fix: ensure stage is changed if funds are locked, even in error case (#319)

protocol/xmrmaker/event.go

@@ -193,7 +193,9 @@ func (s *swapState) handleEvent(event Event) {
 		err := s.handleEventETHLocked(e)
 		if err != nil {
 			e.errCh <- fmt.Errorf("failed to handle EventETHLocked: %w", err)
-			return
+			if !s.fundsLocked {
+				return
+			}
 		}
 
 		err = s.setNextExpectedEvent(EventContractReadyType)

protocol/xmrmaker/swap_state.go

@@ -71,6 +71,8 @@ type swapState struct {
 
 	// tracks the state of the swap
 	nextExpectedEvent EventType
+	// set to true once funds are locked
+	fundsLocked bool
 
 	// channels
 
@@ -529,6 +531,7 @@ func (s *swapState) lockFunds(amount *coins.PiconeroAmount) (*message.NotifyXMRL
 	}
 	log.Infof("Successfully locked XMR funds: txID=%s address=%s block=%d",
 		transfer.TxID, swapDestAddr, transfer.Height)
+	s.fundsLocked = true
 
 	txID, err := types.HexToHash(transfer.TxID)
 	if err != nil {

protocol/xmrtaker/event.go

@@ -229,7 +229,9 @@ func (s *swapState) handleEvent(event Event) {
 		err := s.handleEventKeysReceived(e)
 		if err != nil {
 			e.errCh <- fmt.Errorf("failed to handle %s: %w", e.Type(), err)
-			return
+			if !s.fundsLocked {
+				return
+			}
 		}
 
 		err = s.setNextExpectedEvent(EventXMRLockedType)

protocol/xmrtaker/swap_state.go

@@ -77,6 +77,8 @@ type swapState struct {
 
 	// tracks the state of the swap
 	nextExpectedEvent EventType
+	// set to true once funds are locked
+	fundsLocked bool
 
 	// channels
 
@@ -613,6 +615,7 @@ func (s *swapState) lockAsset() (ethcommon.Hash, error) {
 		return ethcommon.Hash{}, fmt.Errorf("timeouts not found in transaction receipt's logs: %w", err)
 	}
 
+	s.fundsLocked = true
 	s.setTimeouts(t0, t1)
 
 	s.contractSwap = &contracts.SwapFactorySwap{