lnwallet: add initial unit tests for musig2+tapscript root chans

lnwallet/channel_test.go

@@ -386,6 +386,12 @@ func TestSimpleAddSettleWorkflow(t *testing.T) {
 		)
 	})
 
+	t.Run("taproot with tapscript root", func(t *testing.T) {
+		flags := channeldb.SimpleTaprootFeatureBit |
+			channeldb.TapscriptRootBit
+		testAddSettleWorkflow(t, true, flags, false)
+	})
+
 	t.Run("storeFinalHtlcResolutions=true", func(t *testing.T) {
 		testAddSettleWorkflow(t, false, 0, true)
 	})
@@ -828,6 +834,16 @@ func TestForceClose(t *testing.T) {
 			anchorAmt:            anchorSize * 2,
 		})
 	})
+	t.Run("taproot with tapscript root", func(t *testing.T) {
+		testForceClose(t, &forceCloseTestCase{
+			chanType: channeldb.SingleFunderTweaklessBit |
+				channeldb.AnchorOutputsBit |
+				channeldb.SimpleTaprootFeatureBit |
+				channeldb.TapscriptRootBit,
+			expectedCommitWeight: input.TaprootCommitWeight,
+			anchorAmt:            anchorSize * 2,
+		})
+	})
 }
 
 type forceCloseTestCase struct {

lnwallet/test_utils.go

@@ -14,6 +14,7 @@ import (
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/lightningnetwork/lnd/channeldb"
+	"github.com/lightningnetwork/lnd/fn"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
 	"github.com/lightningnetwork/lnd/lnwallet/chainfee"
@@ -343,6 +344,21 @@ func CreateTestChannels(t *testing.T, chanType channeldb.ChannelType,
 		Packager:                channeldb.NewChannelPackager(shortChanID),
 	}
 
+	// If the channel type has a tapscript root, then we'll also specify
+	// one here to apply to both the channels.
+	if chanType.HasTapscriptRoot() {
+		var tapscriptRoot chainhash.Hash
+		_, err := io.ReadFull(rand.Reader, tapscriptRoot[:])
+		if err != nil {
+			return nil, nil, err
+		}
+
+		someRoot := fn.Some(tapscriptRoot)
+
+		aliceChannelState.TapscriptRoot = someRoot
+		bobChannelState.TapscriptRoot = someRoot
+	}
+
 	aliceSigner := input.NewMockSigner(aliceKeys, nil)
 	bobSigner := input.NewMockSigner(bobKeys, nil)