routing+routerrpc: notify full payment structures

This commit fixes the inconsistency between the payment state as
reported by routerrpc.SendPayment/routerrpc.TrackPayment and the main
rpc ListPayments call.

In addition to that, payment state changes are now sent out for every
state change. This opens the door to user interfaces giving more
feedback to the user about the payment process. This is especially
interesting for multi-part payments.

lntest/itest/lnd_test.go

@@ -14271,13 +14271,13 @@ func testHoldInvoicePersistence(net *lntest.NetworkHarness, t *harnessTest) {
 
 	// Wait for inlight status update.
 	for _, payStream := range paymentStreams {
-		status, err := payStream.Recv()
+		payment, err := payStream.Recv()
 		if err != nil {
 			t.Fatalf("Failed receiving status update: %v", err)
 		}
 
-		if status.State != routerrpc.PaymentState_IN_FLIGHT {
-			t.Fatalf("state not in flight: %v", status.State)
+		if payment.Status != lnrpc.Payment_IN_FLIGHT {
+			t.Fatalf("state not in flight: %v", payment.Status)
 		}
 	}
 
@@ -14355,7 +14355,7 @@ func testHoldInvoicePersistence(net *lntest.NetworkHarness, t *harnessTest) {
 	// Now after a restart, we must re-track the payments. We set up a
 	// goroutine for each to track thir status updates.
 	var (
-		statusUpdates []chan *routerrpc.PaymentStatus
+		statusUpdates []chan *lnrpc.Payment
 		wg            sync.WaitGroup
 		quit          = make(chan struct{})
 	)
@@ -14377,20 +14377,20 @@ func testHoldInvoicePersistence(net *lntest.NetworkHarness, t *harnessTest) {
 		}
 
 		// We set up a channel where we'll forward any status update.
-		upd := make(chan *routerrpc.PaymentStatus)
+		upd := make(chan *lnrpc.Payment)
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
 
 			for {
-				status, err := payStream.Recv()
+				payment, err := payStream.Recv()
 				if err != nil {
 					close(upd)
 					return
 				}
 
 				select {
-				case upd <- status:
+				case upd <- payment:
 				case <-quit:
 					return
 				}
@@ -14400,17 +14400,17 @@ func testHoldInvoicePersistence(net *lntest.NetworkHarness, t *harnessTest) {
 		statusUpdates = append(statusUpdates, upd)
 	}
 
-	// Wait for the infligt status update.
+	// Wait for the in-flight status update.
 	for _, upd := range statusUpdates {
 		select {
-		case status, ok := <-upd:
+		case payment, ok := <-upd:
 			if !ok {
-				t.Fatalf("failed getting status update")
+				t.Fatalf("failed getting payment update")
 			}
 
-			if status.State != routerrpc.PaymentState_IN_FLIGHT {
+			if payment.Status != lnrpc.Payment_IN_FLIGHT {
 				t.Fatalf("state not in in flight: %v",
-					status.State)
+					payment.Status)
 			}
 		case <-time.After(5 * time.Second):
 			t.Fatalf("in flight status not recevied")
@@ -14439,25 +14439,38 @@ func testHoldInvoicePersistence(net *lntest.NetworkHarness, t *harnessTest) {
 
 	// Make sure we get the expected status update.
 	for i, upd := range statusUpdates {
-		select {
-		case status, ok := <-upd:
-			if !ok {
-				t.Fatalf("failed getting status update")
-			}
+		// Read until the payment is in a terminal state.
+		var payment *lnrpc.Payment
+		for payment == nil {
+			select {
+			case p, ok := <-upd:
+				if !ok {
+					t.Fatalf("failed getting payment update")
+				}
 
-			if i%2 == 0 {
-				if status.State != routerrpc.PaymentState_SUCCEEDED {
-					t.Fatalf("state not suceeded : %v",
-						status.State)
-				}
-			} else {
-				if status.State != routerrpc.PaymentState_FAILED_INCORRECT_PAYMENT_DETAILS {
-					t.Fatalf("state not failed: %v",
-						status.State)
+				if p.Status == lnrpc.Payment_IN_FLIGHT {
+					continue
 				}
+
+				payment = p
+			case <-time.After(5 * time.Second):
+				t.Fatalf("in flight status not recevied")
+			}
+		}
+
+		// Assert terminal payment state.
+		if i%2 == 0 {
+			if payment.Status != lnrpc.Payment_SUCCEEDED {
+				t.Fatalf("state not suceeded : %v",
+					payment.Status)
+			}
+		} else {
+			if payment.FailureReason !=
+				lnrpc.PaymentFailureReason_FAILURE_REASON_INCORRECT_PAYMENT_DETAILS {
+
+				t.Fatalf("state not failed: %v",
+					payment.FailureReason)
 			}
-		case <-time.After(5 * time.Second):
-			t.Fatalf("in flight status not recevied")
 		}
 	}