multi: remove witness parameter from 'NewAltLeaf`

Since we're only ever passing nil (and we use the previous witness
in the script/burn key), we just remove the witness parameter
completely.

Author: gijswijs

asset/asset.go

@@ -1914,9 +1914,7 @@ type AltLeaf[T any] interface {
 }
 
 // NewAltLeaf instantiates a new valid AltLeaf.
-func NewAltLeaf(key ScriptKey, keyVersion ScriptVersion,
-	prevWitness []Witness) (*Asset, error) {
-
+func NewAltLeaf(key ScriptKey, keyVersion ScriptVersion) (*Asset, error) {
 	if key.PubKey == nil {
 		return nil, fmt.Errorf("script key must be non-nil")
 	}
@@ -1927,7 +1925,7 @@ func NewAltLeaf(key ScriptKey, keyVersion ScriptVersion,
 		Amount:              0,
 		LockTime:            0,
 		RelativeLockTime:    0,
-		PrevWitnesses:       prevWitness,
+		PrevWitnesses:       nil,
 		SplitCommitmentRoot: nil,
 		GroupKey:            nil,
 		ScriptKey:           key,
@@ -2106,9 +2104,7 @@ func CollectSTXO(outAsset *Asset) ([]AltLeaf[Asset], error) {
 
 		prevIdKey := DeriveBurnKey(*wit.PrevID)
 		scriptKey := NewScriptKey(prevIdKey)
-		altLeaf, err := NewAltLeaf(
-			scriptKey, ScriptV0, nil,
-		)
+		altLeaf, err := NewAltLeaf(scriptKey, ScriptV0)
 		if err != nil {
 			return nil, fmt.Errorf("error creating altLeaf: %w",
 				err)

asset/mock.go

@@ -678,12 +678,9 @@ func RandAssetWithValues(t testing.TB, genesis Genesis, groupKey *GroupKey,
 
 // RandAltLeaf generates a random Asset that is a valid AltLeaf.
 func RandAltLeaf(t testing.TB) *Asset {
-	randWitness := []Witness{
-		{TxWitness: test.RandTxWitnesses(t)},
-	}
 	randKey := RandScriptKey(t)
 	randVersion := ScriptVersion(test.RandInt[uint16]())
-	randLeaf, err := NewAltLeaf(randKey, randVersion, randWitness)
+	randLeaf, err := NewAltLeaf(randKey, randVersion)
 	require.NoError(t, err)
 	require.NoError(t, randLeaf.ValidateAltLeaf())
 

itest/psbt_test.go

@@ -650,7 +650,7 @@ func runPsbtInteractiveFullValueSendTest(ctxt context.Context, t *harnessTest,
 				prevIdKey := asset.DeriveBurnKey(*wit.PrevID)
 				scriptKey := asset.NewScriptKey(prevIdKey)
 				altLeaf, err := asset.NewAltLeaf(
-					scriptKey, asset.ScriptV0, nil,
+					scriptKey, asset.ScriptV0,
 				)
 				require.NoError(t.t, err)
 
@@ -2611,9 +2611,7 @@ func testPsbtSTXOExclusionProofs(t *harnessTest) {
 
 	// Create the minimal asset for which we expect to see the STXO
 	// exclusion.
-	minAsset, err := asset.NewAltLeaf(
-		expectedScriptKey, asset.ScriptV0, nil,
-	)
+	minAsset, err := asset.NewAltLeaf(expectedScriptKey, asset.ScriptV0)
 	require.NoError(t.t, err)
 
 	// We need to copy the base exclusion proof for each STXO because we'll

proof/append.go

@@ -174,7 +174,7 @@ func CreateTransitionProof(prevOut wire.OutPoint,
 			prevIdKey := asset.DeriveBurnKey(*wit.PrevID)
 			scriptKey := asset.NewScriptKey(prevIdKey)
 			spentAsset, err := asset.NewAltLeaf(
-				scriptKey, asset.ScriptV0, nil,
+				scriptKey, asset.ScriptV0,
 			)
 			if err != nil {
 				return nil, fmt.Errorf("error creating "+

proof/append_test.go

@@ -140,9 +140,7 @@ func runAppendTransitionTest(t *testing.T, assetType asset.Type, amt uint64,
 	// proofs will fail.
 	prevIdKey := asset.DeriveBurnKey(*newAsset.PrevWitnesses[0].PrevID)
 	scriptKey := asset.NewScriptKey(prevIdKey)
-	stxoAsset, err := asset.NewAltLeaf(
-		scriptKey, asset.ScriptV0, nil,
-	)
+	stxoAsset, err := asset.NewAltLeaf(scriptKey, asset.ScriptV0)
 	require.NoError(t, err)
 	stxoLeaf := asset.ToAltLeaves([]*asset.Asset{stxoAsset})
 	altLeaves = append(altLeaves, stxoLeaf...)
@@ -309,9 +307,7 @@ func runAppendTransitionTest(t *testing.T, assetType asset.Type, amt uint64,
 	// proofs will fail. With splits this is only needed for the root asset.
 	prevIdKey1 := asset.DeriveBurnKey(*split1Asset.PrevWitnesses[0].PrevID)
 	scriptKey1 := asset.NewScriptKey(prevIdKey1)
-	stxoAsset1, err := asset.NewAltLeaf(
-		scriptKey1, asset.ScriptV0, nil,
-	)
+	stxoAsset1, err := asset.NewAltLeaf(scriptKey1, asset.ScriptV0)
 	require.NoError(t, err)
 	stxoLeaf1 := asset.ToAltLeaves([]*asset.Asset{stxoAsset1})
 	split1AltLeaves = append(split1AltLeaves, stxoLeaf1...)

tapsend/send_test.go

@@ -388,7 +388,7 @@ func createPacket(t *testing.T, addr address.Tap, prevInput asset.PrevID,
 		for range numAltLeaves {
 			scriptKey := asset.NewScriptKey(test.RandPubKey(t))
 			baseLeaf, err := asset.NewAltLeaf(
-				scriptKey, asset.ScriptV0, nil,
+				scriptKey, asset.ScriptV0,
 			)
 			require.NoError(t, err)
 
@@ -1197,7 +1197,7 @@ var createOutputCommitmentsTestCases = []testCase{{
 
 		altLeafScriptKey := asset.NewScriptKey(test.RandPubKey(t))
 		newAltLeaf, err := asset.NewAltLeaf(
-			altLeafScriptKey, asset.ScriptV0, nil,
+			altLeafScriptKey, asset.ScriptV0,
 		)
 		require.NoError(t, err)