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simulated.go
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simulated.go
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// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package backends
import (
"context"
"errors"
"fmt"
"math/big"
"sync"
"testing"
"time"
"github.com/holiman/uint256"
"github.com/ledgerwatch/log/v3"
"github.com/nebojsa94/erigon/erigon-lib/chain"
libcommon "github.com/nebojsa94/erigon/erigon-lib/common"
"github.com/nebojsa94/erigon/erigon-lib/common/hexutility"
"github.com/nebojsa94/erigon/erigon-lib/kv"
state2 "github.com/nebojsa94/erigon/erigon-lib/state"
types2 "github.com/nebojsa94/erigon/erigon-lib/types"
ethereum "github.com/nebojsa94/erigon"
"github.com/nebojsa94/erigon/accounts/abi"
"github.com/nebojsa94/erigon/accounts/abi/bind"
"github.com/nebojsa94/erigon/common/math"
"github.com/nebojsa94/erigon/common/u256"
"github.com/nebojsa94/erigon/consensus"
"github.com/nebojsa94/erigon/consensus/ethash"
"github.com/nebojsa94/erigon/consensus/misc"
"github.com/nebojsa94/erigon/core"
"github.com/nebojsa94/erigon/core/rawdb"
"github.com/nebojsa94/erigon/core/state"
"github.com/nebojsa94/erigon/core/types"
"github.com/nebojsa94/erigon/core/vm"
"github.com/nebojsa94/erigon/event"
"github.com/nebojsa94/erigon/params"
"github.com/nebojsa94/erigon/turbo/services"
"github.com/nebojsa94/erigon/turbo/stages/mock"
)
// This nil assignment ensures at compile time that SimulatedBackend implements bind.ContractBackend.
var _ bind.ContractBackend = (*SimulatedBackend)(nil)
var (
errBlockNumberUnsupported = errors.New("simulatedBackend cannot access blocks other than the latest block")
errBlockDoesNotExist = errors.New("block does not exist in blockchain")
errTransactionDoesNotExist = errors.New("transaction does not exist")
)
// SimulatedBackend implements bind.ContractBackend, simulating a blockchain in
// the background. Its main purpose is to allow for easy testing of contract bindings.
// Simulated backend implements the following interfaces:
// ChainReader, ChainStateReader, ContractBackend, ContractCaller, ContractFilterer, ContractTransactor,
// DeployBackend, GasEstimator, GasPricer, LogFilterer, PendingContractCaller, TransactionReader, and TransactionSender
type SimulatedBackend struct {
m *mock.MockSentry
getHeader func(hash libcommon.Hash, number uint64) *types.Header
mu sync.Mutex
prependBlock *types.Block
pendingReceipts types.Receipts
pendingHeader *types.Header
gasPool *core.GasPool
pendingBlock *types.Block // Currently pending block that will be imported on request
pendingReader state.StateReader
pendingReaderTx kv.Tx
pendingState *state.IntraBlockState // Currently pending state that will be the active on request
rmLogsFeed event.Feed
chainFeed event.Feed
logsFeed event.Feed
}
// NewSimulatedBackend creates a new binding backend using a simulated blockchain
// for testing purposes.
func NewSimulatedBackendWithConfig(alloc types.GenesisAlloc, config *chain.Config, gasLimit uint64) *SimulatedBackend {
genesis := types.Genesis{Config: config, GasLimit: gasLimit, Alloc: alloc}
engine := ethash.NewFaker()
checkStateRoot := true
m := mock.MockWithGenesisEngine(nil, &genesis, engine, false, checkStateRoot)
backend := &SimulatedBackend{
m: m,
prependBlock: m.Genesis,
getHeader: func(hash libcommon.Hash, number uint64) (h *types.Header) {
var err error
if err = m.DB.View(context.Background(), func(tx kv.Tx) error {
h, err = m.BlockReader.Header(context.Background(), tx, hash, number)
return nil
}); err != nil {
panic(err)
}
return h
},
}
backend.emptyPendingBlock()
return backend
}
// A simulated backend always uses chainID 1337.
func NewSimulatedBackend(t *testing.T, alloc types.GenesisAlloc, gasLimit uint64) *SimulatedBackend {
b := NewSimulatedBackendWithConfig(alloc, params.TestChainConfig, gasLimit)
t.Cleanup(b.Close)
return b
}
func NewTestSimulatedBackendWithConfig(t *testing.T, alloc types.GenesisAlloc, config *chain.Config, gasLimit uint64) *SimulatedBackend {
b := NewSimulatedBackendWithConfig(alloc, config, gasLimit)
t.Cleanup(b.Close)
return b
}
func (b *SimulatedBackend) DB() kv.RwDB { return b.m.DB }
func (b *SimulatedBackend) Agg() *state2.AggregatorV3 { return b.m.HistoryV3Components() }
func (b *SimulatedBackend) HistoryV3() bool { return b.m.HistoryV3 }
func (b *SimulatedBackend) Engine() consensus.Engine { return b.m.Engine }
func (b *SimulatedBackend) BlockReader() services.FullBlockReader { return b.m.BlockReader }
// Close terminates the underlying blockchain's update loop.
func (b *SimulatedBackend) Close() {
if b.pendingReaderTx != nil {
b.pendingReaderTx.Rollback()
}
b.m.Close()
}
// Commit imports all the pending transactions as a single block and starts a
// fresh new state.
func (b *SimulatedBackend) Commit() {
b.mu.Lock()
defer b.mu.Unlock()
if err := b.m.InsertChain(&core.ChainPack{
Headers: []*types.Header{b.pendingHeader},
Blocks: []*types.Block{b.pendingBlock},
TopBlock: b.pendingBlock,
}); err != nil {
panic(err)
}
//nolint:prealloc
var allLogs []*types.Log
for _, r := range b.pendingReceipts {
allLogs = append(allLogs, r.Logs...)
}
b.logsFeed.Send(allLogs)
b.prependBlock = b.pendingBlock
b.emptyPendingBlock()
}
// Rollback aborts all pending transactions, reverting to the last committed state.
func (b *SimulatedBackend) Rollback() {
b.mu.Lock()
defer b.mu.Unlock()
b.emptyPendingBlock()
}
func (b *SimulatedBackend) emptyPendingBlock() {
blockChain, _ := core.GenerateChain(b.m.ChainConfig, b.prependBlock, b.m.Engine, b.m.DB, 1, func(int, *core.BlockGen) {})
b.pendingBlock = blockChain.Blocks[0]
b.pendingReceipts = blockChain.Receipts[0]
b.pendingHeader = blockChain.Headers[0]
b.gasPool = new(core.GasPool).AddGas(b.pendingHeader.GasLimit).AddBlobGas(b.m.ChainConfig.GetMaxBlobGasPerBlock())
if b.pendingReaderTx != nil {
b.pendingReaderTx.Rollback()
}
tx, err := b.m.DB.BeginRo(context.Background()) //nolint:gocritic
if err != nil {
panic(err)
}
b.pendingReaderTx = tx
b.pendingReader = b.m.NewStateReader(b.pendingReaderTx)
b.pendingState = state.New(b.pendingReader)
}
// stateByBlockNumber retrieves a state by a given blocknumber.
func (b *SimulatedBackend) stateByBlockNumber(db kv.Tx, blockNumber *big.Int) *state.IntraBlockState {
if blockNumber == nil || blockNumber.Cmp(b.pendingBlock.Number()) == 0 {
return state.New(b.m.NewHistoryStateReader(b.pendingBlock.NumberU64()+1, db))
}
return state.New(b.m.NewHistoryStateReader(blockNumber.Uint64()+1, db))
}
// CodeAt returns the code associated with a certain account in the blockchain.
func (b *SimulatedBackend) CodeAt(ctx context.Context, contract libcommon.Address, blockNumber *big.Int) ([]byte, error) {
b.mu.Lock()
defer b.mu.Unlock()
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return nil, err
}
defer tx.Rollback()
stateDB := b.stateByBlockNumber(tx, blockNumber)
return stateDB.GetCode(contract), nil
}
// BalanceAt returns the wei balance of a certain account in the blockchain.
func (b *SimulatedBackend) BalanceAt(ctx context.Context, contract libcommon.Address, blockNumber *big.Int) (*uint256.Int, error) {
b.mu.Lock()
defer b.mu.Unlock()
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return nil, err
}
defer tx.Rollback()
stateDB := b.stateByBlockNumber(tx, blockNumber)
return stateDB.GetBalance(contract), nil
}
// NonceAt returns the nonce of a certain account in the blockchain.
func (b *SimulatedBackend) NonceAt(ctx context.Context, contract libcommon.Address, blockNumber *big.Int) (uint64, error) {
b.mu.Lock()
defer b.mu.Unlock()
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return 0, err
}
defer tx.Rollback()
stateDB := b.stateByBlockNumber(tx, blockNumber)
return stateDB.GetNonce(contract), nil
}
// StorageAt returns the value of key in the storage of an account in the blockchain.
func (b *SimulatedBackend) StorageAt(ctx context.Context, contract libcommon.Address, key libcommon.Hash, blockNumber *big.Int) ([]byte, error) {
b.mu.Lock()
defer b.mu.Unlock()
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return nil, err
}
defer tx.Rollback()
stateDB := b.stateByBlockNumber(tx, blockNumber)
var val uint256.Int
stateDB.GetState(contract, &key, &val)
return val.Bytes(), nil
}
// TransactionReceipt returns the receipt of a transaction.
func (b *SimulatedBackend) TransactionReceipt(ctx context.Context, txHash libcommon.Hash) (*types.Receipt, error) {
b.mu.Lock()
defer b.mu.Unlock()
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return nil, err
}
defer tx.Rollback()
// Retrieve the context of the receipt based on the transaction hash
blockNumber, err := rawdb.ReadTxLookupEntry(tx, txHash)
if err != nil {
return nil, err
}
if blockNumber == nil {
return nil, nil
}
block, err := b.BlockReader().BlockByNumber(b.m.Ctx, tx, *blockNumber)
if err != nil {
return nil, err
}
// Read all the receipts from the block and return the one with the matching hash
receipts := rawdb.ReadReceipts(tx, block, nil)
for _, receipt := range receipts {
if receipt.TxHash == txHash {
return receipt, nil
}
}
return nil, nil
}
// TransactionByHash checks the pool of pending transactions in addition to the
// blockchain. The isPending return value indicates whether the transaction has been
// mined yet. Note that the transaction may not be part of the canonical chain even if
// it's not pending.
func (b *SimulatedBackend) TransactionByHash(ctx context.Context, txHash libcommon.Hash) (types.Transaction, bool, error) {
b.mu.Lock()
defer b.mu.Unlock()
tx, err := b.m.DB.BeginRo(ctx)
if err != nil {
return nil, false, err
}
defer tx.Rollback()
txn := b.pendingBlock.Transaction(txHash)
if txn != nil {
return txn, true, nil
}
blockNumber, ok, err := b.BlockReader().TxnLookup(ctx, tx, txHash)
if err != nil {
return nil, false, err
}
if !ok {
return nil, false, ethereum.NotFound
}
blockHash, err := b.BlockReader().CanonicalHash(ctx, tx, blockNumber)
if err != nil {
return nil, false, err
}
body, err := b.BlockReader().BodyWithTransactions(ctx, tx, blockHash, blockNumber)
if err != nil {
return nil, false, err
}
if body == nil {
return nil, false, ethereum.NotFound
}
for _, txn = range body.Transactions {
if txn.Hash() == txHash {
return txn, false, nil
}
}
return nil, false, ethereum.NotFound
}
// BlockByHash retrieves a block based on the block hash.
func (b *SimulatedBackend) BlockByHash(ctx context.Context, hash libcommon.Hash) (*types.Block, error) {
b.mu.Lock()
defer b.mu.Unlock()
if hash == b.pendingBlock.Hash() {
return b.pendingBlock, nil
}
tx, err := b.m.DB.BeginRo(ctx)
if err != nil {
return nil, err
}
defer tx.Rollback()
block, err := b.BlockReader().BlockByHash(ctx, tx, hash)
if err != nil {
return nil, err
}
if block != nil {
return block, nil
}
return nil, errBlockDoesNotExist
}
// BlockByNumber retrieves a block from the database by number, caching it
// (associated with its hash) if found.
func (b *SimulatedBackend) BlockByNumber(ctx context.Context, number *big.Int) (*types.Block, error) {
b.mu.Lock()
defer b.mu.Unlock()
return b.blockByNumberNoLock(ctx, number)
}
// blockByNumberNoLock retrieves a block from the database by number, caching it
// (associated with its hash) if found without Lock.
func (b *SimulatedBackend) blockByNumberNoLock(ctx context.Context, number *big.Int) (*types.Block, error) {
if number == nil || number.Cmp(b.prependBlock.Number()) == 0 {
return b.prependBlock, nil
}
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return nil, err
}
defer tx.Rollback()
block, err := b.BlockReader().BlockByNumber(ctx, tx, number.Uint64())
if err != nil {
return nil, err
}
if block == nil {
return nil, errBlockDoesNotExist
}
return block, nil
}
// HeaderByHash returns a block header from the current canonical chain.
func (b *SimulatedBackend) HeaderByHash(ctx context.Context, hash libcommon.Hash) (*types.Header, error) {
b.mu.Lock()
defer b.mu.Unlock()
if hash == b.pendingBlock.Hash() {
return b.pendingBlock.Header(), nil
}
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return nil, err
}
defer tx.Rollback()
number := rawdb.ReadHeaderNumber(tx, hash)
if number == nil {
return nil, errBlockDoesNotExist
}
header, err := b.BlockReader().Header(ctx, tx, hash, *number)
if err != nil {
return nil, err
}
if header == nil {
return nil, errBlockDoesNotExist
}
return header, nil
}
// HeaderByNumber returns a block header from the current canonical chain. If number is
// nil, the latest known header is returned.
func (b *SimulatedBackend) HeaderByNumber(ctx context.Context, number *big.Int) (*types.Header, error) {
b.mu.Lock()
defer b.mu.Unlock()
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return nil, err
}
defer tx.Rollback()
if number == nil || number.Cmp(b.prependBlock.Number()) == 0 {
return b.prependBlock.Header(), nil
}
header, err := b.BlockReader().HeaderByNumber(ctx, tx, number.Uint64())
if err != nil {
return nil, err
}
return header, nil
}
// TransactionCount returns the number of transactions in a given block.
func (b *SimulatedBackend) TransactionCount(ctx context.Context, blockHash libcommon.Hash) (uint, error) {
b.mu.Lock()
defer b.mu.Unlock()
if blockHash == b.pendingBlock.Hash() {
return uint(b.pendingBlock.Transactions().Len()), nil
}
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return 0, err
}
defer tx.Rollback()
blockNum := rawdb.ReadHeaderNumber(tx, blockHash)
if blockNum == nil {
return 0, nil
}
block, _, err := b.BlockReader().BlockWithSenders(ctx, tx, blockHash, *blockNum)
if err != nil {
return 0, err
}
if block == nil {
return uint(0), errBlockDoesNotExist
}
return uint(block.Transactions().Len()), nil
}
// TransactionInBlock returns the transaction for a specific block at a specific index.
func (b *SimulatedBackend) TransactionInBlock(ctx context.Context, blockHash libcommon.Hash, index uint) (types.Transaction, error) {
b.mu.Lock()
defer b.mu.Unlock()
if blockHash == b.pendingBlock.Hash() {
transactions := b.pendingBlock.Transactions()
if uint(len(transactions)) < index+1 {
return nil, errTransactionDoesNotExist
}
return transactions[index], nil
}
tx, err := b.m.DB.BeginRo(context.Background())
if err != nil {
return nil, err
}
defer tx.Rollback()
blockNum := rawdb.ReadHeaderNumber(tx, blockHash)
if blockNum == nil {
return nil, nil
}
block, _, err := b.BlockReader().BlockWithSenders(ctx, tx, blockHash, *blockNum)
if err != nil {
return nil, err
}
if block == nil {
return nil, errBlockDoesNotExist
}
transactions := block.Transactions()
if uint(len(transactions)) < index+1 {
return nil, errTransactionDoesNotExist
}
return transactions[index], nil
}
// PendingCodeAt returns the code associated with an account in the pending state.
func (b *SimulatedBackend) PendingCodeAt(ctx context.Context, contract libcommon.Address) ([]byte, error) {
b.mu.Lock()
defer b.mu.Unlock()
return b.pendingState.GetCode(contract), nil
}
func newRevertError(result *core.ExecutionResult) *revertError {
reason, errUnpack := abi.UnpackRevert(result.Revert())
err := errors.New("execution reverted")
if errUnpack == nil {
err = fmt.Errorf("execution reverted: %v", reason)
}
return &revertError{
error: err,
reason: hexutility.Encode(result.Revert()),
}
}
// revertError is an API error that encompasses an EVM revert with JSON error
// code and a binary data blob.
type revertError struct {
error
reason string // revert reason hex encoded
}
// ErrorCode returns the JSON error code for a revert.
// See: https://github.com/ethereum/wiki/wiki/JSON-RPC-Error-Codes-Improvement-Proposal
func (e *revertError) ErrorCode() int {
return 3
}
// ErrorData returns the hex encoded revert reason.
func (e *revertError) ErrorData() interface{} {
return e.reason
}
// CallContract executes a contract call.
func (b *SimulatedBackend) CallContract(ctx context.Context, call ethereum.CallMsg, blockNumber *big.Int) ([]byte, error) {
b.mu.Lock()
defer b.mu.Unlock()
if blockNumber != nil && blockNumber.Cmp(b.pendingBlock.Number()) != 0 {
return nil, errBlockNumberUnsupported
}
var res *core.ExecutionResult
if err := b.m.DB.View(context.Background(), func(tx kv.Tx) (err error) {
s := state.New(b.m.NewStateReader(tx))
res, err = b.callContract(ctx, call, b.pendingBlock, s)
if err != nil {
return err
}
return nil
}); err != nil {
return nil, err
}
// If the result contains a revert reason, try to unpack and return it.
if len(res.Revert()) > 0 {
return nil, newRevertError(res)
}
return res.Return(), res.Err
}
// PendingCallContract executes a contract call on the pending state.
func (b *SimulatedBackend) PendingCallContract(ctx context.Context, call ethereum.CallMsg) ([]byte, error) {
b.mu.Lock()
defer b.mu.Unlock()
defer b.pendingState.RevertToSnapshot(b.pendingState.Snapshot())
res, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
if err != nil {
return nil, err
}
// If the result contains a revert reason, try to unpack and return it.
if len(res.Revert()) > 0 {
return nil, newRevertError(res)
}
return res.Return(), res.Err
}
// PendingNonceAt implements PendingStateReader.PendingNonceAt, retrieving
// the nonce currently pending for the account.
func (b *SimulatedBackend) PendingNonceAt(ctx context.Context, account libcommon.Address) (uint64, error) {
b.mu.Lock()
defer b.mu.Unlock()
return b.pendingState.GetNonce(account), nil
}
// SuggestGasPrice implements ContractTransactor.SuggestGasPrice. Since the simulated
// chain doesn't have miners, we just return a gas price of 1 for any call.
func (b *SimulatedBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error) {
return big.NewInt(1), nil
}
// EstimateGas executes the requested code against the currently pending block/state and
// returns the used amount of gas.
func (b *SimulatedBackend) EstimateGas(ctx context.Context, call ethereum.CallMsg) (uint64, error) {
b.mu.Lock()
defer b.mu.Unlock()
// Determine the lowest and highest possible gas limits to binary search in between
var (
lo = params.TxGas - 1
hi uint64
gasCap uint64
)
if call.Gas >= params.TxGas {
hi = call.Gas
} else {
hi = b.pendingBlock.GasLimit()
}
// Recap the highest gas allowance with account's balance.
if call.GasPrice != nil && !call.GasPrice.IsZero() {
balance := b.pendingState.GetBalance(call.From) // from can't be nil
available := balance.ToBig()
if call.Value != nil {
if call.Value.ToBig().Cmp(available) >= 0 {
return 0, errors.New("insufficient funds for transfer")
}
available.Sub(available, call.Value.ToBig())
}
allowance := new(big.Int).Div(available, call.GasPrice.ToBig())
if allowance.IsUint64() && hi > allowance.Uint64() {
transfer := call.Value
if transfer == nil {
transfer = new(uint256.Int)
}
log.Warn("Gas estimation capped by limited funds", "original", hi, "balance", balance,
"sent", transfer, "gasprice", call.GasPrice, "fundable", allowance)
hi = allowance.Uint64()
}
}
gasCap = hi
b.pendingState.SetTxContext(libcommon.Hash{}, libcommon.Hash{}, len(b.pendingBlock.Transactions()))
// Create a helper to check if a gas allowance results in an executable transaction
executable := func(gas uint64) (bool, *core.ExecutionResult, error) {
call.Gas = gas
snapshot := b.pendingState.Snapshot()
res, err := b.callContract(ctx, call, b.pendingBlock, b.pendingState)
b.pendingState.RevertToSnapshot(snapshot)
if err != nil {
if errors.Is(err, core.ErrIntrinsicGas) {
return true, nil, nil // Special case, raise gas limit
}
return true, nil, err // Bail out
}
return res.Failed(), res, nil
}
// Execute the binary search and hone in on an executable gas limit
for lo+1 < hi {
mid := (hi + lo) / 2
failed, _, err := executable(mid)
// If the error is not nil(consensus error), it means the provided message
// call or transaction will never be accepted no matter how much gas it is
// assigned. Return the error directly, don't struggle any more
if err != nil {
return 0, err
}
if failed {
lo = mid
} else {
hi = mid
}
}
// Reject the transaction as invalid if it still fails at the highest allowance
if hi == gasCap {
failed, result, err := executable(hi)
if err != nil {
return 0, err
}
if failed {
if result != nil && result.Err != vm.ErrOutOfGas {
if len(result.Revert()) > 0 {
return 0, newRevertError(result)
}
return 0, result.Err
}
// Otherwise, the specified gas cap is too low
return 0, fmt.Errorf("gas required exceeds allowance (%d)", gasCap)
}
}
return hi, nil
}
// callContract implements common code between normal and pending contract calls.
// state is modified during execution, make sure to copy it if necessary.
func (b *SimulatedBackend) callContract(_ context.Context, call ethereum.CallMsg, block *types.Block, statedb *state.IntraBlockState) (*core.ExecutionResult, error) {
const baseFeeUpperLimit = 880000000
// Ensure message is initialized properly.
if call.GasPrice == nil {
call.GasPrice = u256.Num1
}
if call.FeeCap == nil {
call.FeeCap = uint256.NewInt(baseFeeUpperLimit)
}
if call.Tip == nil {
call.Tip = uint256.NewInt(baseFeeUpperLimit)
}
if call.Gas == 0 {
call.Gas = 50000000
}
if call.Value == nil {
call.Value = new(uint256.Int)
}
// Set infinite balance to the fake caller account.
from := statedb.GetOrNewStateObject(call.From)
from.SetBalance(uint256.NewInt(0).SetAllOne())
// Execute the call.
msg := callMsg{call}
txContext := core.NewEVMTxContext(msg)
header := block.Header()
evmContext := core.NewEVMBlockContext(header, core.GetHashFn(header, b.getHeader), b.m.Engine, nil)
// Create a new environment which holds all relevant information
// about the transaction and calling mechanisms.
vmEnv := vm.NewEVM(evmContext, txContext, statedb, b.m.ChainConfig, vm.Config{})
gasPool := new(core.GasPool).AddGas(math.MaxUint64).AddBlobGas(math.MaxUint64)
return core.NewStateTransition(vmEnv, msg, gasPool).TransitionDb(true /* refunds */, false /* gasBailout */)
}
// SendTransaction updates the pending block to include the given transaction.
// It panics if the transaction is invalid.
func (b *SimulatedBackend) SendTransaction(ctx context.Context, tx types.Transaction) error {
b.mu.Lock()
defer b.mu.Unlock()
// Check transaction validity.
signer := types.MakeSigner(b.m.ChainConfig, b.pendingBlock.NumberU64(), b.pendingBlock.Time())
sender, senderErr := tx.Sender(*signer)
if senderErr != nil {
return fmt.Errorf("invalid transaction: %w", senderErr)
}
nonce := b.pendingState.GetNonce(sender)
if tx.GetNonce() != nonce {
return fmt.Errorf("invalid transaction nonce: got %d, want %d", tx.GetNonce(), nonce)
}
b.pendingState.SetTxContext(tx.Hash(), libcommon.Hash{}, len(b.pendingBlock.Transactions()))
//fmt.Printf("==== Start producing block %d, header: %d\n", b.pendingBlock.NumberU64(), b.pendingHeader.Number.Uint64())
if _, _, err := core.ApplyTransaction(
b.m.ChainConfig, core.GetHashFn(b.pendingHeader, b.getHeader), b.m.Engine,
&b.pendingHeader.Coinbase, b.gasPool,
b.pendingState, state.NewNoopWriter(),
b.pendingHeader, tx,
&b.pendingHeader.GasUsed, b.pendingHeader.BlobGasUsed,
vm.Config{}); err != nil {
return err
}
//fmt.Printf("==== Start producing block %d\n", (b.prependBlock.NumberU64() + 1))
chain, err := core.GenerateChain(b.m.ChainConfig, b.prependBlock, b.m.Engine, b.m.DB, 1, func(number int, block *core.BlockGen) {
for _, tx := range b.pendingBlock.Transactions() {
block.AddTxWithChain(b.getHeader, b.m.Engine, tx)
}
block.AddTxWithChain(b.getHeader, b.m.Engine, tx)
})
if err != nil {
return err
}
//fmt.Printf("==== End producing block %d\n", b.pendingBlock.NumberU64())
b.pendingBlock = chain.Blocks[0]
b.pendingReceipts = chain.Receipts[0]
b.pendingHeader = chain.Headers[0]
return nil
}
// FilterLogs executes a log filter operation, blocking during execution and
// returning all the results in one batch.
//
// TODO(karalabe): Deprecate when the subscription one can return past data too.
func (b *SimulatedBackend) FilterLogs(ctx context.Context, query ethereum.FilterQuery) ([]types.Log, error) {
return nil, nil
}
// SubscribeFilterLogs creates a background log filtering operation, returning a
// subscription immediately, which can be used to stream the found events.
func (b *SimulatedBackend) SubscribeFilterLogs(ctx context.Context, query ethereum.FilterQuery, ch chan<- types.Log) (ethereum.Subscription, error) {
return nil, nil
}
// SubscribeNewHead returns an event subscription for a new header.
func (b *SimulatedBackend) SubscribeNewHead(ctx context.Context, ch chan<- *types.Header) (ethereum.Subscription, error) {
return nil, nil
}
// AdjustTime adds a time shift to the simulated clock.
// It can only be called on empty blocks.
func (b *SimulatedBackend) AdjustTime(adjustment time.Duration) error {
b.mu.Lock()
defer b.mu.Unlock()
if len(b.pendingBlock.Transactions()) != 0 {
return errors.New("could not adjust time on non-empty block")
}
chain, err := core.GenerateChain(b.m.ChainConfig, b.prependBlock, b.m.Engine, b.m.DB, 1, func(number int, block *core.BlockGen) {
for _, tx := range b.pendingBlock.Transactions() {
block.AddTxWithChain(b.getHeader, b.m.Engine, tx)
}
block.OffsetTime(int64(adjustment.Seconds()))
})
if err != nil {
return err
}
b.pendingBlock = chain.Blocks[0]
b.pendingHeader = chain.Headers[0]
return nil
}
// callMsg implements core.Message to allow passing it as a transaction simulator.
type callMsg struct {
ethereum.CallMsg
}
func (m callMsg) From() libcommon.Address { return m.CallMsg.From }
func (m callMsg) Nonce() uint64 { return 0 }
func (m callMsg) CheckNonce() bool { return false }
func (m callMsg) To() *libcommon.Address { return m.CallMsg.To }
func (m callMsg) GasPrice() *uint256.Int { return m.CallMsg.GasPrice }
func (m callMsg) FeeCap() *uint256.Int { return m.CallMsg.FeeCap }
func (m callMsg) Tip() *uint256.Int { return m.CallMsg.Tip }
func (m callMsg) Gas() uint64 { return m.CallMsg.Gas }
func (m callMsg) Value() *uint256.Int { return m.CallMsg.Value }
func (m callMsg) Data() []byte { return m.CallMsg.Data }
func (m callMsg) AccessList() types2.AccessList { return m.CallMsg.AccessList }
func (m callMsg) IsFree() bool { return false }
func (m callMsg) BlobGas() uint64 { return misc.GetBlobGasUsed(len(m.CallMsg.BlobHashes)) }
func (m callMsg) MaxFeePerBlobGas() *uint256.Int { return m.CallMsg.MaxFeePerBlobGas }
func (m callMsg) BlobHashes() []libcommon.Hash { return m.CallMsg.BlobHashes }