f always log when we skip fail/fulfill of an HTLC because we already did

Author: TheBlueMatt

lightning/src/ln/channelmanager.rs

@@ -2259,6 +2259,8 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 								error_data: None,
 							}
 						)
+					} else {
+						log_trace!(self.logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
 					}
 				},
 			};
@@ -2287,6 +2289,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 					session_priv_bytes.copy_from_slice(&session_priv[..]);
 					!self.pending_outbound_payments.lock().unwrap().remove(&session_priv_bytes)
 				} {
+					log_trace!(self.logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
 					return;
 				}
 				log_trace!(self.logger, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
@@ -2528,6 +2531,8 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 					pending_events.push(events::Event::PaymentSent {
 						payment_preimage
 					});
+				} else {
+					log_trace!(self.logger, "Received duplicative fulfill for HTLC with payment_preimage {}", log_bytes!(payment_preimage.0));
 				}
 			},
 			HTLCSource::PreviousHopData(hop_data) => {