Don't auto-fail offers payments pre-HTLC lock in

Previously, we had a bug that particularly affected async payments where if an
outbound payment was in the state {Static}InvoiceReceived and there was a call
to process_pending_htlc_forwards, the payment would be automatically abandoned.
We would behave correctly and avoid abandoning if the payment was awaiting an
invoice, but not if the payment had an invoice but the HTLCs weren't yet locked
in.

Author: valentinewallace

lightning/src/ln/async_payments_tests.rs

@@ -240,6 +240,9 @@ fn pass_async_payments_oms(
 		.next_onion_message_for_peer(sender_node_id)
 		.unwrap();
 	sender.onion_messenger.handle_onion_message(always_online_node_id, &static_invoice_om);
+	// Check that the node will not lock in HTLCs yet.
+	sender.node.process_pending_htlc_forwards();
+	assert!(sender.node.get_and_clear_pending_msg_events().is_empty());
 
 	let held_htlc_available_om_0_1 =
 		sender.onion_messenger.next_onion_message_for_peer(always_online_node_id).unwrap();

lightning/src/ln/outbound_payment.rs

@@ -217,9 +217,13 @@ impl PendingOutboundPayment {
 			params.insert_previously_failed_blinded_path(blinded_tail);
 		}
 	}
-	fn is_awaiting_invoice(&self) -> bool {
+	// Used for payments to BOLT 12 offers where we are either waiting for an invoice or have an
+	// invoice but have not locked in HTLCs for the payment yet.
+	fn is_pre_htlc_lock_in(&self) -> bool {
 		match self {
-			PendingOutboundPayment::AwaitingInvoice { .. } => true,
+			PendingOutboundPayment::AwaitingInvoice { .. }
+			| PendingOutboundPayment::InvoiceReceived { .. }
+			| PendingOutboundPayment::StaticInvoiceReceived { .. } => true,
 			_ => false,
 		}
 	}
@@ -1368,7 +1372,7 @@ impl OutboundPayments {
 			let mut retain = true;
 			if !pmt.is_auto_retryable_now()
 				&& pmt.remaining_parts() == 0
-				&& !pmt.is_awaiting_invoice()
+				&& !pmt.is_pre_htlc_lock_in()
 			{
 				pmt.mark_abandoned(PaymentFailureReason::RetriesExhausted);
 				if let PendingOutboundPayment::Abandoned { payment_hash, reason, .. } = pmt {
@@ -1396,7 +1400,7 @@ impl OutboundPayments {
 				|| !pmt.is_auto_retryable_now()
 					&& pmt.remaining_parts() == 0
 					&& !pmt.is_fulfilled()
-					&& !pmt.is_awaiting_invoice()
+					&& !pmt.is_pre_htlc_lock_in()
 		})
 	}