internal/ethapi: support for beacon root and withdrawals in simulate api

internal/ethapi/override/override.go

@@ -128,6 +128,8 @@ type BlockOverrides struct {
 	PrevRandao    *common.Hash
 	BaseFeePerGas *hexutil.Big
 	BlobBaseFee   *hexutil.Big
+	BeaconRoot    *common.Hash
+	Withdrawals   *types.Withdrawals
 }
 
 // Apply overrides the given header fields into the given block context.

internal/ethapi/simulate.go

@@ -36,7 +36,6 @@ import (
 	"github.com/ethereum/go-ethereum/internal/ethapi/override"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/rpc"
-	"github.com/ethereum/go-ethereum/trie"
 )
 
 const (
@@ -95,6 +94,47 @@ type simOpts struct {
 	ReturnFullTransactions bool
 }
 
+// simChainHeadReader implements ChainHeaderReader which is needed as input for FinalizeAndAssemble.
+type simChainHeadReader struct {
+	context.Context
+	Backend
+}
+
+func (m *simChainHeadReader) Config() *params.ChainConfig {
+	return m.Backend.ChainConfig()
+}
+
+func (m *simChainHeadReader) CurrentHeader() *types.Header {
+	return m.Backend.CurrentHeader()
+}
+
+func (m *simChainHeadReader) GetHeader(hash common.Hash, number uint64) *types.Header {
+	header, err := m.Backend.HeaderByNumber(m.Context, rpc.BlockNumber(number))
+	if err != nil || header == nil {
+		return nil
+	}
+	if header.Hash() != hash {
+		return nil
+	}
+	return header
+}
+
+func (m *simChainHeadReader) GetHeaderByNumber(number uint64) *types.Header {
+	header, err := m.Backend.HeaderByNumber(m.Context, rpc.BlockNumber(number))
+	if err != nil {
+		return nil
+	}
+	return header
+}
+
+func (m *simChainHeadReader) GetHeaderByHash(hash common.Hash) *types.Header {
+	header, err := m.Backend.HeaderByHash(m.Context, hash)
+	if err != nil {
+		return nil
+	}
+	return header
+}
+
 // simulator is a stateful object that simulates a series of blocks.
 // it is not safe for concurrent use.
 type simulator struct {
@@ -209,6 +249,9 @@ func (sim *simulator) processBlock(ctx context.Context, block *simBlock, header,
 	if sim.chainConfig.IsPrague(header.Number, header.Time) || sim.chainConfig.IsVerkle(header.Number, header.Time) {
 		core.ProcessParentBlockHash(header.ParentHash, evm)
 	}
+	if block.BlockOverrides.BeaconRoot != nil {
+		core.ProcessBeaconBlockRoot(*block.BlockOverrides.BeaconRoot, evm)
+	}
 	var allLogs []*types.Log
 	for i, call := range block.Calls {
 		if err := ctx.Err(); err != nil {
@@ -258,6 +301,10 @@ func (sim *simulator) processBlock(ctx context.Context, block *simBlock, header,
 		}
 		callResults[i] = callRes
 	}
+	header.GasUsed = gasUsed
+	if sim.chainConfig.IsCancun(header.Number, header.Time) {
+		header.BlobGasUsed = &blobGasUsed
+	}
 	var requests [][]byte
 	// Process EIP-7685 requests
 	if sim.chainConfig.IsPrague(header.Number, header.Time) {
@@ -271,20 +318,16 @@ func (sim *simulator) processBlock(ctx context.Context, block *simBlock, header,
 		// EIP-7251
 		core.ProcessConsolidationQueue(&requests, evm)
 	}
-	header.Root = sim.state.IntermediateRoot(true)
-	header.GasUsed = gasUsed
-	if sim.chainConfig.IsCancun(header.Number, header.Time) {
-		header.BlobGasUsed = &blobGasUsed
-	}
-	var withdrawals types.Withdrawals
-	if sim.chainConfig.IsShanghai(header.Number, header.Time) {
-		withdrawals = make([]*types.Withdrawal, 0)
-	}
 	if requests != nil {
 		reqHash := types.CalcRequestsHash(requests)
 		header.RequestsHash = &reqHash
 	}
-	b := types.NewBlock(header, &types.Body{Transactions: txes, Withdrawals: withdrawals}, receipts, trie.NewStackTrie(nil))
+	blockBody := &types.Body{Transactions: txes, Withdrawals: *block.BlockOverrides.Withdrawals}
+	chainHeadReader := &simChainHeadReader{ctx, sim.b}
+	b, err := sim.b.Engine().FinalizeAndAssemble(chainHeadReader, header, sim.state, blockBody, receipts)
+	if err != nil {
+		return nil, nil, err
+	}
 	repairLogs(callResults, b.Hash())
 	return b, callResults, nil
 }
@@ -346,6 +389,9 @@ func (sim *simulator) sanitizeChain(blocks []simBlock) ([]simBlock, error) {
 			n := new(big.Int).Add(prevNumber, big.NewInt(1))
 			block.BlockOverrides.Number = (*hexutil.Big)(n)
 		}
+		if block.BlockOverrides.Withdrawals == nil {
+			block.BlockOverrides.Withdrawals = &types.Withdrawals{}
+		}
 		diff := new(big.Int).Sub(block.BlockOverrides.Number.ToInt(), prevNumber)
 		if diff.Cmp(common.Big0) <= 0 {
 			return nil, &invalidBlockNumberError{fmt.Sprintf("block numbers must be in order: %d <= %d", block.BlockOverrides.Number.ToInt().Uint64(), prevNumber)}
@@ -360,7 +406,13 @@ func (sim *simulator) sanitizeChain(blocks []simBlock) ([]simBlock, error) {
 			for i := uint64(0); i < gap.Uint64(); i++ {
 				n := new(big.Int).Add(prevNumber, big.NewInt(int64(i+1)))
 				t := prevTimestamp + timestampIncrement
-				b := simBlock{BlockOverrides: &override.BlockOverrides{Number: (*hexutil.Big)(n), Time: (*hexutil.Uint64)(&t)}}
+				b := simBlock{
+					BlockOverrides: &override.BlockOverrides{
+						Number:      (*hexutil.Big)(n),
+						Time:        (*hexutil.Uint64)(&t),
+						Withdrawals: &types.Withdrawals{},
+					},
+				}
 				prevTimestamp = t
 				res = append(res, b)
 			}