go-ethereum SimulatedBackend报max fee per gas低于block base fee错误如何解决

问题根因 #

• 报错确实和以太坊伦敦升级引入的EIP1559机制相关：新版本的go-ethereum SimulatedBackend默认启用了base fee规则，所有交易的maxFeePerGas必须大于等于当前区块的base fee才能被打包。
• 你设置auth.GasFeeCap不生效的核心原因是：你没有使用auth对象构造交易，而是手动调用types.NewTransaction创建了legacy类型的交易，auth的配置完全没有被用到。
• 当前你构造的legacy交易中，gasPrice仅为1 wei，远低于区块的base fee（875000000 wei），所以触发panic。

修复方案 #

这里给出两种可正常运行的实现方式：

方式1：直接使用TransactOpts发送交易（更简便） #

不用手动构造交易，直接用bind包的TransactOpts相关逻辑，配置会自动生效：

package eth

import (
	"context"
	"math/big"
	"testing"

	"github.com/ethereum/go-ethereum/accounts/abi/bind"
	"github.com/ethereum/go-ethereum/accounts/abi/bind/backends"
	"github.com/ethereum/go-ethereum/common"
	"github.com/ethereum/go-ethereum/core"
	"github.com/ethereum/go-ethereum/crypto"
)

func TestSimulatedBackend(t *testing.T) {
	privateKey, err := crypto.GenerateKey()
	if err != nil {
		t.Fatalf("failed to generate key: %v", err)
	}

	auth, err := bind.NewKeyedTransactorWithChainID(privateKey, big.NewInt(1337))
	if err != nil {
		t.Fatalf("failed to generate transactor: %v", err)
	}
	// 这里配置的GasFeeCap才会生效
	auth.GasFeeCap = big.NewInt(1000000000) // 1gwei，高于base fee即可
	auth.GasTipCap = big.NewInt(1000000000)
	auth.GasLimit = 21000

	balance := new(big.Int)
	balance.SetString("10000000000000000000", 10) // 10 eth in wei

	address := auth.From
	genesisAlloc := map[common.Address]core.GenesisAccount{
		address: {
			Balance: balance,
		},
	}

	blockGasLimit := uint64(4712388)
	client := backends.NewSimulatedBackend(genesisAlloc, blockGasLimit)

	toAddress := common.HexToAddress("0x4592d8f8d7b001e72cb26a73e4fa1806a51ac79d")
	// 直接用TransactOpts构造转账交易
	tx, err := bind.SendEther(auth, client, toAddress, big.NewInt(1000000000000000000), nil)
	if err != nil {
		t.Fatalf("failed to send transaction: %v", err)
	}

	t.Logf("tx sent: %s\n", tx.Hash().Hex())

	client.Commit()

	receipt, err := client.TransactionReceipt(context.Background(), tx.Hash())
	if err != nil {
		t.Fatalf("failed to get transaction receipt: %v", err)
	}
	if receipt == nil {
		t.Fatal("receipt is empty")
	}

	t.Logf("status: %v\n", receipt.Status) // status: 1
}

方式2：手动构造EIP1559类型交易 #

如果你需要手动构造交易，改用DynamicFeeTx类型即可，只需要替换原有交易构造部分的代码：

nonce, err := client.PendingNonceAt(context.Background(), fromAddress)
if err != nil {
	t.Fatalf("failed to get nonce: %v", err)
}

value := big.NewInt(1000000000000000000) // 1 eth
gasLimit := uint64(21000)
toAddress := common.HexToAddress("0x4592d8f8d7b001e72cb26a73e4fa1806a51ac79d")
// 构造EIP1559交易参数
tx := types.NewTx(&types.DynamicFeeTx{
	ChainID:   big.NewInt(1337),
	Nonce:     nonce,
	GasTipCap: big.NewInt(1000000000), // 优先级费
	GasFeeCap: big.NewInt(1000000000), // 最高付费，高于base fee即可
	Gas:       gasLimit,
	To:        &toAddress,
	Value:     value,
	Data:      nil,
})
// 签名使用LondonSigner即可
signedTx, err := types.SignTx(tx, types.NewLondonSigner(big.NewInt(1337)), privateKey)
if err != nil {
	t.Fatalf("failed to sign transaction: %v", err)
}

内容的提问来源于stack exchange，提问作者Arjan van Eersel