lnd.xprv/routing/payment_lifecycle_test.go

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package routing
import (
"crypto/rand"
"sync/atomic"
"testing"
"time"
"github.com/btcsuite/btcutil"
"github.com/go-errors/errors"
"github.com/lightningnetwork/lnd/channeldb"
"github.com/lightningnetwork/lnd/clock"
"github.com/lightningnetwork/lnd/htlcswitch"
"github.com/lightningnetwork/lnd/lntypes"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/lightningnetwork/lnd/routing/route"
"github.com/stretchr/testify/require"
)
const stepTimeout = 5 * time.Second
// createTestRoute builds a route a->b->c paying the given amt to c.
func createTestRoute(amt lnwire.MilliSatoshi,
aliasMap map[string]route.Vertex) (*route.Route, error) {
hopFee := lnwire.NewMSatFromSatoshis(3)
hop1 := aliasMap["b"]
hop2 := aliasMap["c"]
hops := []*route.Hop{
{
ChannelID: 1,
PubKeyBytes: hop1,
LegacyPayload: true,
AmtToForward: amt + hopFee,
},
{
ChannelID: 2,
PubKeyBytes: hop2,
LegacyPayload: true,
AmtToForward: amt,
},
}
// We create a simple route that we will supply every time the router
// requests one.
return route.NewRouteFromHops(
amt+2*hopFee, 100, aliasMap["a"], hops,
)
}
// paymentLifecycleTestCase contains the steps that we expect for a payment
// lifecycle test, and the routes that pathfinding should deliver.
type paymentLifecycleTestCase struct {
name string
// steps is a list of steps to perform during the testcase.
steps []string
// routes is the sequence of routes we will provide to the
// router when it requests a new route.
routes []*route.Route
// paymentErr is the error we expect our payment to fail with. This
// should be nil for tests with paymentSuccess steps and non-nil for
// payments with paymentError steps.
paymentErr error
}
const (
// routerInitPayment is a test step where we expect the router
// to call the InitPayment method on the control tower.
routerInitPayment = "Router:init-payment"
// routerRegisterAttempt is a test step where we expect the
// router to call the RegisterAttempt method on the control
// tower.
routerRegisterAttempt = "Router:register-attempt"
// routerSettleAttempt is a test step where we expect the
// router to call the SettleAttempt method on the control
// tower.
routerSettleAttempt = "Router:settle-attempt"
// routerFailAttempt is a test step where we expect the router
// to call the FailAttempt method on the control tower.
routerFailAttempt = "Router:fail-attempt"
// routerFailPayment is a test step where we expect the router
// to call the Fail method on the control tower.
routerFailPayment = "Router:fail-payment"
// routeRelease is a test step where we unblock pathfinding and
// allow it to respond to our test with a route.
routeRelease = "PaymentSession:release"
// sendToSwitchSuccess is a step where we expect the router to
// call send the payment attempt to the switch, and we will
// respond with a non-error, indicating that the payment
// attempt was successfully forwarded.
sendToSwitchSuccess = "SendToSwitch:success"
// sendToSwitchResultFailure is a step where we expect the
// router to send the payment attempt to the switch, and we
// will respond with a forwarding error. This can happen when
// forwarding fail on our local links.
sendToSwitchResultFailure = "SendToSwitch:failure"
// getPaymentResultSuccess is a test step where we expect the
// router to call the GetPaymentResult method, and we will
// respond with a successful payment result.
getPaymentResultSuccess = "GetPaymentResult:success"
// getPaymentResultTempFailure is a test step where we expect the
// router to call the GetPaymentResult method, and we will
// respond with a forwarding error, expecting the router to retry.
getPaymentResultTempFailure = "GetPaymentResult:temp-failure"
// getPaymentResultTerminalFailure is a test step where we
// expect the router to call the GetPaymentResult method, and
// we will respond with a terminal error, expecting the router
// to stop making payment attempts.
getPaymentResultTerminalFailure = "GetPaymentResult:terminal-failure"
// resendPayment is a test step where we manually try to resend
// the same payment, making sure the router responds with an
// error indicating that it is already in flight.
resendPayment = "ResendPayment"
// startRouter is a step where we manually start the router,
// used to test that it automatically will resume payments at
// startup.
startRouter = "StartRouter"
// stopRouter is a test step where we manually make the router
// shut down.
stopRouter = "StopRouter"
// paymentSuccess is a step where assert that we receive a
// successful result for the original payment made.
paymentSuccess = "PaymentSuccess"
// paymentError is a step where assert that we receive an error
// for the original payment made.
paymentError = "PaymentError"
// resentPaymentSuccess is a step where assert that we receive
// a successful result for a payment that was resent.
resentPaymentSuccess = "ResentPaymentSuccess"
// resentPaymentError is a step where assert that we receive an
// error for a payment that was resent.
resentPaymentError = "ResentPaymentError"
)
// TestRouterPaymentStateMachine tests that the router interacts as expected
// with the ControlTower during a payment lifecycle, such that it payment
// attempts are not sent twice to the switch, and results are handled after a
// restart.
func TestRouterPaymentStateMachine(t *testing.T) {
t.Parallel()
const startingBlockHeight = 101
// Setup two simple channels such that we can mock sending along this
// route.
chanCapSat := btcutil.Amount(100000)
testChannels := []*testChannel{
symmetricTestChannel("a", "b", chanCapSat, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
MaxHTLC: lnwire.NewMSatFromSatoshis(chanCapSat),
}, 1),
symmetricTestChannel("b", "c", chanCapSat, &testChannelPolicy{
Expiry: 144,
FeeRate: 400,
MinHTLC: 1,
MaxHTLC: lnwire.NewMSatFromSatoshis(chanCapSat),
}, 2),
}
testGraph, err := createTestGraphFromChannels(testChannels, "a")
if err != nil {
t.Fatalf("unable to create graph: %v", err)
}
defer testGraph.cleanUp()
paymentAmt := lnwire.NewMSatFromSatoshis(1000)
// We create a simple route that we will supply every time the router
// requests one.
rt, err := createTestRoute(paymentAmt, testGraph.aliasMap)
if err != nil {
t.Fatalf("unable to create route: %v", err)
}
halfShard, err := createTestRoute(paymentAmt/2, testGraph.aliasMap)
require.NoError(t, err, "unable to create half route")
shard, err := createTestRoute(paymentAmt/4, testGraph.aliasMap)
if err != nil {
t.Fatalf("unable to create route: %v", err)
}
tests := []paymentLifecycleTestCase{
{
// Tests a normal payment flow that succeeds.
name: "single shot success",
steps: []string{
routerInitPayment,
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
getPaymentResultSuccess,
routerSettleAttempt,
paymentSuccess,
},
routes: []*route.Route{rt},
},
{
// A payment flow with a failure on the first attempt,
// but that succeeds on the second attempt.
name: "single shot retry",
steps: []string{
routerInitPayment,
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// Make the first sent attempt fail.
getPaymentResultTempFailure,
routerFailAttempt,
// The router should retry.
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// Make the second sent attempt succeed.
getPaymentResultSuccess,
routerSettleAttempt,
paymentSuccess,
},
routes: []*route.Route{rt, rt},
},
{
// A payment flow with a forwarding failure first time
// sending to the switch, but that succeeds on the
// second attempt.
name: "single shot switch failure",
steps: []string{
routerInitPayment,
routeRelease,
routerRegisterAttempt,
// Make the first sent attempt fail.
sendToSwitchResultFailure,
routerFailAttempt,
// The router should retry.
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// Make the second sent attempt succeed.
getPaymentResultSuccess,
routerSettleAttempt,
paymentSuccess,
},
routes: []*route.Route{rt, rt},
},
{
// A payment that fails on the first attempt, and has
// only one route available to try. It will therefore
// fail permanently.
name: "single shot route fails",
steps: []string{
routerInitPayment,
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// Make the first sent attempt fail.
getPaymentResultTempFailure,
routerFailAttempt,
routeRelease,
// Since there are no more routes to try, the
// payment should fail.
routerFailPayment,
paymentError,
},
routes: []*route.Route{rt},
paymentErr: channeldb.FailureReasonNoRoute,
},
{
// We expect the payment to fail immediately if we have
// no routes to try.
name: "single shot no route",
steps: []string{
routerInitPayment,
routeRelease,
routerFailPayment,
paymentError,
},
routes: []*route.Route{},
paymentErr: channeldb.FailureReasonNoRoute,
},
{
// A normal payment flow, where we attempt to resend
// the same payment after each step. This ensures that
// the router don't attempt to resend a payment already
// in flight.
name: "single shot resend",
steps: []string{
routerInitPayment,
routeRelease,
routerRegisterAttempt,
// Manually resend the payment, the router
// should attempt to init with the control
// tower, but fail since it is already in
// flight.
resendPayment,
routerInitPayment,
resentPaymentError,
// The original payment should proceed as
// normal.
sendToSwitchSuccess,
// Again resend the payment and assert it's not
// allowed.
resendPayment,
routerInitPayment,
resentPaymentError,
// Notify about a success for the original
// payment.
getPaymentResultSuccess,
routerSettleAttempt,
// Now that the original payment finished,
// resend it again to ensure this is not
// allowed.
resendPayment,
routerInitPayment,
resentPaymentError,
paymentSuccess,
},
routes: []*route.Route{rt},
},
{
// Tests that the router is able to handle the
// receieved payment result after a restart.
name: "single shot restart",
steps: []string{
routerInitPayment,
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// Shut down the router. The original caller
// should get notified about this.
stopRouter,
paymentError,
// Start the router again, and ensure the
// router registers the success with the
// control tower.
startRouter,
getPaymentResultSuccess,
routerSettleAttempt,
},
routes: []*route.Route{rt},
paymentErr: ErrRouterShuttingDown,
},
{
// Tests that we are allowed to resend a payment after
// it has permanently failed.
name: "single shot resend fail",
steps: []string{
routerInitPayment,
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// Resending the payment at this stage should
// not be allowed.
resendPayment,
routerInitPayment,
resentPaymentError,
// Make the first attempt fail.
getPaymentResultTempFailure,
routerFailAttempt,
// Since we have no more routes to try, the
// original payment should fail.
routeRelease,
routerFailPayment,
paymentError,
// Now resend the payment again. This should be
// allowed, since the payment has failed.
resendPayment,
routerInitPayment,
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
getPaymentResultSuccess,
routerSettleAttempt,
resentPaymentSuccess,
},
routes: []*route.Route{rt},
paymentErr: channeldb.FailureReasonNoRoute,
},
// =====================================
// || MPP scenarios ||
// =====================================
{
// Tests a simple successful MP payment of 4 shards.
name: "MP success",
steps: []string{
routerInitPayment,
// shard 0
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 1
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 2
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 3
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// All shards succeed.
getPaymentResultSuccess,
getPaymentResultSuccess,
getPaymentResultSuccess,
getPaymentResultSuccess,
// Router should settle them all.
routerSettleAttempt,
routerSettleAttempt,
routerSettleAttempt,
routerSettleAttempt,
// And the final result is obviously
// successful.
paymentSuccess,
},
routes: []*route.Route{shard, shard, shard, shard},
},
{
// An MP payment scenario where we need several extra
// attempts before the payment finally settle.
name: "MP failed shards",
steps: []string{
routerInitPayment,
// shard 0
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 1
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 2
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 3
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// First two shards fail, two new ones are sent.
getPaymentResultTempFailure,
getPaymentResultTempFailure,
routerFailAttempt,
routerFailAttempt,
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// The four shards settle.
getPaymentResultSuccess,
getPaymentResultSuccess,
getPaymentResultSuccess,
getPaymentResultSuccess,
routerSettleAttempt,
routerSettleAttempt,
routerSettleAttempt,
routerSettleAttempt,
// Overall payment succeeds.
paymentSuccess,
},
routes: []*route.Route{
shard, shard, shard, shard, shard, shard,
},
},
{
// An MP payment scenario where one of the shards fails,
// but we still receive a single success shard.
name: "MP one shard success",
steps: []string{
routerInitPayment,
// shard 0
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 1
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 0 fails, and should be failed by the
// router.
getPaymentResultTempFailure,
routerFailAttempt,
// We will try one more shard because we haven't
// sent the full payment amount.
routeRelease,
// The second shard succeed against all odds,
// making the overall payment succeed.
getPaymentResultSuccess,
routerSettleAttempt,
paymentSuccess,
},
routes: []*route.Route{halfShard, halfShard},
},
{
// An MP payment scenario a shard fail with a terminal
// error, causing the router to stop attempting.
name: "MP terminal",
steps: []string{
routerInitPayment,
// shard 0
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 1
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 2
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 3
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// The first shard fail with a terminal error.
getPaymentResultTerminalFailure,
routerFailAttempt,
routerFailPayment,
// Remaining 3 shards fail.
getPaymentResultTempFailure,
getPaymentResultTempFailure,
getPaymentResultTempFailure,
routerFailAttempt,
routerFailAttempt,
routerFailAttempt,
// Payment fails.
paymentError,
},
routes: []*route.Route{
shard, shard, shard, shard, shard, shard,
},
paymentErr: channeldb.FailureReasonPaymentDetails,
},
{
// A MP payment scenario when our path finding returns
// after we've just received a terminal failure, and
// attempts to dispatch a new shard. Testing that we
// correctly abandon the shard and conclude the payment.
name: "MP path found after failure",
steps: []string{
routerInitPayment,
// shard 0
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// The first shard fail with a terminal error.
getPaymentResultTerminalFailure,
routerFailAttempt,
routerFailPayment,
// shard 1 fails because we've had a terminal
// failure.
routeRelease,
routerRegisterAttempt,
// Payment fails.
paymentError,
},
routes: []*route.Route{
shard, shard,
},
paymentErr: channeldb.FailureReasonPaymentDetails,
},
{
// A MP payment scenario when our path finding returns
// after we've just received a terminal failure, and
// we have another shard still in flight.
name: "MP shard in flight after terminal",
steps: []string{
routerInitPayment,
// shard 0
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 1
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// shard 2
routeRelease,
routerRegisterAttempt,
sendToSwitchSuccess,
// We find a path for another shard.
routeRelease,
// shard 0 fails with a terminal error.
getPaymentResultTerminalFailure,
routerFailAttempt,
routerFailPayment,
// We try to register our final shard after
// processing a terminal failure.
routerRegisterAttempt,
// Our in-flight shards fail.
getPaymentResultTempFailure,
getPaymentResultTempFailure,
routerFailAttempt,
routerFailAttempt,
// Payment fails.
paymentError,
},
routes: []*route.Route{
shard, shard, shard, shard,
},
paymentErr: channeldb.FailureReasonPaymentDetails,
},
}
for _, test := range tests {
test := test
t.Run(test.name, func(t *testing.T) {
testPaymentLifecycle(
t, test, paymentAmt, startingBlockHeight,
testGraph,
)
})
}
}
func testPaymentLifecycle(t *testing.T, test paymentLifecycleTestCase,
paymentAmt lnwire.MilliSatoshi, startingBlockHeight uint32,
testGraph *testGraphInstance) {
// Create a mock control tower with channels set up, that we use to
// synchronize and listen for events.
control := makeMockControlTower()
control.init = make(chan initArgs)
control.registerAttempt = make(chan registerAttemptArgs)
control.settleAttempt = make(chan settleAttemptArgs)
control.failAttempt = make(chan failAttemptArgs)
control.failPayment = make(chan failPaymentArgs)
control.fetchInFlight = make(chan struct{})
// setupRouter is a helper method that creates and starts the router in
// the desired configuration for this test.
setupRouter := func() (*ChannelRouter, chan error,
chan *htlcswitch.PaymentResult) {
chain := newMockChain(startingBlockHeight)
chainView := newMockChainView(chain)
// We set uo the use the following channels and a mock Payer to
// synchonize with the interaction to the Switch.
sendResult := make(chan error)
paymentResult := make(chan *htlcswitch.PaymentResult)
payer := &mockPayer{
sendResult: sendResult,
paymentResult: paymentResult,
}
router, err := New(Config{
Graph: testGraph.graph,
Chain: chain,
ChainView: chainView,
Control: control,
SessionSource: &mockPaymentSessionSource{},
MissionControl: &mockMissionControl{},
Payer: payer,
ChannelPruneExpiry: time.Hour * 24,
GraphPruneInterval: time.Hour * 2,
QueryBandwidth: func(e *channeldb.ChannelEdgeInfo) lnwire.MilliSatoshi {
return lnwire.NewMSatFromSatoshis(e.Capacity)
},
NextPaymentID: func() (uint64, error) {
next := atomic.AddUint64(&uniquePaymentID, 1)
return next, nil
},
Clock: clock.NewTestClock(time.Unix(1, 0)),
})
if err != nil {
t.Fatalf("unable to create router %v", err)
}
// On startup, the router should fetch all pending payments
// from the ControlTower, so assert that here.
errCh := make(chan error)
go func() {
close(errCh)
select {
case <-control.fetchInFlight:
return
case <-time.After(1 * time.Second):
errCh <- errors.New("router did not fetch in flight " +
"payments")
}
}()
if err := router.Start(); err != nil {
t.Fatalf("unable to start router: %v", err)
}
select {
case err := <-errCh:
if err != nil {
t.Fatalf("error in anonymous goroutine: %s", err)
}
case <-time.After(1 * time.Second):
t.Fatalf("did not fetch in flight payments at startup")
}
return router, sendResult, paymentResult
}
router, sendResult, getPaymentResult := setupRouter()
defer func() {
if err := router.Stop(); err != nil {
t.Fatal(err)
}
}()
// Craft a LightningPayment struct.
var preImage lntypes.Preimage
if _, err := rand.Read(preImage[:]); err != nil {
t.Fatalf("unable to generate preimage")
}
payHash := preImage.Hash()
payment := LightningPayment{
Target: testGraph.aliasMap["c"],
Amount: paymentAmt,
FeeLimit: noFeeLimit,
paymentHash: &payHash,
}
// Setup our payment session source to block on release of
// routes.
routeChan := make(chan struct{})
router.cfg.SessionSource = &mockPaymentSessionSource{
routes: test.routes,
routeRelease: routeChan,
}
router.cfg.MissionControl = &mockMissionControl{}
// Send the payment. Since this is new payment hash, the
// information should be registered with the ControlTower.
paymentResult := make(chan error)
done := make(chan struct{})
go func() {
_, _, err := router.SendPayment(&payment)
paymentResult <- err
close(done)
}()
var resendResult chan error
for _, step := range test.steps {
switch step {
case routerInitPayment:
var args initArgs
select {
case args = <-control.init:
case <-time.After(stepTimeout):
t.Fatalf("no init payment with control")
}
if args.c == nil {
t.Fatalf("expected non-nil CreationInfo")
}
case routeRelease:
select {
case <-routeChan:
case <-time.After(stepTimeout):
t.Fatalf("no route requested")
}
// In this step we expect the router to make a call to
// register a new attempt with the ControlTower.
case routerRegisterAttempt:
var args registerAttemptArgs
select {
case args = <-control.registerAttempt:
case <-time.After(stepTimeout):
t.Fatalf("attempt not registered " +
"with control")
}
if args.a == nil {
t.Fatalf("expected non-nil AttemptInfo")
}
// In this step we expect the router to call the
// ControlTower's SettleAttempt method with the preimage.
case routerSettleAttempt:
select {
case <-control.settleAttempt:
case <-time.After(stepTimeout):
t.Fatalf("attempt settle not " +
"registered with control")
}
// In this step we expect the router to call the
// ControlTower's FailAttempt method with a HTLC fail
// info.
case routerFailAttempt:
select {
case <-control.failAttempt:
case <-time.After(stepTimeout):
t.Fatalf("attempt fail not " +
"registered with control")
}
// In this step we expect the router to call the
// ControlTower's Fail method, to indicate that the
// payment failed.
case routerFailPayment:
select {
case <-control.failPayment:
case <-time.After(stepTimeout):
t.Fatalf("payment fail not " +
"registered with control")
}
// In this step we expect the SendToSwitch method to be
// called, and we respond with a nil-error.
case sendToSwitchSuccess:
select {
case sendResult <- nil:
case <-time.After(stepTimeout):
t.Fatalf("unable to send result")
}
// In this step we expect the SendToSwitch method to be
// called, and we respond with a forwarding error
case sendToSwitchResultFailure:
select {
case sendResult <- htlcswitch.NewForwardingError(
&lnwire.FailTemporaryChannelFailure{},
1,
):
case <-time.After(stepTimeout):
t.Fatalf("unable to send result")
}
// In this step we expect the GetPaymentResult method
// to be called, and we respond with the preimage to
// complete the payment.
case getPaymentResultSuccess:
select {
case getPaymentResult <- &htlcswitch.PaymentResult{
Preimage: preImage,
}:
case <-time.After(stepTimeout):
t.Fatalf("unable to send result")
}
// In this state we expect the GetPaymentResult method
// to be called, and we respond with a forwarding
// error, indicating that the router should retry.
case getPaymentResultTempFailure:
failure := htlcswitch.NewForwardingError(
&lnwire.FailTemporaryChannelFailure{},
1,
)
select {
case getPaymentResult <- &htlcswitch.PaymentResult{
Error: failure,
}:
case <-time.After(stepTimeout):
t.Fatalf("unable to get result")
}
// In this state we expect the router to call the
// GetPaymentResult method, and we will respond with a
// terminal error, indiating the router should stop
// making payment attempts.
case getPaymentResultTerminalFailure:
failure := htlcswitch.NewForwardingError(
&lnwire.FailIncorrectDetails{},
1,
)
select {
case getPaymentResult <- &htlcswitch.PaymentResult{
Error: failure,
}:
case <-time.After(stepTimeout):
t.Fatalf("unable to get result")
}
// In this step we manually try to resend the same
// payment, making sure the router responds with an
// error indicating that it is already in flight.
case resendPayment:
resendResult = make(chan error)
go func() {
_, _, err := router.SendPayment(&payment)
resendResult <- err
}()
// In this step we manually stop the router.
case stopRouter:
// On shutdown, the switch closes our result channel.
// Mimic this behavior in our mock.
close(getPaymentResult)
if err := router.Stop(); err != nil {
t.Fatalf("unable to restart: %v", err)
}
// In this step we manually start the router.
case startRouter:
router, sendResult, getPaymentResult = setupRouter()
// In this state we expect to receive an error for the
// original payment made.
case paymentError:
require.Error(t, test.paymentErr,
"paymentError not set")
select {
case err := <-paymentResult:
require.Equal(t, test.paymentErr, err)
case <-time.After(stepTimeout):
t.Fatalf("got no payment result")
}
// In this state we expect the original payment to
// succeed.
case paymentSuccess:
require.Nil(t, test.paymentErr)
select {
case err := <-paymentResult:
if err != nil {
t.Fatalf("did not expect "+
"error %v", err)
}
case <-time.After(stepTimeout):
t.Fatalf("got no payment result")
}
// In this state we expect to receive an error for the
// resent payment made.
case resentPaymentError:
select {
case err := <-resendResult:
if err == nil {
t.Fatalf("expected error")
}
case <-time.After(stepTimeout):
t.Fatalf("got no payment result")
}
// In this state we expect the resent payment to
// succeed.
case resentPaymentSuccess:
select {
case err := <-resendResult:
if err != nil {
t.Fatalf("did not expect error %v", err)
}
case <-time.After(stepTimeout):
t.Fatalf("got no payment result")
}
default:
t.Fatalf("unknown step %v", step)
}
}
select {
case <-done:
case <-time.After(testTimeout):
t.Fatalf("SendPayment didn't exit")
}
}