fix(ledger): preallocate return structs

ledger/allegra/allegra.go

@@ -110,7 +110,7 @@ func (b *AllegraBlock) Transactions() []common.Transaction {
 }
 
 func (b *AllegraBlock) Utxorpc() *utxorpc.Block {
-	var txs []*utxorpc.Tx
+	txs := []*utxorpc.Tx{}
 	tmpHash, _ := hex.DecodeString(b.Hash())
 	for _, t := range b.Transactions() {
 		tx := t.Utxorpc()
@@ -274,7 +274,7 @@ func (t AllegraTransaction) Consumed() []common.TransactionInput {
 }
 
 func (t AllegraTransaction) Produced() []common.Utxo {
-	var ret []common.Utxo
+	ret := []common.Utxo{}
 	for idx, output := range t.Outputs() {
 		ret = append(
 			ret,

ledger/alonzo/alonzo.go

@@ -119,7 +119,7 @@ func (b *AlonzoBlock) Transactions() []common.Transaction {
 }
 
 func (b *AlonzoBlock) Utxorpc() *utxorpc.Block {
-	var txs []*utxorpc.Tx
+	txs := []*utxorpc.Tx{}
 	tmpHash, _ := hex.DecodeString(b.Hash())
 	for _, t := range b.Transactions() {
 		tx := t.Utxorpc()

ledger/babbage/babbage.go

@@ -120,7 +120,7 @@ func (b *BabbageBlock) Transactions() []common.Transaction {
 }
 
 func (b *BabbageBlock) Utxorpc() *utxorpc.Block {
-	var txs []*utxorpc.Tx
+	txs := []*utxorpc.Tx{}
 	tmpHash, _ := hex.DecodeString(b.Hash())
 	for _, t := range b.Transactions() {
 		tx := t.Utxorpc()
@@ -265,8 +265,9 @@ func (b *BabbageTransactionBody) TotalCollateral() uint64 {
 }
 
 func (b *BabbageTransactionBody) Utxorpc() *utxorpc.Tx {
-	var txi, txri []*utxorpc.TxInput
-	var txo []*utxorpc.TxOutput
+	txi := []*utxorpc.TxInput{}
+	txri := []*utxorpc.TxInput{}
+	txo := []*utxorpc.TxOutput{}
 	for _, i := range b.Inputs() {
 		input := i.Utxorpc()
 		txi = append(txi, input)

ledger/byron/byron.go

@@ -274,7 +274,7 @@ func (t *ByronTransaction) Consumed() []common.TransactionInput {
 }
 
 func (t *ByronTransaction) Produced() []common.Utxo {
-	var ret []common.Utxo
+	ret := []common.Utxo{}
 	for idx, output := range t.Outputs() {
 		ret = append(
 			ret,

ledger/byron/genesis.go

@@ -104,7 +104,7 @@ func (g *ByronGenesis) GenesisUtxos() ([]common.Utxo, error) {
 }
 
 func (g *ByronGenesis) avvmUtxos() ([]common.Utxo, error) {
-	var ret []common.Utxo
+	ret := []common.Utxo{}
 	for pubkey, amount := range g.AvvmDistr {
 		// Build address from redeem pubkey
 		pubkeyBytes, err := base64.URLEncoding.DecodeString(pubkey)
@@ -145,7 +145,7 @@ func (g *ByronGenesis) avvmUtxos() ([]common.Utxo, error) {
 }
 
 func (g *ByronGenesis) nonAvvmUtxos() ([]common.Utxo, error) {
-	var ret []common.Utxo
+	ret := []common.Utxo{}
 	for address, amount := range g.NonAvvmBalances {
 		tmpAddr, err := common.NewAddress(address)
 		if err != nil {

ledger/common/certs.go

@@ -1,4 +1,4 @@
-// Copyright 2024 Blink Labs Software
+// Copyright 2025 Blink Labs Software
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -480,7 +480,7 @@ func (c *MoveInstantaneousRewardsCertificate) UnmarshalCBOR(
 }
 
 func (c *MoveInstantaneousRewardsCertificate) Utxorpc() *utxorpc.Certificate {
-	var tmpMirTargets []*utxorpc.MirTarget
+	tmpMirTargets := []*utxorpc.MirTarget{}
 	for stakeCred, deltaCoin := range c.Reward.Rewards {
 		tmpMirTargets = append(
 			tmpMirTargets,

ledger/common/common.go

@@ -183,7 +183,7 @@ func (m MultiAsset[T]) MarshalJSON() ([]byte, error) {
 }
 
 func (m *MultiAsset[T]) Policies() []Blake2b224 {
-	var ret []Blake2b224
+	ret := []Blake2b224{}
 	for policyId := range m.data {
 		ret = append(ret, policyId)
 	}
@@ -195,7 +195,7 @@ func (m *MultiAsset[T]) Assets(policyId Blake2b224) [][]byte {
 	if !ok {
 		return nil
 	}
-	var ret [][]byte
+	ret := [][]byte{}
 	for assetName := range assets {
 		ret = append(ret, assetName.Bytes())
 	}

ledger/conway/conway.go

@@ -119,7 +119,7 @@ func (b *ConwayBlock) Transactions() []common.Transaction {
 }
 
 func (b *ConwayBlock) Utxorpc() *utxorpc.Block {
-	var txs []*utxorpc.Tx
+	txs := []*utxorpc.Tx{}
 	tmpHash, _ := hex.DecodeString(b.Hash())
 	for _, t := range b.Transactions() {
 		tx := t.Utxorpc()

ledger/mary/mary.go

@@ -112,7 +112,7 @@ func (b *MaryBlock) Transactions() []common.Transaction {
 }
 
 func (b *MaryBlock) Utxorpc() *utxorpc.Block {
-	var txs []*utxorpc.Tx
+	txs := []*utxorpc.Tx{}
 	tmpHash, _ := hex.DecodeString(b.Hash())
 	for _, t := range b.Transactions() {
 		tx := t.Utxorpc()
@@ -286,7 +286,7 @@ func (t MaryTransaction) Consumed() []common.TransactionInput {
 }
 
 func (t MaryTransaction) Produced() []common.Utxo {
-	var ret []common.Utxo
+	ret := []common.Utxo{}
 	for idx, output := range t.Outputs() {
 		ret = append(
 			ret,

ledger/mary/rules.go

@@ -48,7 +48,7 @@ func UtxoValidateOutputTooBigUtxo(
 	_ common.LedgerState,
 	_ common.ProtocolParameters,
 ) error {
-	var badOutputs []common.TransactionOutput
+	badOutputs := []common.TransactionOutput{}
 	for _, txOutput := range tx.Outputs() {
 		tmpOutput, ok := txOutput.(*MaryTransactionOutput)
 		if !ok {

ledger/shelley/rules.go

@@ -114,7 +114,7 @@ func UtxoValidateWrongNetwork(
 	pp common.ProtocolParameters,
 ) error {
 	networkId := ls.NetworkId()
-	var badAddrs []common.Address
+	badAddrs := []common.Address{}
 	for _, tmpOutput := range tx.Outputs() {
 		addr := tmpOutput.Address()
 		if addr.NetworkId() == networkId {
@@ -139,7 +139,7 @@ func UtxoValidateWrongNetworkWithdrawal(
 	pp common.ProtocolParameters,
 ) error {
 	networkId := ls.NetworkId()
-	var badAddrs []common.Address
+	badAddrs := []common.Address{}
 	for addr := range tx.Withdrawals() {
 		if addr.NetworkId() == networkId {
 			continue
@@ -224,7 +224,7 @@ func UtxoValidateOutputBootAddrAttrsTooBig(
 	ls common.LedgerState,
 	pp common.ProtocolParameters,
 ) error {
-	var badOutputs []common.TransactionOutput
+	badOutputs := []common.TransactionOutput{}
 	for _, tmpOutput := range tx.Outputs() {
 		addr := tmpOutput.Address()
 		if addr.Type() != common.AddressTypeByron {

ledger/shelley/shelley.go

@@ -110,7 +110,7 @@ func (b *ShelleyBlock) Transactions() []common.Transaction {
 }
 
 func (b *ShelleyBlock) Utxorpc() *utxorpc.Block {
-	var txs []*utxorpc.Tx
+	txs := []*utxorpc.Tx{}
 	tmpHash, _ := hex.DecodeString(b.Hash())
 	for _, t := range b.Transactions() {
 		tx := t.Utxorpc()
@@ -330,8 +330,8 @@ func (b *ShelleyTransactionBody) Donation() uint64 {
 }
 
 func (b *ShelleyTransactionBody) Utxorpc() *utxorpc.Tx {
-	var txi []*utxorpc.TxInput
-	var txo []*utxorpc.TxOutput
+	txi := []*utxorpc.TxInput{}
+	txo := []*utxorpc.TxOutput{}
 	for _, i := range b.Inputs() {
 		input := i.Utxorpc()
 		txi = append(txi, input)
@@ -626,7 +626,7 @@ func (t ShelleyTransaction) Consumed() []common.TransactionInput {
 }
 
 func (t ShelleyTransaction) Produced() []common.Utxo {
-	var ret []common.Utxo
+	ret := []common.Utxo{}
 	for idx, output := range t.Outputs() {
 		ret = append(
 			ret,

ledger/verify_block_body.go

@@ -390,7 +390,7 @@ func CalculateBlockBodyHash(txsRaw [][]string) ([]byte, error) {
 }
 
 func GetTxBodies(txsRaw [][]string) ([]BabbageTransactionBody, error) {
-	var bodies []BabbageTransactionBody
+	bodies := []BabbageTransactionBody{}
 	for index, tx := range txsRaw {
 		var tmp BabbageTransactionBody
 		bodyTmpHex := tx[0]