Invoice request_refund_payment([ByRef]Refund refund);
 	[Throws=NodeError]
-	Refund initiate_refund(u64 amount_msat, u32 expiry_secs, u64? quantity);
+	Refund initiate_refund(u64 amount_msat, u32 expiry_secs, string? payer_note, u64? quantity);
 };
 
 interface SpontaneousPayment {

src/payment/bolt12.rs

@@ -314,7 +314,8 @@ impl Bolt12Payment {
 
 	/// Returns a [`Refund`] object that can be used to offer a refund payment of the amount given.
 	pub fn initiate_refund(
-		&self, amount_msat: u64, expiry_secs: u32, quantity: Option<u64>,
+		&self, amount_msat: u64, expiry_secs: u32, payer_note: Option<String>,
+		quantity: Option<u64>,
 	) -> Result<Refund, Error> {
 		let mut random_bytes = [0u8; 32];
 		rand::thread_rng().fill_bytes(&mut random_bytes);
@@ -344,6 +345,10 @@ impl Bolt12Payment {
 			refund_builder = refund_builder.quantity(qty);
 		}
 
+		if let Some(note) = payer_note {
+			refund_builder = refund_builder.payer_note(note);
+		}
+
 		let refund = refund_builder.build().map_err(|e| {
 			log_error!(self.logger, "Failed to create refund: {:?}", e);
 			Error::RefundCreationFailed

tests/integration_tests_rust.rs

@@ -511,7 +511,8 @@ fn simple_bolt12_send_receive() {
 
 	// Now node_b refunds the amount node_a just overpaid.
 	let overpaid_amount = expected_amount_msat - offer_amount_msat;
-	let refund = node_b.bolt12_payment().initiate_refund(overpaid_amount, 3600, None).unwrap();
+	let refund =
+		node_b.bolt12_payment().initiate_refund(overpaid_amount, 3600, None, None).unwrap();
 	let invoice = node_a.bolt12_payment().request_refund_payment(&refund).unwrap();
 	expect_payment_received_event!(node_a, overpaid_amount);