Extend ethclient test, implement new TxID spec

- Implement new TxID spec that distinguishes L1UserTx and L1CoordinatorTx
- Replace some type []*Foo by []Foo
- Fix HistoryDB & L2DB bug: in case of error, a rollback was applied and the returned error was nil
- Reorder inserts in historydb.NewHistoryDB() to follow foreign key dependencies
- Add initial synchronizer test with test.Client (for now, only tested l1UserTxs, blocks, addToken)
- Update L1UserTx event in test.Client

batchbuilder/batchbuilder.go

@@ -51,7 +51,7 @@ func (bb *BatchBuilder) Reset(batchNum common.BatchNum, fromSynchronizer bool) e
 }
 
 // BuildBatch takes the transactions and returns the common.ZKInputs of the next batch
-func (bb *BatchBuilder) BuildBatch(configBatch *ConfigBatch, l1usertxs, l1coordinatortxs []*common.L1Tx, pooll2txs []*common.PoolL2Tx, tokenIDs []common.TokenID) (*common.ZKInputs, error) {
+func (bb *BatchBuilder) BuildBatch(configBatch *ConfigBatch, l1usertxs, l1coordinatortxs []common.L1Tx, pooll2txs []common.PoolL2Tx, tokenIDs []common.TokenID) (*common.ZKInputs, error) {
 	zkInputs, _, err := bb.localStateDB.ProcessTxs(l1usertxs, l1coordinatortxs, pooll2txs)
 	if err != nil {
 		return nil, err

common/l1tx.go

@@ -81,24 +81,39 @@ func NewL1Tx(l1Tx *L1Tx) (*L1Tx, error) {
 	}
 	l1Tx.Type = txType
 
-	var txid [TxIDLen]byte
-	if !l1Tx.UserOrigin {
-		txid[0] = TxIDPrefixL1CoordTx
-	}
-	var toForgeL1TxsNumBytes [8]byte
-	var toForge uint64 = 0
-	if l1Tx.ToForgeL1TxsNum != nil {
-		toForge = uint64(*l1Tx.ToForgeL1TxsNum)
+	txID, err := l1Tx.CalcTxID()
+	if err != nil {
+		return nil, err
 	}
-	binary.BigEndian.PutUint64(toForgeL1TxsNumBytes[:], toForge)
-	copy(txid[1:9], toForgeL1TxsNumBytes[:])
+	l1Tx.TxID = *txID
+
+	return l1Tx, nil
+}
 
+func (l1Tx *L1Tx) CalcTxID() (*TxID, error) {
+	var txID TxID
+	if l1Tx.UserOrigin {
+		if l1Tx.ToForgeL1TxsNum == nil {
+			return nil, fmt.Errorf("L1Tx.UserOrigin == true && L1Tx.ToForgeL1TxsNum == nil")
+		}
+		txID[0] = TxIDPrefixL1UserTx
+		var toForgeL1TxsNumBytes [8]byte
+		binary.BigEndian.PutUint64(toForgeL1TxsNumBytes[:], uint64(*l1Tx.ToForgeL1TxsNum))
+		copy(txID[1:9], toForgeL1TxsNumBytes[:])
+	} else {
+		if l1Tx.BatchNum == nil {
+			return nil, fmt.Errorf("L1Tx.UserOrigin == false && L1Tx.BatchNum == nil")
+		}
+		txID[0] = TxIDPrefixL1CoordTx
+		var batchNumBytes [8]byte
+		binary.BigEndian.PutUint64(batchNumBytes[:], uint64(*l1Tx.BatchNum))
+		copy(txID[1:9], batchNumBytes[:])
+	}
 	var positionBytes [2]byte
 	binary.BigEndian.PutUint16(positionBytes[:], uint16(l1Tx.Position))
-	copy(txid[9:11], positionBytes[:])
-	l1Tx.TxID = TxID(txid)
+	copy(txID[9:11], positionBytes[:])
 
-	return l1Tx, nil
+	return &txID, nil
 }
 
 // Tx returns a *Tx from the L1Tx

common/l1tx_test.go

@@ -15,23 +15,40 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func TestNewL1Tx(t *testing.T) {
-	toForge := new(int64)
-	*toForge = 123456
-	fromIdx := new(Idx)
-	*fromIdx = 300
+func TestNewL1UserTx(t *testing.T) {
+	toForge := int64(123456)
+	fromIdx := Idx(300)
 	l1Tx := &L1Tx{
-		ToForgeL1TxsNum: toForge,
+		ToForgeL1TxsNum: &toForge,
 		Position:        71,
+		UserOrigin:      true,
 		ToIdx:           301,
 		TokenID:         5,
 		Amount:          big.NewInt(1),
 		LoadAmount:      big.NewInt(2),
-		FromIdx:         fromIdx,
+		FromIdx:         &fromIdx,
+	}
+	l1Tx, err := NewL1Tx(l1Tx)
+	assert.Nil(t, err)
+	assert.Equal(t, "0x00000000000001e240004700", l1Tx.TxID.String())
+}
+
+func TestNewL1CoordinatorTx(t *testing.T) {
+	fromIdx := Idx(300)
+	batchNum := BatchNum(51966)
+	l1Tx := &L1Tx{
+		Position:   88,
+		UserOrigin: false,
+		ToIdx:      301,
+		TokenID:    5,
+		Amount:     big.NewInt(1),
+		LoadAmount: big.NewInt(2),
+		FromIdx:    &fromIdx,
+		BatchNum:   &batchNum,
 	}
 	l1Tx, err := NewL1Tx(l1Tx)
 	assert.Nil(t, err)
-	assert.Equal(t, "0x01000000000001e240004700", l1Tx.TxID.String())
+	assert.Equal(t, "0x01000000000000cafe005800", l1Tx.TxID.String())
 }
 
 func TestL1TxByteParsers(t *testing.T) {

common/l2tx.go

@@ -111,10 +111,10 @@ func (tx *L2Tx) PoolL2Tx() *PoolL2Tx {
 
 // L2TxsToPoolL2Txs returns an array of []*PoolL2Tx from an array of []*L2Tx,
 // where the PoolL2Tx only have the parameters of a L2Tx filled.
-func L2TxsToPoolL2Txs(txs []*L2Tx) []*PoolL2Tx {
-	var r []*PoolL2Tx
+func L2TxsToPoolL2Txs(txs []*L2Tx) []PoolL2Tx {
+	var r []PoolL2Tx
 	for _, tx := range txs {
-		r = append(r, tx.PoolL2Tx())
+		r = append(r, *tx.PoolL2Tx())
 	}
 	return r
 }

common/pooll2tx.go

@@ -250,15 +250,15 @@ func (tx *PoolL2Tx) Tx() (*Tx, error) {
 	}, nil
 }
 
-// PoolL2TxsToL2Txs returns an array of []*L2Tx from an array of []*PoolL2Tx
-func PoolL2TxsToL2Txs(txs []*PoolL2Tx) ([]*L2Tx, error) {
-	var r []*L2Tx
+// PoolL2TxsToL2Txs returns an array of []L2Tx from an array of []PoolL2Tx
+func PoolL2TxsToL2Txs(txs []PoolL2Tx) ([]L2Tx, error) {
+	var r []L2Tx
 	for _, poolTx := range txs {
 		tx, err := poolTx.L2Tx()
 		if err != nil {
 			return nil, err
 		}
-		r = append(r, tx)
+		r = append(r, *tx)
 	}
 	return r, nil
 }

common/scvars.go

@@ -31,8 +31,8 @@ type AuctionVars struct {
 	AllocationRatio   AllocationRatio
 }
 
-// WithdrawalDelayerVars contains the Withdrawal Delayer smart contract variables
-type WithdrawalDelayerVars struct {
+// WithdrawDelayerVars contains the Withdrawal Delayer smart contract variables
+type WithdrawDelayerVars struct {
 	HermezRollupAddress        eth.Address
 	HermezGovernanceDAOAddress eth.Address
 	WhiteHackGroupAddress      eth.Address

common/tx.go

@@ -12,6 +12,11 @@ import (
 )
 
 const (
+	// TXIDPrefixL1UserTx is the prefix that determines that the TxID is
+	// for a L1UserTx
+	//nolinter:gomnd
+	TxIDPrefixL1UserTx = byte(0)
+
 	// TXIDPrefixL1CoordTx is the prefix that determines that the TxID is
 	// for a L1CoordinatorTx
 	//nolinter:gomnd

coordinator/batch.go

@@ -15,9 +15,9 @@ type BatchInfo struct {
 	serverProof    ServerProofInterface
 	zkInputs       *common.ZKInputs
 	proof          *Proof
-	L1UserTxsExtra []*common.L1Tx
-	L1OperatorTxs  []*common.L1Tx
-	L2Txs          []*common.PoolL2Tx
+	L1UserTxsExtra []common.L1Tx
+	L1OperatorTxs  []common.L1Tx
+	L2Txs          []common.PoolL2Tx
 	// FeesInfo
 	ethTx *types.Transaction
 }
@@ -33,7 +33,7 @@ func NewBatchInfo(batchNum common.BatchNum, serverProof ServerProofInterface) Ba
 
 // SetTxsInfo sets the l1UserTxs, l1OperatorTxs and l2Txs to the BatchInfo data
 // structure
-func (bi *BatchInfo) SetTxsInfo(l1UserTxsExtra, l1OperatorTxs []*common.L1Tx, l2Txs []*common.PoolL2Tx) {
+func (bi *BatchInfo) SetTxsInfo(l1UserTxsExtra, l1OperatorTxs []common.L1Tx, l2Txs []common.PoolL2Tx) {
 	// TBD parameter: feesInfo
 	bi.L1UserTxsExtra = l1UserTxsExtra
 	bi.L1OperatorTxs = l1OperatorTxs

coordinator/coordinator.go

@@ -206,14 +206,14 @@ func (c *Coordinator) forge(serverProof ServerProofInterface) (*BatchInfo, error
 	c.batchNum = c.batchNum + 1
 	batchInfo := NewBatchInfo(c.batchNum, serverProof) // to accumulate metadata of the batch
 
-	var poolL2Txs []*common.PoolL2Tx
+	var poolL2Txs []common.PoolL2Tx
 	// var feesInfo
-	var l1UserTxsExtra, l1OperatorTxs []*common.L1Tx
+	var l1UserTxsExtra, l1OperatorTxs []common.L1Tx
 	// 1. Decide if we forge L2Tx or L1+L2Tx
 	if c.shouldL1L2Batch() {
 		// 2a: L1+L2 txs
 		// l1UserTxs, toForgeL1TxsNumber := c.hdb.GetNextL1UserTxs() // TODO once HistoryDB is ready, uncomment
-		var l1UserTxs []*common.L1Tx = nil                                                                // tmp, depends on HistoryDB
+		var l1UserTxs []common.L1Tx = nil                                                                 // tmp, depends on HistoryDB
 		l1UserTxsExtra, l1OperatorTxs, poolL2Txs, err = c.txsel.GetL1L2TxSelection(c.batchNum, l1UserTxs) // TODO once feesInfo is added to method return, add the var
 		if err != nil {
 			return nil, err
@@ -358,7 +358,7 @@ func (c *Coordinator) purgeRemoveByTimeout() error {
 	return nil // TODO
 }
 
-func (c *Coordinator) purgeInvalidDueToL2TxsSelection(l2Txs []*common.PoolL2Tx) error {
+func (c *Coordinator) purgeInvalidDueToL2TxsSelection(l2Txs []common.PoolL2Tx) error {
 	return nil // TODO
 }
 

db/historydb/historydb.go

@@ -8,6 +8,7 @@ import (
 	ethCommon "github.com/ethereum/go-ethereum/common"
 	"github.com/hermeznetwork/hermez-node/common"
 	"github.com/hermeznetwork/hermez-node/db"
+	"github.com/hermeznetwork/hermez-node/log"
 	"github.com/iden3/go-iden3-crypto/babyjub"
 	"github.com/jmoiron/sqlx"
 
@@ -25,7 +26,7 @@ type HistoryDB struct {
 
 // BlockData contains the information of a Block
 type BlockData struct {
-	block *common.Block
+	Block *common.Block
 	// Rollup
 	// L1UserTxs that were submitted in the block
 	L1UserTxs        []common.L1Tx
@@ -33,10 +34,10 @@ type BlockData struct {
 	RegisteredTokens []common.Token
 	RollupVars       *common.RollupVars
 	// Auction
-	Bids         []common.Bid
-	Coordinators []common.Coordinator
-	AuctionVars  *common.AuctionVars
-	// WithdrawalDelayer
+	Bids                []common.Bid
+	Coordinators        []common.Coordinator
+	AuctionVars         *common.AuctionVars
+	WithdrawDelayerVars *common.WithdrawDelayerVars
 	// TODO: enable when common.WithdrawalDelayerVars is Merged from Synchronizer PR
 	// WithdrawalDelayerVars *common.WithdrawalDelayerVars
 }
@@ -53,6 +54,19 @@ type BatchData struct {
 	Batch            *common.Batch
 }
 
+// NewBatchData creates an empty BatchData with the slices initialized.
+func NewBatchData() *BatchData {
+	return &BatchData{
+		L1Batch:          false,
+		L1UserTxs:        make([]common.L1Tx, 0),
+		L1CoordinatorTxs: make([]common.L1Tx, 0),
+		L2Txs:            make([]common.L2Tx, 0),
+		CreatedAccounts:  make([]common.Account, 0),
+		ExitTree:         make([]common.ExitInfo, 0),
+		Batch:            &common.Batch{},
+	}
+}
+
 // NewHistoryDB initialize the DB
 func NewHistoryDB(db *sqlx.DB) *HistoryDB {
 	return &HistoryDB{db: db}
@@ -536,43 +550,46 @@ func (hdb *HistoryDB) AddBlockSCData(blockData *BlockData) (err error) {
 	}
 	defer func() {
 		if err != nil {
-			err = txn.Rollback()
+			errRollback := txn.Rollback()
+			if errRollback != nil {
+				log.Errorw("Rollback", "err", errRollback)
+			}
 		}
 	}()
 
 	// Add block
-	err = hdb.addBlock(txn, blockData.block)
+	err = hdb.addBlock(txn, blockData.Block)
 	if err != nil {
 		return err
 	}
 
-	// Add l1 Txs
-	if len(blockData.L1UserTxs) > 0 {
-		err = hdb.addL1Txs(txn, blockData.L1UserTxs)
+	// Add Coordinators
+	if len(blockData.Coordinators) > 0 {
+		err = hdb.addCoordinators(txn, blockData.Coordinators)
 		if err != nil {
 			return err
 		}
 	}
 
-	// Add Tokens
-	if len(blockData.RegisteredTokens) > 0 {
-		err = hdb.addTokens(txn, blockData.RegisteredTokens)
+	// Add Bids
+	if len(blockData.Bids) > 0 {
+		err = hdb.addBids(txn, blockData.Bids)
 		if err != nil {
 			return err
 		}
 	}
 
-	// Add Bids
-	if len(blockData.Bids) > 0 {
-		err = hdb.addBids(txn, blockData.Bids)
+	// Add Tokens
+	if len(blockData.RegisteredTokens) > 0 {
+		err = hdb.addTokens(txn, blockData.RegisteredTokens)
 		if err != nil {
 			return err
 		}
 	}
 
-	// Add Coordinators
-	if len(blockData.Coordinators) > 0 {
-		err = hdb.addCoordinators(txn, blockData.Coordinators)
+	// Add l1 Txs
+	if len(blockData.L1UserTxs) > 0 {
+		err = hdb.addL1Txs(txn, blockData.L1UserTxs)
 		if err != nil {
 			return err
 		}

db/l2db/l2db.go

@@ -7,6 +7,7 @@ import (
 
 	ethCommon "github.com/ethereum/go-ethereum/common"
 	"github.com/hermeznetwork/hermez-node/common"
+	"github.com/hermeznetwork/hermez-node/log"
 	"github.com/iden3/go-iden3-crypto/babyjub"
 	"github.com/jmoiron/sqlx"
 
@@ -212,7 +213,10 @@ func (l2db *L2DB) CheckNonces(updatedAccounts []common.Account, batchNum common.
 	defer func() {
 		// Rollback the transaction if there was an error.
 		if err != nil {
-			err = txn.Rollback()
+			errRollback := txn.Rollback()
+			if errRollback != nil {
+				log.Errorw("Rollback", "err", errRollback)
+			}
 		}
 	}()
 	for i := 0; i < len(updatedAccounts); i++ {
@@ -257,7 +261,10 @@ func (l2db *L2DB) Purge(currentBatchNum common.BatchNum) (err error) {
 	defer func() {
 		// Rollback the transaction if there was an error.
 		if err != nil {
-			err = txn.Rollback()
+			errRollback := txn.Rollback()
+			if errRollback != nil {
+				log.Errorw("Rollback", "err", errRollback)
+			}
 		}
 	}()
 	// Delete pending txs that have been in the pool after the TTL if maxTxs is reached

db/statedb/txprocessors.go

@@ -36,7 +36,7 @@ type processedExit struct {
 // type==TypeSynchronizer, assumes that the call is done from the Synchronizer,
 // returns common.ExitTreeLeaf that is later used by the Synchronizer to update
 // the HistoryDB, and adds Nonce & TokenID to the L2Txs.
-func (s *StateDB) ProcessTxs(l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs []*common.PoolL2Tx) (*common.ZKInputs, []common.ExitInfo, error) {
+func (s *StateDB) ProcessTxs(l1usertxs, l1coordinatortxs []common.L1Tx, l2txs []common.PoolL2Tx) (*common.ZKInputs, []common.ExitInfo, error) {
 	var err error
 	var exitTree *merkletree.MerkleTree
 
@@ -69,7 +69,7 @@ func (s *StateDB) ProcessTxs(l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs [
 
 	// assumption: l1usertx are sorted by L1Tx.Position
 	for _, tx := range l1usertxs {
-		exitIdx, exitAccount, newExit, err := s.processL1Tx(exitTree, tx)
+		exitIdx, exitAccount, newExit, err := s.processL1Tx(exitTree, &tx)
 		if err != nil {
 			return nil, nil, err
 		}
@@ -86,7 +86,7 @@ func (s *StateDB) ProcessTxs(l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs [
 		}
 	}
 	for _, tx := range l1coordinatortxs {
-		exitIdx, exitAccount, newExit, err := s.processL1Tx(exitTree, tx)
+		exitIdx, exitAccount, newExit, err := s.processL1Tx(exitTree, &tx)
 		if err != nil {
 			return nil, nil, err
 		}
@@ -106,7 +106,7 @@ func (s *StateDB) ProcessTxs(l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs [
 		}
 	}
 	for _, tx := range l2txs {
-		exitIdx, exitAccount, newExit, err := s.processL2Tx(exitTree, tx)
+		exitIdx, exitAccount, newExit, err := s.processL2Tx(exitTree, &tx)
 		if err != nil {
 			return nil, nil, err
 		}
@@ -194,7 +194,7 @@ func (s *StateDB) ProcessTxs(l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs [
 }
 
 // getTokenIDsBigInt returns the list of TokenIDs in *big.Int format
-func (s *StateDB) getTokenIDsBigInt(l1usertxs, l1coordinatortxs []*common.L1Tx, l2txs []*common.PoolL2Tx) ([]*big.Int, error) {
+func (s *StateDB) getTokenIDsBigInt(l1usertxs, l1coordinatortxs []common.L1Tx, l2txs []common.PoolL2Tx) ([]*big.Int, error) {
 	tokenIDs := make(map[common.TokenID]bool)
 	for i := 0; i < len(l1usertxs); i++ {
 		tokenIDs[l1usertxs[i].TokenID] = true

db/utils.go

@@ -40,7 +40,7 @@ func InitSQLDB(port int, host, user, password, name string) (*sqlx.DB, error) {
 	if err != nil {
 		return nil, err
 	}
-	log.Info("successfully runt ", nMigrations, " migrations")
+	log.Info("successfully ran ", nMigrations, " migrations")
 	return db, nil
 }
 

node/node.go

@@ -1,6 +1,7 @@
 package node
 
 import (
+	"context"
 	"time"
 
 	"github.com/ethereum/go-ethereum/ethclient"
@@ -83,7 +84,10 @@ func NewNode(mode Mode, cfg *config.Node, coordCfg *config.Coordinator) (*Node,
 	}
 	client := eth.NewClient(ethClient, nil, nil, nil)
 
-	sync := synchronizer.NewSynchronizer(client, historyDB, stateDB)
+	sync, err := synchronizer.NewSynchronizer(client, historyDB, stateDB)
+	if err != nil {
+		return nil, err
+	}
 
 	var coord *coordinator.Coordinator
 	if mode == ModeCoordinator {
@@ -223,7 +227,7 @@ func (n *Node) StartSynchronizer() {
 				log.Info("Coordinator stopped")
 				return
 			case <-time.After(n.cfg.Synchronizer.SyncLoopInterval.Duration):
-				if err := n.sync.Sync(); err != nil {
+				if err := n.sync.Sync(context.TODO()); err != nil {
 					log.Errorw("Synchronizer.Sync", "error", err)
 				}
 			}

synchronizer/synchronizer.go

@@ -20,93 +20,102 @@ var (
 
 // rollupData contains information returned by the Rollup SC
 type rollupData struct {
-	l1Txs   []*common.L1Tx
-	batches []*BatchData
+	l1UserTxs []common.L1Tx
+	batches   []historydb.BatchData
 	// withdrawals      []*common.ExitInfo
-	registeredTokens []*common.Token
-	rollupVars       *common.RollupVars
+	registeredTokens []common.Token
+	vars             *common.RollupVars
 }
 
 // NewRollupData creates an empty rollupData with the slices initialized.
 func newRollupData() rollupData {
 	return rollupData{
-		l1Txs:   make([]*common.L1Tx, 0),
-		batches: make([]*BatchData, 0),
+		l1UserTxs: make([]common.L1Tx, 0),
+		batches:   make([]historydb.BatchData, 0),
 		// withdrawals:      make([]*common.ExitInfo, 0),
-		registeredTokens: make([]*common.Token, 0),
+		registeredTokens: make([]common.Token, 0),
 	}
 }
 
 // auctionData contains information returned by the Action SC
 type auctionData struct {
-	bids         []*common.Bid
-	coordinators []*common.Coordinator
-	auctionVars  *common.AuctionVars
+	bids         []common.Bid
+	coordinators []common.Coordinator
+	vars         *common.AuctionVars
 }
 
 // newAuctionData creates an empty auctionData with the slices initialized.
 func newAuctionData() *auctionData {
 	return &auctionData{
-		bids:         make([]*common.Bid, 0),
-		coordinators: make([]*common.Coordinator, 0),
+		bids:         make([]common.Bid, 0),
+		coordinators: make([]common.Coordinator, 0),
 	}
 }
 
-// BatchData contains information about Batches from the contracts
-type BatchData struct {
-	l1UserTxs        []*common.L1Tx
-	l1CoordinatorTxs []*common.L1Tx
-	l2Txs            []*common.L2Tx
-	createdAccounts  []*common.Account
-	exitTree         []common.ExitInfo
-	batch            *common.Batch
+type wdelayerData struct {
+	vars *common.WithdrawDelayerVars
 }
 
+// BatchData contains information about Batches from the contracts
+// type BatchData struct {
+// 	l1UserTxs        []*common.L1Tx
+// 	l1CoordinatorTxs []*common.L1Tx
+// 	l2Txs            []*common.L2Tx
+// 	createdAccounts  []*common.Account
+// 	exitTree         []*common.ExitInfo
+// 	batch            *common.Batch
+// }
+
 // NewBatchData creates an empty BatchData with the slices initialized.
-func NewBatchData() *BatchData {
-	return &BatchData{
-		l1UserTxs:        make([]*common.L1Tx, 0),
-		l1CoordinatorTxs: make([]*common.L1Tx, 0),
-		l2Txs:            make([]*common.L2Tx, 0),
-		createdAccounts:  make([]*common.Account, 0),
-		exitTree:         make([]common.ExitInfo, 0),
-	}
-}
+// func NewBatchData() *BatchData {
+// 	return &BatchData{
+// 		l1UserTxs:        make([]*common.L1Tx, 0),
+// 		l1CoordinatorTxs: make([]*common.L1Tx, 0),
+// 		l2Txs:            make([]*common.L2Tx, 0),
+// 		createdAccounts:  make([]*common.Account, 0),
+// 		exitTree:         make([]*common.ExitInfo, 0),
+// 	}
+// }
 
 // BlockData contains information about Blocks from the contracts
-type BlockData struct {
-	block *common.Block
-	// Rollup
-	l1Txs   []*common.L1Tx // TODO: Answer: User? Coordinator? Both?
-	batches []*BatchData   // TODO: Also contains L1Txs!
-	// withdrawals      []*common.ExitInfo // TODO
-	registeredTokens []*common.Token
-	rollupVars       *common.RollupVars
-	// Auction
-	bids         []*common.Bid
-	coordinators []*common.Coordinator
-	auctionVars  *common.AuctionVars
-	// WithdrawalDelayer
-	withdrawalDelayerVars *common.WithdrawalDelayerVars
-}
+// type blockData struct {
+// 	Block *common.Block
+// 	// Rollup
+// 	L1Txs   []*common.L1Tx // TODO: Answer: User? Coordinator? Both?
+// 	Batches []*BatchData   // TODO: Also contains L1Txs!
+// 	// withdrawals      []*common.ExitInfo // TODO
+// 	RegisteredTokens []common.Token
+// 	RollupVars       *common.RollupVars
+// 	// Auction
+// 	Bids         []*common.Bid
+// 	Coordinators []*common.Coordinator
+// 	AuctionVars  *common.AuctionVars
+// 	// WithdrawalDelayer
+// 	WithdrawalDelayerVars *common.WithdrawalDelayerVars
+// }
 
 // Synchronizer implements the Synchronizer type
 type Synchronizer struct {
-	ethClient       *eth.Client
-	historyDB       *historydb.HistoryDB
-	stateDB         *statedb.StateDB
-	firstSavedBlock *common.Block
-	mux             sync.Mutex
+	ethClient        eth.ClientInterface
+	auctionConstants eth.AuctionConstants
+	historyDB        *historydb.HistoryDB
+	stateDB          *statedb.StateDB
+	firstSavedBlock  *common.Block
+	mux              sync.Mutex
 }
 
 // NewSynchronizer creates a new Synchronizer
-func NewSynchronizer(ethClient *eth.Client, historyDB *historydb.HistoryDB, stateDB *statedb.StateDB) *Synchronizer {
-	s := &Synchronizer{
-		ethClient: ethClient,
-		historyDB: historyDB,
-		stateDB:   stateDB,
+func NewSynchronizer(ethClient eth.ClientInterface, historyDB *historydb.HistoryDB, stateDB *statedb.StateDB) (*Synchronizer, error) {
+	auctionConstants, err := ethClient.AuctionConstants()
+	if err != nil {
+		return nil, err
 	}
-	return s
+	return &Synchronizer{
+		ethClient:        ethClient,
+		auctionConstants: *auctionConstants,
+		historyDB:        historyDB,
+		stateDB:          stateDB,
+	}, nil
 }
 
 // TODO: Be smart about locking: only lock during the read/write operations
@@ -116,7 +125,7 @@ func NewSynchronizer(ethClient *eth.Client, historyDB *historydb.HistoryDB, stat
 // TODO: Add argument: maximum number of blocks to process
 // TODO: Check reorgs in the middle of syncing a block.  Probably make
 // rollupSync, auctionSync and withdrawalSync return the block hash.
-func (s *Synchronizer) Sync() error {
+func (s *Synchronizer) Sync(ctx context.Context) error {
 	// Avoid new sync while performing one
 	s.mux.Lock()
 	defer s.mux.Unlock()
@@ -130,11 +139,10 @@ func (s *Synchronizer) Sync() error {
 	}
 	// If we don't have any stored block, we must do a full sync starting from the rollup genesis block
 	if err == sql.ErrNoRows {
-		// TODO: Query rollup constants and genesis information, store them
-		nextBlockNum = 1234 // TODO: Replace this with genesisBlockNum
+		nextBlockNum = s.auctionConstants.GenesisBlockNum
 	} else {
 		// Get the latest block we have in History DB from blockchain to detect a reorg
-		ethBlock, err := s.ethClient.EthBlockByNumber(context.Background(), lastSavedBlock.EthBlockNum)
+		ethBlock, err := s.ethClient.EthBlockByNumber(ctx, lastSavedBlock.EthBlockNum)
 		if err != nil {
 			return err
 		}
@@ -165,7 +173,7 @@ func (s *Synchronizer) Sync() error {
 
 	log.Debugf("Blocks to sync: %v (firstBlockToSync: %v, latestBlock: %v)", latestBlockNum-nextBlockNum+1, nextBlockNum, latestBlockNum)
 
-	for nextBlockNum < latestBlockNum {
+	for nextBlockNum <= latestBlockNum {
 		ethBlock, err := s.ethClient.EthBlockByNumber(context.Background(), nextBlockNum)
 		if err != nil {
 			return err
@@ -195,34 +203,40 @@ func (s *Synchronizer) Sync() error {
 		}
 
 		// Group all the block data into the structs to save into HistoryDB
-		var blockData BlockData
+		var blockData historydb.BlockData
 
-		blockData.block = ethBlock
+		blockData.Block = ethBlock
 
 		if rollupData != nil {
-			blockData.l1Txs = rollupData.l1Txs
-			blockData.batches = rollupData.batches
+			blockData.L1UserTxs = rollupData.l1UserTxs
+			blockData.Batches = rollupData.batches
 			// blockData.withdrawals = rollupData.withdrawals // TODO
-			blockData.registeredTokens = rollupData.registeredTokens
-			blockData.rollupVars = rollupData.rollupVars
+			blockData.RegisteredTokens = rollupData.registeredTokens
+			blockData.RollupVars = rollupData.vars
 		}
 
 		if auctionData != nil {
-			blockData.bids = auctionData.bids
-			blockData.coordinators = auctionData.coordinators
-			blockData.auctionVars = auctionData.auctionVars
+			blockData.Bids = auctionData.bids
+			blockData.Coordinators = auctionData.coordinators
+			blockData.AuctionVars = auctionData.vars
 		}
 
 		if wdelayerData != nil {
-			blockData.withdrawalDelayerVars = wdelayerData
+			blockData.WithdrawDelayerVars = wdelayerData.vars
 		}
 
 		// Add rollupData and auctionData once the method is updated
 		// TODO: Save Whole Struct -> AddBlockSCData(blockData)
-		err = s.historyDB.AddBlock(blockData.block)
+		log.Debugw("Sync()", "block", blockData)
+		// err = s.historyDB.AddBlock(blockData.Block)
+		// if err != nil {
+		// 	return err
+		// }
+		err = s.historyDB.AddBlockSCData(&blockData)
 		if err != nil {
 			return err
 		}
+		nextBlockNum++
 	}
 
 	return nil
@@ -358,18 +372,18 @@ func (s *Synchronizer) rollupSync(blockNum int64) (*rollupData, error) {
 	// }
 
 	// Get L1UserTX
-	rollupData.l1Txs, err = getL1UserTx(rollupEvents.L1UserTx, blockNum)
+	rollupData.l1UserTxs, err = getL1UserTx(rollupEvents.L1UserTx, blockNum)
 	if err != nil {
 		return nil, err
 	}
 
 	// Get ForgeBatch events to get the L1CoordinatorTxs
-	for _, fbEvent := range rollupEvents.ForgeBatch {
-		batchData := NewBatchData()
+	for _, evtForgeBatch := range rollupEvents.ForgeBatch {
+		batchData := historydb.NewBatchData()
 		position := 0
 
 		// Get the input for each Tx
-		forgeBatchArgs, err := s.ethClient.RollupForgeBatchArgs(fbEvent.EthTxHash)
+		forgeBatchArgs, err := s.ethClient.RollupForgeBatchArgs(evtForgeBatch.EthTxHash)
 		if err != nil {
 			return nil, err
 		}
@@ -399,14 +413,14 @@ func (s *Synchronizer) rollupSync(blockNum int64) (*rollupData, error) {
 				l1CoordinatorTx.UserOrigin = false
 				l1CoordinatorTx.EthBlockNum = blockNum
 				bn := new(common.BatchNum)
-				*bn = common.BatchNum(fbEvent.BatchNum)
+				*bn = common.BatchNum(evtForgeBatch.BatchNum)
 				l1CoordinatorTx.BatchNum = bn
-				l1CoordinatorTx, err = common.NewL1Tx(l1CoordinatorTx)
+				l1Tx, err := common.NewL1Tx(l1CoordinatorTx)
 				if err != nil {
 					return nil, err
 				}
 
-				batchData.l1CoordinatorTxs = append(batchData.l1CoordinatorTxs, l1CoordinatorTx)
+				batchData.L1CoordinatorTxs = append(batchData.L1CoordinatorTxs, *l1Tx)
 
 				// Check if we have to register an account
 				// if l1CoordinatorTx.FromIdx == 0 {
@@ -435,7 +449,7 @@ func (s *Synchronizer) rollupSync(blockNum int64) (*rollupData, error) {
 		// TODO: Get createdAccounts from ProcessTxs()
 		// TODO: Get CollectedFees from ProcessTxs()
 		// TODO: Pass forgeBatchArgs.FeeIdxCoordinator to ProcessTxs()
-		_, exitInfo, err := s.stateDB.ProcessTxs(batchData.l1UserTxs, batchData.l1CoordinatorTxs, poolL2Txs)
+		_, exitInfo, err := s.stateDB.ProcessTxs(batchData.L1UserTxs, batchData.L1CoordinatorTxs, poolL2Txs)
 		if err != nil {
 			return nil, err
 		}
@@ -444,13 +458,13 @@ func (s *Synchronizer) rollupSync(blockNum int64) (*rollupData, error) {
 		if err != nil {
 			return nil, err
 		}
-		batchData.l2Txs = append(batchData.l2Txs, l2Txs...)
+		batchData.L2Txs = append(batchData.L2Txs, l2Txs...)
 
-		batchData.exitTree = exitInfo
+		batchData.ExitTree = exitInfo
 
 		// Get Batch information
 		batch := &common.Batch{
-			BatchNum:    common.BatchNum(fbEvent.BatchNum),
+			BatchNum:    common.BatchNum(evtForgeBatch.BatchNum),
 			EthBlockNum: blockNum,
 			// ForgerAddr: , TODO: Get it from ethClient -> Add ForgerAddr to RollupEventForgeBatch
 			// CollectedFees: , TODO: Clarify where to get them if they are still needed
@@ -460,19 +474,23 @@ func (s *Synchronizer) rollupSync(blockNum int64) (*rollupData, error) {
 			ForgeL1TxsNum: &forgeL1TxsNum,
 			// SlotNum: TODO: Calculate once ethClient provides the info // calculate from blockNum + ethClient Constants
 		}
-		batchData.batch = batch
-		rollupData.batches = append(rollupData.batches, batchData)
+		batchData.Batch = batch
+		rollupData.batches = append(rollupData.batches, *batchData)
 	}
 
 	// Get Registered Tokens
-	for _, eAddToken := range rollupEvents.AddToken {
-		var token *common.Token
+	for _, evtAddToken := range rollupEvents.AddToken {
+		var token common.Token
 
-		token.TokenID = common.TokenID(eAddToken.TokenID)
-		token.EthAddr = eAddToken.Address
+		token.TokenID = common.TokenID(evtAddToken.TokenID)
+		token.EthAddr = evtAddToken.Address
 		token.EthBlockNum = blockNum
 
 		// TODO: Add external information consulting SC about it using Address
+		token.Name = "TODO"
+		token.Symbol = "TODO"
+		token.Decimals = 8 // TODO
+
 		rollupData.registeredTokens = append(rollupData.registeredTokens, token)
 	}
 
@@ -498,22 +516,22 @@ func (s *Synchronizer) auctionSync(blockNum int64) (*auctionData, error) {
 	}
 
 	// Get bids
-	for _, eNewBid := range auctionEvents.NewBid {
-		bid := &common.Bid{
-			SlotNum:     common.SlotNum(eNewBid.Slot),
-			BidValue:    eNewBid.BidAmount,
-			Bidder:      eNewBid.Bidder,
+	for _, evtNewBid := range auctionEvents.NewBid {
+		bid := common.Bid{
+			SlotNum:     common.SlotNum(evtNewBid.Slot),
+			BidValue:    evtNewBid.BidAmount,
+			Bidder:      evtNewBid.Bidder,
 			EthBlockNum: blockNum,
 		}
 		auctionData.bids = append(auctionData.bids, bid)
 	}
 
 	// Get Coordinators
-	for _, eNewCoordinator := range auctionEvents.SetCoordinator {
-		coordinator := &common.Coordinator{
-			Bidder: eNewCoordinator.BidderAddress,
-			Forger: eNewCoordinator.ForgerAddress,
-			URL:    eNewCoordinator.CoordinatorURL,
+	for _, evtSetCoordinator := range auctionEvents.SetCoordinator {
+		coordinator := common.Coordinator{
+			Bidder: evtSetCoordinator.BidderAddress,
+			Forger: evtSetCoordinator.ForgerAddress,
+			URL:    evtSetCoordinator.CoordinatorURL,
 		}
 		auctionData.coordinators = append(auctionData.coordinators, coordinator)
 	}
@@ -537,7 +555,7 @@ func (s *Synchronizer) auctionSync(blockNum int64) (*auctionData, error) {
 }
 
 // wdelayerSync gets information from the Withdrawal Delayer Contract
-func (s *Synchronizer) wdelayerSync(blockNum int64) (*common.WithdrawalDelayerVars, error) {
+func (s *Synchronizer) wdelayerSync(blockNum int64) (*wdelayerData, error) {
 	// TODO: VARS
 	// TODO: CONSTANTS
 
@@ -559,24 +577,23 @@ func (s *Synchronizer) wdelayerSync(blockNum int64) (*common.WithdrawalDelayerVa
 // 	return forgeBatchArgs.NewLastIdx + 1, nil
 // }
 
-func getL1UserTx(l1UserTxEvents []eth.RollupEventL1UserTx, blockNum int64) ([]*common.L1Tx, error) {
-	l1Txs := make([]*common.L1Tx, 0)
+func getL1UserTx(eventsL1UserTx []eth.RollupEventL1UserTx, blockNum int64) ([]common.L1Tx, error) {
+	l1Txs := make([]common.L1Tx, 0)
 
-	for _, eL1UserTx := range l1UserTxEvents {
+	for _, evtL1UserTx := range eventsL1UserTx {
 		// Fill aditional Tx fields
-		toForge := new(int64)
-		*toForge = eL1UserTx.ToForgeL1TxsNum
-		eL1UserTx.L1Tx.ToForgeL1TxsNum = toForge
-		eL1UserTx.L1Tx.Position = eL1UserTx.Position
-		eL1UserTx.L1Tx.UserOrigin = true
-		eL1UserTx.L1Tx.EthBlockNum = blockNum
-		nL1Tx, err := common.NewL1Tx(&eL1UserTx.L1Tx)
+		toForge := evtL1UserTx.ToForgeL1TxsNum
+		evtL1UserTx.L1Tx.ToForgeL1TxsNum = &toForge
+		evtL1UserTx.L1Tx.Position = evtL1UserTx.Position
+		evtL1UserTx.L1Tx.UserOrigin = true
+		evtL1UserTx.L1Tx.EthBlockNum = blockNum
+		nL1Tx, err := common.NewL1Tx(&evtL1UserTx.L1Tx)
 		if err != nil {
 			return nil, err
 		}
-		eL1UserTx.L1Tx = *nL1Tx
+		evtL1UserTx.L1Tx = *nL1Tx
 
-		l1Txs = append(l1Txs, &eL1UserTx.L1Tx)
+		l1Txs = append(l1Txs, evtL1UserTx.L1Tx)
 	}
 	return l1Txs, nil
 }

synchronizer/synchronizer_test.go

@@ -1,25 +1,37 @@
 package synchronizer
 
 import (
+	"context"
 	"io/ioutil"
+	"math/big"
 	"os"
 	"testing"
 
-	"github.com/ethereum/go-ethereum/ethclient"
+	ethCommon "github.com/ethereum/go-ethereum/common"
 	dbUtils "github.com/hermeznetwork/hermez-node/db"
 	"github.com/hermeznetwork/hermez-node/db/historydb"
 	"github.com/hermeznetwork/hermez-node/db/statedb"
-	"github.com/hermeznetwork/hermez-node/eth"
+	"github.com/hermeznetwork/hermez-node/test"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
-func Test(t *testing.T) {
+type timer struct {
+	time int64
+}
+
+func (t *timer) Time() int64 {
+	currentTime := t.time
+	t.time++
+	return currentTime
+}
+
+func TestSync(t *testing.T) {
 	// Int State DB
 	dir, err := ioutil.TempDir("", "tmpdb")
 	require.Nil(t, err)
 
-	sdb, err := statedb.NewStateDB(dir, statedb.TypeSynchronizer, 32)
+	stateDB, err := statedb.NewStateDB(dir, statedb.TypeSynchronizer, 32)
 	assert.Nil(t, err)
 
 	// Init History DB
@@ -27,23 +39,56 @@ func Test(t *testing.T) {
 	db, err := dbUtils.InitSQLDB(5432, "localhost", "hermez", pass, "hermez")
 	require.Nil(t, err)
 	historyDB := historydb.NewHistoryDB(db)
-	err = historyDB.Reorg(0)
+	// Clear DB
+	err = historyDB.Reorg(-1)
 	assert.Nil(t, err)
 
 	// Init eth client
-	ehtClientDialURL := os.Getenv("ETHCLIENT_DIAL_URL")
-	ethClient, err := ethclient.Dial(ehtClientDialURL)
+	var timer timer
+	clientSetup := test.NewClientSetupExample()
+	client := test.NewClient(true, &timer, &ethCommon.Address{}, clientSetup)
+
+	// Create Synchronizer
+	s, err := NewSynchronizer(client, historyDB, stateDB)
 	require.Nil(t, err)
 
-	client := eth.NewClient(ethClient, nil, nil, nil)
+	// Test Sync for ethereum genesis block
+	err = s.Sync(context.Background())
+	require.Nil(t, err)
 
-	// Create Synchronizer
-	s := NewSynchronizer(client, historyDB, sdb)
-	require.NotNil(t, s)
+	blocks, err := s.historyDB.GetBlocks(0, 9999)
+	require.Nil(t, err)
+	assert.Equal(t, int64(0), blocks[0].EthBlockNum)
+
+	// Test Sync for a block with new Tokens and L1UserTxs
+	// accounts := test.GenerateKeys(t, []string{"A", "B", "C", "D"})
+	l1UserTxs, _, _, _ := test.GenerateTestTxsFromSet(t, `
+A (1): 10
+A (2): 20
+B (1): 5
+C (1): 8
+D (3): 15
+> advance batch
+	`)
+	require.Greater(t, len(l1UserTxs[0]), 0)
+	// require.Greater(t, len(tokens), 0)
+
+	for i := 1; i <= 3; i++ {
+		_, err := client.RollupAddToken(ethCommon.BigToAddress(big.NewInt(int64(i * 10000))))
+		require.Nil(t, err)
+	}
 
-	// Test Sync
-	// err = s.Sync()
-	// require.Nil(t, err)
+	for _, l1UserTx := range l1UserTxs[0] {
+		client.CtlAddL1TxUser(&l1UserTx)
+	}
+	client.CtlMineBlock()
+
+	err = s.Sync(context.Background())
+	require.Nil(t, err)
+
+	getTokens, err := s.historyDB.GetTokens()
+	require.Nil(t, err)
+	assert.Equal(t, 3, len(getTokens))
 
 	// TODO: Reorg will be properly tested once we have the mock ethClient implemented
 	/*

test/ethclient.go

@@ -329,10 +329,11 @@ func NewClient(l bool, timer Timer, addr *ethCommon.Address, setup *ClientSetup)
 	blockCurrent := Block{
 		Rollup: &RollupBlock{
 			State: eth.RollupState{
-				StateRoot:              big.NewInt(0),
-				ExitRoots:              make([]*big.Int, 0),
-				ExitNullifierMap:       make(map[[256 / 8]byte]bool),
-				TokenList:              make([]ethCommon.Address, 0),
+				StateRoot:        big.NewInt(0),
+				ExitRoots:        make([]*big.Int, 0),
+				ExitNullifierMap: make(map[[256 / 8]byte]bool),
+				// TokenID = 0 is ETH.  Set first entry in TokenList with 0x0 address for ETH.
+				TokenList:              []ethCommon.Address{ethCommon.Address{}},
 				TokenMap:               make(map[ethCommon.Address]bool),
 				MapL1TxQueue:           mapL1TxQueue,
 				LastL1L2Batch:          0,
@@ -597,7 +598,11 @@ func (c *Client) CtlAddL1TxUser(l1Tx *common.L1Tx) {
 		panic("l1Tx.TokenID + 1 > len(r.State.TokenList)")
 	}
 	queue.L1TxQueue = append(queue.L1TxQueue, *l1Tx)
-	r.Events.L1UserTx = append(r.Events.L1UserTx, eth.RollupEventL1UserTx{L1Tx: *l1Tx})
+	r.Events.L1UserTx = append(r.Events.L1UserTx, eth.RollupEventL1UserTx{
+		L1Tx:            *l1Tx,
+		ToForgeL1TxsNum: r.State.LastToForgeL1TxsNum,
+		Position:        len(queue.L1TxQueue) - 1,
+	})
 }
 
 type transactionData struct {

test/historydb.go

@@ -152,6 +152,12 @@ func GenL1Txs(
 			LoadAmountUSD: lUSD,
 			EthBlockNum:   blocks[i%len(blocks)].EthBlockNum,
 		}
+		if tx.UserOrigin {
+			n := nextTxsNum
+			tx.ToForgeL1TxsNum = &n
+		} else {
+			tx.BatchNum = &batches[i%len(batches)].BatchNum
+		}
 		nTx, err := common.NewL1Tx(&tx)
 		if err != nil {
 			panic(err)
@@ -163,7 +169,8 @@ func GenL1Txs(
 			setFromToAndAppend(fromIdx, tx, i, nUserTxs, userAddr, accounts, &userTxs, &othersTxs)
 		} else {
 			// Add unforged txs
-			tx.ToForgeL1TxsNum = nextTxsNum
+			n := nextTxsNum
+			tx.ToForgeL1TxsNum = &n
 			tx.UserOrigin = true
 			setFromToAndAppend(fromIdx, tx, i, nUserTxs, userAddr, accounts, &userTxs, &othersTxs)
 		}
@@ -172,13 +179,13 @@ func GenL1Txs(
 }
 
 // GetNextToForgeNumAndBatch returns the next BatchNum and ForgeL1TxsNum to be added
-func GetNextToForgeNumAndBatch(batches []common.Batch) (common.BatchNum, *int64) {
+func GetNextToForgeNumAndBatch(batches []common.Batch) (common.BatchNum, int64) {
 	batchNum := batches[len(batches)-1].BatchNum + 1
-	toForgeL1TxsNum := new(int64)
+	var toForgeL1TxsNum int64
 	found := false
 	for i := len(batches) - 1; i >= 0; i-- {
 		if batches[i].ForgeL1TxsNum != nil {
-			*toForgeL1TxsNum = *batches[i].ForgeL1TxsNum + 1
+			toForgeL1TxsNum = *batches[i].ForgeL1TxsNum + 1
 			found = true
 			break
 		}

test/txs.go

@@ -52,16 +52,16 @@ func GenerateKeys(t *testing.T, accNames []string) map[string]*Account {
 
 // GenerateTestTxs generates L1Tx & PoolL2Tx in a deterministic way for the
 // given Instructions.
-func GenerateTestTxs(t *testing.T, instructions Instructions) ([][]*common.L1Tx, [][]*common.L1Tx, [][]*common.PoolL2Tx, []common.Token) {
+func GenerateTestTxs(t *testing.T, instructions Instructions) ([][]common.L1Tx, [][]common.L1Tx, [][]common.PoolL2Tx, []common.Token) {
 	accounts := GenerateKeys(t, instructions.Accounts)
 	l1CreatedAccounts := make(map[string]*Account)
 
-	var batchL1Txs []*common.L1Tx
-	var batchCoordinatorL1Txs []*common.L1Tx
-	var batchPoolL2Txs []*common.PoolL2Tx
-	var l1Txs [][]*common.L1Tx
-	var coordinatorL1Txs [][]*common.L1Tx
-	var poolL2Txs [][]*common.PoolL2Tx
+	var batchL1Txs []common.L1Tx
+	var batchCoordinatorL1Txs []common.L1Tx
+	var batchPoolL2Txs []common.PoolL2Tx
+	var l1Txs [][]common.L1Tx
+	var coordinatorL1Txs [][]common.L1Tx
+	var poolL2Txs [][]common.PoolL2Tx
 	idx := 256
 	for _, inst := range instructions.Instructions {
 		switch inst.Type {
@@ -71,10 +71,11 @@ func GenerateTestTxs(t *testing.T, instructions Instructions) ([][]*common.L1Tx,
 				FromEthAddr: accounts[idxTokenIDToString(inst.From, inst.TokenID)].Addr,
 				FromBJJ:     accounts[idxTokenIDToString(inst.From, inst.TokenID)].BJJ.Public(),
 				TokenID:     inst.TokenID,
+				Amount:      big.NewInt(0),
 				LoadAmount:  big.NewInt(int64(inst.Amount)),
 				Type:        common.TxTypeCreateAccountDeposit,
 			}
-			batchL1Txs = append(batchL1Txs, &tx)
+			batchL1Txs = append(batchL1Txs, tx)
 			if accounts[idxTokenIDToString(inst.From, inst.TokenID)].Idx == common.Idx(0) { // if account.Idx is not set yet, set it and increment idx
 				accounts[idxTokenIDToString(inst.From, inst.TokenID)].Idx = common.Idx(idx)
 
@@ -93,7 +94,7 @@ func GenerateTestTxs(t *testing.T, instructions Instructions) ([][]*common.L1Tx,
 				}
 				accounts[idxTokenIDToString(inst.To, inst.TokenID)].Idx = common.Idx(idx)
 				l1CreatedAccounts[idxTokenIDToString(inst.To, inst.TokenID)] = accounts[idxTokenIDToString(inst.To, inst.TokenID)]
-				batchCoordinatorL1Txs = append(batchCoordinatorL1Txs, &tx)
+				batchCoordinatorL1Txs = append(batchCoordinatorL1Txs, tx)
 				idx++
 			}
 			toIdx := new(common.Idx)
@@ -132,7 +133,7 @@ func GenerateTestTxs(t *testing.T, instructions Instructions) ([][]*common.L1Tx,
 			tx.Signature = sig
 
 			accounts[idxTokenIDToString(inst.From, inst.TokenID)].Nonce++
-			batchPoolL2Txs = append(batchPoolL2Txs, &tx)
+			batchPoolL2Txs = append(batchPoolL2Txs, tx)
 
 		case common.TxTypeExit, common.TxTypeForceExit:
 			fromIdx := new(common.Idx)
@@ -144,14 +145,14 @@ func GenerateTestTxs(t *testing.T, instructions Instructions) ([][]*common.L1Tx,
 				Amount:  big.NewInt(int64(inst.Amount)),
 				Type:    common.TxTypeExit,
 			}
-			batchL1Txs = append(batchL1Txs, &tx)
+			batchL1Txs = append(batchL1Txs, tx)
 		case TypeNewBatch:
 			l1Txs = append(l1Txs, batchL1Txs)
 			coordinatorL1Txs = append(coordinatorL1Txs, batchCoordinatorL1Txs)
 			poolL2Txs = append(poolL2Txs, batchPoolL2Txs)
-			batchL1Txs = []*common.L1Tx{}
-			batchCoordinatorL1Txs = []*common.L1Tx{}
-			batchPoolL2Txs = []*common.PoolL2Tx{}
+			batchL1Txs = []common.L1Tx{}
+			batchCoordinatorL1Txs = []common.L1Tx{}
+			batchPoolL2Txs = []common.PoolL2Tx{}
 		default:
 			continue
 		}
@@ -184,7 +185,7 @@ func GenerateTestTxs(t *testing.T, instructions Instructions) ([][]*common.L1Tx,
 
 // GenerateTestTxsFromSet reurns the L1 & L2 transactions for a given Set of
 // Instructions code
-func GenerateTestTxsFromSet(t *testing.T, set string) ([][]*common.L1Tx, [][]*common.L1Tx, [][]*common.PoolL2Tx, []common.Token) {
+func GenerateTestTxsFromSet(t *testing.T, set string) ([][]common.L1Tx, [][]common.L1Tx, [][]common.PoolL2Tx, []common.Token) {
 	parser := NewParser(strings.NewReader(set))
 	instructions, err := parser.Parse()
 	require.Nil(t, err)

txselector/txselector.go

@@ -16,7 +16,7 @@ import (
 )
 
 // txs implements the interface Sort for an array of Tx
-type txs []*common.PoolL2Tx
+type txs []common.PoolL2Tx
 
 func (t txs) Len() int {
 	return len(t)
@@ -68,7 +68,7 @@ func (txsel *TxSelector) Reset(batchNum common.BatchNum) error {
 }
 
 // GetL2TxSelection returns a selection of the L2Txs for the next batch, from the L2DB pool
-func (txsel *TxSelector) GetL2TxSelection(batchNum common.BatchNum) ([]*common.PoolL2Tx, error) {
+func (txsel *TxSelector) GetL2TxSelection(batchNum common.BatchNum) ([]common.PoolL2Tx, error) {
 	// get pending l2-tx from tx-pool
 	l2TxsRaw, err := txsel.l2db.GetPendingTxs() // once l2db ready, maybe use parameter 'batchNum'
 	if err != nil {
@@ -81,7 +81,7 @@ func (txsel *TxSelector) GetL2TxSelection(batchNum common.BatchNum) ([]*common.P
 		_, err = txsel.localAccountsDB.GetAccount(&tx.FromIdx)
 		if err == nil {
 			// if FromIdx has an account into the AccountsDB
-			validTxs = append(validTxs, tx)
+			validTxs = append(validTxs, *tx)
 		}
 	}
 
@@ -98,7 +98,7 @@ func (txsel *TxSelector) GetL2TxSelection(batchNum common.BatchNum) ([]*common.P
 }
 
 // GetL1L2TxSelection returns the selection of L1 + L2 txs
-func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*common.L1Tx) ([]*common.L1Tx, []*common.L1Tx, []*common.PoolL2Tx, error) {
+func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []common.L1Tx) ([]common.L1Tx, []common.L1Tx, []common.PoolL2Tx, error) {
 	// apply l1-user-tx to localAccountDB
 	//     create new leaves
 	//     update balances
@@ -111,7 +111,7 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 	}
 
 	var validTxs txs
-	var l1CoordinatorTxs []*common.L1Tx
+	var l1CoordinatorTxs []common.L1Tx
 	positionL1 := len(l1Txs)
 
 	// if tx.ToIdx>=256, tx.ToIdx should exist to localAccountsDB, if so,
@@ -127,7 +127,7 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 				// a L1CoordinatorTx of this type, in the DB there still seem
 				// that needs to create a new L1CoordinatorTx, but as is already
 				// created, the tx is valid
-				validTxs = append(validTxs, l2TxsRaw[i])
+				validTxs = append(validTxs, *l2TxsRaw[i])
 				continue
 			}
 
@@ -143,7 +143,7 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 						// account for ToEthAddr&ToBJJ already exist,
 						// there is no need to create a new one.
 						// tx valid, StateDB will use the ToIdx==0 to define the AuxToIdx
-						validTxs = append(validTxs, l2TxsRaw[i])
+						validTxs = append(validTxs, *l2TxsRaw[i])
 						continue
 					}
 					// if not, check if AccountCreationAuth exist for that ToEthAddr&BJJ
@@ -159,7 +159,7 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 						log.Debugw("invalid L2Tx: ToIdx not found in StateDB, neither ToEthAddr & ToBJJ found in AccountCreationAuths L2DB", "ToIdx", l2TxsRaw[i].ToIdx, "ToEthAddr", l2TxsRaw[i].ToEthAddr, "ToBJJ", l2TxsRaw[i].ToBJJ)
 						continue
 					}
-					validTxs = append(validTxs, l2TxsRaw[i])
+					validTxs = append(validTxs, *l2TxsRaw[i])
 				} else {
 					// case: ToBJJ==0:
 					// if idx exist for EthAddr use it
@@ -168,7 +168,7 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 						// account for ToEthAddr already exist,
 						// there is no need to create a new one.
 						// tx valid, StateDB will use the ToIdx==0 to define the AuxToIdx
-						validTxs = append(validTxs, l2TxsRaw[i])
+						validTxs = append(validTxs, *l2TxsRaw[i])
 						continue
 					}
 					// if not, check if AccountCreationAuth exist for that ToEthAddr
@@ -178,10 +178,10 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 						log.Debugw("invalid L2Tx: ToIdx not found in StateDB, neither ToEthAddr found in AccountCreationAuths L2DB", "ToIdx", l2TxsRaw[i].ToIdx, "ToEthAddr", l2TxsRaw[i].ToEthAddr)
 						continue
 					}
-					validTxs = append(validTxs, l2TxsRaw[i])
+					validTxs = append(validTxs, *l2TxsRaw[i])
 				}
 				// create L1CoordinatorTx for the accountCreation
-				l1CoordinatorTx := &common.L1Tx{
+				l1CoordinatorTx := common.L1Tx{
 					Position:    positionL1,
 					UserOrigin:  false,
 					FromEthAddr: accAuth.EthAddr,
@@ -199,7 +199,7 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 					// account for ToEthAddr&ToBJJ already exist, (where ToEthAddr==0xff)
 					// there is no need to create a new one.
 					// tx valid, StateDB will use the ToIdx==0 to define the AuxToIdx
-					validTxs = append(validTxs, l2TxsRaw[i])
+					validTxs = append(validTxs, *l2TxsRaw[i])
 					continue
 				}
 				// if idx don't exist for EthAddr&BJJ,
@@ -210,7 +210,7 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 					log.Warn("l2TxsRaw[i].ToEthAddr should not be nil")
 					continue
 				}
-				l1CoordinatorTx := &common.L1Tx{
+				l1CoordinatorTx := common.L1Tx{
 					Position:    positionL1,
 					UserOrigin:  false,
 					FromEthAddr: *l2TxsRaw[i].ToEthAddr,
@@ -230,10 +230,10 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 				continue
 			}
 			// Account found in the DB, include the l2Tx in the selection
-			validTxs = append(validTxs, l2TxsRaw[i])
+			validTxs = append(validTxs, *l2TxsRaw[i])
 		} else if *l2TxsRaw[i].ToIdx == common.Idx(1) { // nil already checked before
 			// valid txs (of Exit type)
-			validTxs = append(validTxs, l2TxsRaw[i])
+			validTxs = append(validTxs, *l2TxsRaw[i])
 		}
 	}
 
@@ -254,7 +254,7 @@ func (txsel *TxSelector) GetL1L2TxSelection(batchNum common.BatchNum, l1Txs []*c
 	return l1Txs, l1CoordinatorTxs, l2Txs, nil
 }
 
-func checkAlreadyPendingToCreate(l1CoordinatorTxs []*common.L1Tx, addr *ethCommon.Address, bjj *babyjub.PublicKey) bool {
+func checkAlreadyPendingToCreate(l1CoordinatorTxs []common.L1Tx, addr *ethCommon.Address, bjj *babyjub.PublicKey) bool {
 	if addr == nil {
 		log.Warn("The provided addr is nil")
 		return false

txselector/txselector_test.go

@@ -35,9 +35,9 @@ func initTest(t *testing.T, testSet string) *TxSelector {
 
 	return txsel
 }
-func addL2Txs(t *testing.T, txsel *TxSelector, poolL2Txs []*common.PoolL2Tx) {
+func addL2Txs(t *testing.T, txsel *TxSelector, poolL2Txs []common.PoolL2Tx) {
 	for i := 0; i < len(poolL2Txs); i++ {
-		err := txsel.l2db.AddTxTest(poolL2Txs[i])
+		err := txsel.l2db.AddTxTest(&poolL2Txs[i])
 		require.Nil(t, err)
 	}
 }