peer: createTestPeerWithChannel returns a struct

The `createTestPeerWithChannel` function is made to return this newly
created struct and error.

This is useful because upcoming commits would require us returning more
objects from the function.

Signed-off-by: Ononiwu Maureen <maureen.ononiwu@outlook.com>

peer/brontide_test.go

@@ -48,11 +48,14 @@ func TestPeerChannelClosureShutdownResponseLinkRemoved(t *testing.T) {
 
 	mockSwitch := &mockMessageSwitch{}
 
-	alicePeer, bobChan, err := createTestPeerWithChannel(
+	harness, err := createTestPeerWithChannel(
 		t, notifier, broadcastTxChan, noUpdate, mockSwitch,
 	)
 	require.NoError(t, err, "unable to create test channels")
 
+	alicePeer := harness.peer
+	bobChan := harness.channel
+
 	chanPoint := bobChan.ChannelPoint()
 	chanID := lnwire.NewChanIDFromOutPoint(chanPoint)
 
@@ -96,11 +99,14 @@ func TestPeerChannelClosureAcceptFeeResponder(t *testing.T) {
 
 	mockSwitch := &mockMessageSwitch{}
 
-	alicePeer, bobChan, err := createTestPeerWithChannel(
+	harness, err := createTestPeerWithChannel(
 		t, notifier, broadcastTxChan, noUpdate, mockSwitch,
 	)
 	require.NoError(t, err, "unable to create test channels")
 
+	alicePeer := harness.peer
+	bobChan := harness.channel
+
 	chanPoint := bobChan.ChannelPoint()
 	chanID := lnwire.NewChanIDFromOutPoint(chanPoint)
 
@@ -201,11 +207,14 @@ func TestPeerChannelClosureAcceptFeeInitiator(t *testing.T) {
 
 	mockSwitch := &mockMessageSwitch{}
 
-	alicePeer, bobChan, err := createTestPeerWithChannel(
+	harness, err := createTestPeerWithChannel(
 		t, notifier, broadcastTxChan, noUpdate, mockSwitch,
 	)
 	require.NoError(t, err, "unable to create test channels")
 
+	bobChan := harness.channel
+	alicePeer := harness.peer
+
 	chanPoint := bobChan.ChannelPoint()
 	chanID := lnwire.NewChanIDFromOutPoint(chanPoint)
 	mockLink := newMockUpdateHandler(chanID)
@@ -325,11 +334,14 @@ func TestPeerChannelClosureFeeNegotiationsResponder(t *testing.T) {
 
 	mockSwitch := &mockMessageSwitch{}
 
-	alicePeer, bobChan, err := createTestPeerWithChannel(
+	harness, err := createTestPeerWithChannel(
 		t, notifier, broadcastTxChan, noUpdate, mockSwitch,
 	)
 	require.NoError(t, err, "unable to create test channels")
 
+	bobChan := harness.channel
+	alicePeer := harness.peer
+
 	chanPoint := bobChan.ChannelPoint()
 	chanID := lnwire.NewChanIDFromOutPoint(chanPoint)
 
@@ -512,11 +524,14 @@ func TestPeerChannelClosureFeeNegotiationsInitiator(t *testing.T) {
 
 	mockSwitch := &mockMessageSwitch{}
 
-	alicePeer, bobChan, err := createTestPeerWithChannel(
+	harness, err := createTestPeerWithChannel(
 		t, notifier, broadcastTxChan, noUpdate, mockSwitch,
 	)
 	require.NoError(t, err, "unable to create test channels")
 
+	alicePeer := harness.peer
+	bobChan := harness.channel
+
 	chanPoint := bobChan.ChannelPoint()
 	chanID := lnwire.NewChanIDFromOutPoint(chanPoint)
 	mockLink := newMockUpdateHandler(chanID)
@@ -840,7 +855,7 @@ func TestCustomShutdownScript(t *testing.T) {
 			mockSwitch := &mockMessageSwitch{}
 
 			// Open a channel.
-			alicePeer, bobChan, err := createTestPeerWithChannel(
+			harness, err := createTestPeerWithChannel(
 				t, notifier, broadcastTxChan, test.update,
 				mockSwitch,
 			)
@@ -848,13 +863,16 @@ func TestCustomShutdownScript(t *testing.T) {
 				t.Fatalf("unable to create test channels: %v", err)
 			}
 
+			alicePeer := harness.peer
+			bobChan := harness.channel
+
 			chanPoint := bobChan.ChannelPoint()
 			chanID := lnwire.NewChanIDFromOutPoint(chanPoint)
 			mockLink := newMockUpdateHandler(chanID)
 			mockSwitch.links = append(mockSwitch.links, mockLink)
 
-			// Request initiator to cooperatively close the channel, with
-			// a specified delivery address.
+			// Request initiator to cooperatively close the channel,
+			// with a specified delivery address.
 			updateChan := make(chan interface{}, 1)
 			errChan := make(chan error, 1)
 			closeCommand := htlcswitch.ChanClose{
@@ -1195,11 +1213,14 @@ func TestUpdateNextRevocation(t *testing.T) {
 	broadcastTxChan := make(chan *wire.MsgTx)
 	mockSwitch := &mockMessageSwitch{}
 
-	alicePeer, bobChan, err := createTestPeerWithChannel(
+	harness, err := createTestPeerWithChannel(
 		t, notifier, broadcastTxChan, noUpdate, mockSwitch,
 	)
 	require.NoError(err, "unable to create test channels")
 
+	bobChan := harness.channel
+	alicePeer := harness.peer
+
 	// testChannel is used to test the updateNextRevocation function.
 	testChannel := bobChan.State()
 
@@ -1432,11 +1453,13 @@ func TestStartupWriteMessageRace(t *testing.T) {
 
 	// createTestPeerWithChannel creates a peer and a channel with that
 	// peer.
-	peer, _, err := createTestPeerWithChannel(
+	harness, err := createTestPeerWithChannel(
 		t, notifier, broadcastTxChan, getChannels, mockSwitch,
 	)
 	require.NoError(t, err, "unable to create test channel")
 
+	peer := harness.peer
+
 	// Avoid the need to mock the channel graph by marking the channel
 	// borked. Borked channels still get a reestablish message sent on
 	// reconnect, while skipping channel graph checks and link creation.
@@ -1528,11 +1551,13 @@ func TestRemovePendingChannel(t *testing.T) {
 
 	// createTestPeerWithChannel creates a peer and a channel with that
 	// peer.
-	peer, _, err := createTestPeerWithChannel(
+	harness, err := createTestPeerWithChannel(
 		t, notifier, broadcastTxChan, noUpdate, mockSwitch,
 	)
 	require.NoError(t, err, "unable to create test channel")
 
+	peer := harness.peer
+
 	// Add a pending channel to the peer Alice.
 	errChan := make(chan error, 1)
 	pendingChanID := lnwire.ChannelID{1}