tapchannel: add test case for btc invoice paid with assets

In this commit we add an extra test case that checks if the
AuxInvoiceManager will reject the asset HTLCs that pay to a btc invoice.
We also do some housekeeping (commonly used vars, comments) across the
other test cases.

tapchannel/aux_invoice_manager_test.go

@@ -24,9 +24,6 @@ import (
 )
 
 const (
-	// The test channel ID to use across the test cases.
-	testChanID = 1234
-
 	// maxRandomInvoiceValueMSat is the maximum invoice value in mSAT to be
 	// generated by the property based tests.
 	maxRandomInvoiceValueMSat = 100_000_000_000
@@ -52,12 +49,20 @@ var (
 	// The node ID to be used for the RFQ peer.
 	testNodeID = route.Vertex{1, 2, 3}
 
+	// The asset rate value to use across tests.
 	assetRate = big.NewInt(100_000)
 
+	// The asset rate struct based on the assetRate value.
 	testAssetRate = rfqmath.FixedPoint[rfqmath.BigInt]{
 		Coefficient: rfqmath.NewBigInt(assetRate),
 		Scale:       0,
 	}
+
+	// The test RFQ ID to use across tests.
+	testRfqID = dummyRfqID(31)
+
+	// The test RFQ SCID that is derived from testRfqID.
+	testScid = testRfqID.Scid()
 )
 
 // mockRfqManager mocks the interface of the rfq manager required by the aux
@@ -293,7 +298,7 @@ func TestAuxInvoiceManager(t *testing.T) {
 				},
 			},
 			buyQuotes: map[rfq.SerialisedScid]rfqmsg.BuyAccept{
-				testChanID: {
+				testScid: {
 					Peer: testNodeID,
 				},
 			},
@@ -315,7 +320,7 @@ func TestAuxInvoiceManager(t *testing.T) {
 				},
 			},
 			buyQuotes: map[rfq.SerialisedScid]rfqmsg.BuyAccept{
-				testChanID: {
+				testScid: {
 					Peer: testNodeID,
 				},
 			},
@@ -335,7 +340,7 @@ func TestAuxInvoiceManager(t *testing.T) {
 								dummyAssetID(1),
 								3,
 							),
-						}, fn.Some(dummyRfqID(31)),
+						}, fn.Some(testRfqID),
 					),
 				},
 			},
@@ -345,7 +350,7 @@ func TestAuxInvoiceManager(t *testing.T) {
 				},
 			},
 			buyQuotes: rfq.BuyAcceptMap{
-				fn.Ptr(dummyRfqID(31)).Scid(): {
+				testScid: {
 					Peer: testNodeID,
 					AssetRate: rfqmsg.NewAssetRate(
 						testAssetRate, time.Now(),
@@ -368,7 +373,7 @@ func TestAuxInvoiceManager(t *testing.T) {
 								dummyAssetID(1),
 								4,
 							),
-						}, fn.Some(dummyRfqID(31)),
+						}, fn.Some(testRfqID),
 					),
 					ExitHtlcAmt: 1234,
 				},
@@ -379,14 +384,39 @@ func TestAuxInvoiceManager(t *testing.T) {
 				},
 			},
 			buyQuotes: rfq.BuyAcceptMap{
-				fn.Ptr(dummyRfqID(31)).Scid(): {
+				testScid: {
 					Peer: testNodeID,
 					AssetRate: rfqmsg.NewAssetRate(
 						testAssetRate, time.Now(),
 					),
 				},
 			},
 		},
+		{
+			name: "btc invoice, custom records",
+			requests: []lndclient.InvoiceHtlcModifyRequest{
+				{
+					Invoice: &lnrpc.Invoice{
+						ValueMsat:   10_000_000,
+						PaymentAddr: []byte{1, 1, 1},
+					},
+					WireCustomRecords: newWireCustomRecords(
+						t, []*rfqmsg.AssetBalance{
+							rfqmsg.NewAssetBalance(
+								dummyAssetID(1),
+								4,
+							),
+						}, fn.Some(testRfqID),
+					),
+					ExitHtlcAmt: 1234,
+				},
+			},
+			responses: []lndclient.InvoiceHtlcModifyResponse{
+				{
+					CancelSet: true,
+				},
+			},
+		},
 	}
 
 	for _, testCase := range testCases {
@@ -761,8 +791,8 @@ func testRouteHints() []*lnrpc.RouteHint {
 					NodeId: route.Vertex{1, 1, 1}.String(),
 				},
 				{
-					ChanId: 1234,
-					NodeId: route.Vertex{1, 2, 3}.String(),
+					ChanId: uint64(testScid),
+					NodeId: testNodeID.String(),
 				},
 			},
 		},