itest: formatting enhancements for tap payments

This commit mainly changes the returned type of the payment result for
asset payments. We create a struct TapPaymentResult which contains all
the related information for the outcome of an asset payment.

Author: GeorgeTsagk

itest/assets_test.go

@@ -1423,8 +1423,10 @@ func sendAssetKeySendPayment(t *testing.T, src, dst *HarnessNode, amt uint64,
 		return
 	}
 
-	result, _, err := getAssetPaymentResult(t, stream, false)
-	require.NoError(t, err)
+	tapResult := getAssetPaymentResult(t, stream, false)
+	require.NoError(t, tapResult.err)
+
+	result := tapResult.lndResult
 	if result.Status == lnrpc.Payment_FAILED {
 		t.Logf("Failure reason: %v", result.FailureReason)
 	}
@@ -1755,12 +1757,13 @@ func payInvoiceWithAssets(t *testing.T, payer, rfqPeer *HarnessNode,
 		sendReq.MaxShardSizeMsat = 80_000_000
 	}
 
-	var rfqBytes, peerPubKey []byte
+	var rfqBytes []byte
 	cfg.rfq.WhenSome(func(i rfqmsg.ID) {
 		rfqBytes = make([]byte, len(i[:]))
 		copy(rfqBytes, i[:])
 	})
 
+	var peerPubKey []byte
 	if rfqPeer != nil {
 		peerPubKey = rfqPeer.PubKey[:]
 	}
@@ -1785,7 +1788,7 @@ func payInvoiceWithAssets(t *testing.T, payer, rfqPeer *HarnessNode,
 
 	// If an error is returned by the RPC method (meaning the stream itself
 	// was established, no network or auth error), we expect the error to be
-	// returned on the first read on the stream.
+	// returned on the stream.
 	if cfg.errSubStr != "" {
 		msg, err := stream.Recv()
 
@@ -1804,14 +1807,18 @@ func payInvoiceWithAssets(t *testing.T, payer, rfqPeer *HarnessNode,
 		rateVal  rfqmath.FixedPoint[rfqmath.BigInt]
 	)
 
-	result, rateVal, err := getAssetPaymentResult(
+	tapResult := getAssetPaymentResult(
 		t, stream, cfg.payStatus == lnrpc.Payment_IN_FLIGHT,
 	)
-	require.NoError(t, err)
+	require.NoError(t, tapResult.err)
+
+	result := tapResult.lndResult
 	require.Equal(t, cfg.payStatus, result.Status)
 	require.Equal(t, cfg.failureReason, result.FailureReason)
 
 	amountMsat := lnwire.MilliSatoshi(decodedInvoice.NumMsat)
+
+	rateVal = tapResult.assetRate
 	milliSatsFP := rfqmath.MilliSatoshiToUnits(amountMsat, rateVal)
 	numUnits = milliSatsFP.ScaleTo(0).ToUint64()
 

itest/litd_accounts_test.go

@@ -445,10 +445,24 @@ func getPaymentResult(stream routerrpc.Router_SendPaymentV2Client,
 	}
 }
 
+// TapPaymentResult encapsulates all the information related to the outcome of
+// a tap asset payment. It may also contain an error, in which case the rest of
+// the values should be ignored, even if set.
+type TapPaymentResult struct {
+	// lndResult contains the lnd part of the payment result.
+	lndResult *lnrpc.Payment
+
+	// assetRate contains the asset rate that was used to convert the assets
+	// to sats.
+	assetRate rfqmath.FixedPoint[rfqmath.BigInt]
+
+	// err contains the returned error from the payment.
+	err error
+}
+
 func getAssetPaymentResult(t *testing.T,
 	s tapchannelrpc.TaprootAssetChannels_SendPaymentClient,
-	isHodl bool) (*lnrpc.Payment, rfqmath.FixedPoint[rfqmath.BigInt],
-	error) {
+	isHodl bool) TapPaymentResult {
 
 	// No idea why it makes a difference whether we wait before calling
 	// s.Recv() or not, but it does. Without the sleep, the test will fail
@@ -461,7 +475,11 @@ func getAssetPaymentResult(t *testing.T,
 	for {
 		msg, err := s.Recv()
 		if err != nil {
-			return nil, rateVal, err
+			return TapPaymentResult{
+				lndResult: nil,
+				assetRate: rateVal,
+				err:       err,
+			}
 		}
 
 		// Ignore RFQ quote acceptance messages read from the send
@@ -501,19 +519,29 @@ func getAssetPaymentResult(t *testing.T,
 
 		payment := msg.GetPaymentResult()
 		if payment == nil {
-			return nil, rateVal,
-				fmt.Errorf("unexpected message: %v", msg)
+			err := fmt.Errorf("unexpected message: %v", msg)
+			return TapPaymentResult{
+				lndResult: nil,
+				assetRate: rateVal,
+				err:       err,
+			}
+		}
+
+		result := TapPaymentResult{
+			lndResult: payment,
+			assetRate: rateVal,
+			err:       nil,
 		}
 
 		// If this is a hodl payment, then we'll return the first
 		// expected response. Otherwise, we'll wait until the in flight
 		// clears to we can observe the other payment states.
 		switch {
 		case isHodl:
-			return payment, rateVal, nil
+			return result
 
 		case payment.Status != lnrpc.Payment_IN_FLIGHT:
-			return payment, rateVal, nil
+			return result
 		}
 	}
 }