fix estimate gas nonce computation to deal with sequencer concurrency (…

…0xPolygonHermez#2204)

state/transaction.go

@@ -758,21 +758,6 @@ func (s *State) internalProcessUnsignedTransaction(ctx context.Context, tx *type
 		return nil, err
 	}
 
-	stateRoot := l2BlockStateRoot
-	if l2BlockNumber != nil {
-		l2Block, err := s.GetL2BlockByNumber(ctx, *l2BlockNumber, dbTx)
-		if err != nil {
-			return nil, err
-		}
-		stateRoot = l2Block.Root()
-	}
-
-	loadedNonce, err := s.tree.GetNonce(ctx, senderAddress, stateRoot.Bytes())
-	if err != nil {
-		return nil, err
-	}
-	nonce := loadedNonce.Uint64()
-
 	// Get latest batch from the database to get globalExitRoot and Timestamp
 	lastBatch := lastBatches[0]
 
@@ -782,9 +767,15 @@ func (s *State) internalProcessUnsignedTransaction(ctx context.Context, tx *type
 		previousBatch = lastBatches[1]
 	}
 
+	stateRoot := l2BlockStateRoot
 	timestamp := uint64(lastBatch.Timestamp.Unix())
-
 	if l2BlockNumber != nil {
+		l2Block, err := s.GetL2BlockByNumber(ctx, *l2BlockNumber, dbTx)
+		if err != nil {
+			return nil, err
+		}
+		stateRoot = l2Block.Root()
+
 		latestL2BlockNumber, err := s.PostgresStorage.GetLastL2BlockNumber(ctx, dbTx)
 		if err != nil {
 			return nil, err
@@ -796,6 +787,11 @@ func (s *State) internalProcessUnsignedTransaction(ctx context.Context, tx *type
 	}
 
 	forkID := s.GetForkIDByBatchNumber(lastBatch.BatchNumber)
+	loadedNonce, err := s.tree.GetNonce(ctx, senderAddress, stateRoot.Bytes())
+	if err != nil {
+		return nil, err
+	}
+	nonce := loadedNonce.Uint64()
 
 	batchL2Data, err := EncodeUnsignedTransaction(*tx, s.cfg.ChainID, &nonce, forkID)
 	if err != nil {
@@ -963,6 +959,21 @@ func (s *State) EstimateGas(transaction *types.Transaction, senderAddress common
 		return 0, nil, err
 	}
 
+	stateRoot := l2BlockStateRoot
+	if l2BlockNumber != nil {
+		l2Block, err := s.GetL2BlockByNumber(ctx, *l2BlockNumber, dbTx)
+		if err != nil {
+			return 0, nil, err
+		}
+		stateRoot = l2Block.Root()
+	}
+
+	loadedNonce, err := s.tree.GetNonce(ctx, senderAddress, stateRoot.Bytes())
+	if err != nil {
+		return 0, nil, err
+	}
+	nonce := loadedNonce.Uint64()
+
 	// Get latest batch from the database to get globalExitRoot and Timestamp
 	lastBatch := lastBatches[0]
 
@@ -978,7 +989,7 @@ func (s *State) EstimateGas(transaction *types.Transaction, senderAddress common
 	}
 
 	if lowEnd == ethTransferGas && transaction.To() != nil {
-		code, err := s.tree.GetCode(ctx, *transaction.To(), l2BlockStateRoot.Bytes())
+		code, err := s.tree.GetCode(ctx, *transaction.To(), stateRoot.Bytes())
 		if err != nil {
 			log.Warnf("error while getting transaction.to() code %v", err)
 		} else if len(code) == 0 {
@@ -995,7 +1006,7 @@ func (s *State) EstimateGas(transaction *types.Transaction, senderAddress common
 	var availableBalance *big.Int
 
 	if senderAddress != ZeroAddress {
-		senderBalance, err := s.tree.GetBalance(ctx, senderAddress, l2BlockStateRoot.Bytes())
+		senderBalance, err := s.tree.GetBalance(ctx, senderAddress, stateRoot.Bytes())
 		if err != nil {
 			if errors.Is(err, ErrNotFound) {
 				senderBalance = big.NewInt(0)
@@ -1029,9 +1040,9 @@ func (s *State) EstimateGas(transaction *types.Transaction, senderAddress common
 
 	// Run the transaction with the specified gas value.
 	// Returns a status indicating if the transaction failed, if it was reverted and the accompanying error
-	testTransaction := func(gas uint64, shouldOmitErr bool) (failed, reverted bool, gasUsed uint64, returnValue []byte, err error) {
+	testTransaction := func(gas uint64, nonce uint64, shouldOmitErr bool) (failed, reverted bool, gasUsed uint64, returnValue []byte, err error) {
 		tx := types.NewTx(&types.LegacyTx{
-			Nonce:    transaction.Nonce(),
+			Nonce:    nonce,
 			To:       transaction.To(),
 			Value:    transaction.Value(),
 			Gas:      gas,
@@ -1052,7 +1063,7 @@ func (s *State) EstimateGas(transaction *types.Transaction, senderAddress common
 			OldBatchNum:      lastBatch.BatchNumber,
 			BatchL2Data:      batchL2Data,
 			From:             senderAddress.String(),
-			OldStateRoot:     l2BlockStateRoot.Bytes(),
+			OldStateRoot:     stateRoot.Bytes(),
 			GlobalExitRoot:   lastBatch.GlobalExitRoot.Bytes(),
 			OldAccInputHash:  previousBatch.AccInputHash.Bytes(),
 			EthTimestamp:     uint64(lastBatch.Timestamp.Unix()),
@@ -1116,7 +1127,7 @@ func (s *State) EstimateGas(transaction *types.Transaction, senderAddress common
 	var totalExecutionTime time.Duration
 
 	// Check if the highEnd is a good value to make the transaction pass
-	failed, reverted, gasUsed, returnValue, err := testTransaction(highEnd, false)
+	failed, reverted, gasUsed, returnValue, err := testTransaction(highEnd, nonce, false)
 	log.Debugf("Estimate gas. Trying to execute TX with %v gas", highEnd)
 	if failed {
 		if reverted {
@@ -1142,7 +1153,7 @@ func (s *State) EstimateGas(transaction *types.Transaction, senderAddress common
 
 		log.Debugf("Estimate gas. Trying to execute TX with %v gas", mid)
 
-		failed, reverted, _, _, testErr := testTransaction(mid, true)
+		failed, reverted, _, _, testErr := testTransaction(mid, nonce, true)
 		executionTime := time.Since(txExecutionStart)
 		totalExecutionTime += executionTime
 		txExecutions = append(txExecutions, executionTime)