feat: add transaction builders and vm.executeTransaction binding

src/StdVm.sol

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.13;
+
+/// @title Minimal Vm interface for RLP encoding.
+interface VmRlp {
+    /// @notice RLP encodes a list of byte strings into an RLP list payload.
+    function toRlp(bytes[] calldata data) external pure returns (bytes memory);
+}
+
+/// @title Minimal Vm interface for transaction execution.
+interface VmExecuteTransaction {
+    /// @notice Executes an RLP-encoded transaction with full EVM semantics.
+    /// @dev Decodes using TempoTxEnvelope::decode() which auto-detects tx type.
+    /// @param rawTx The RLP-encoded transaction bytes.
+    /// @return The execution output bytes.
+    function executeTransaction(bytes calldata rawTx) external returns (bytes memory);
+}

src/tx/AccessListTypes.sol

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+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.13;
+
+/// @notice An entry in an EIP-2930 access list.
+struct AccessListItem {
+    address target;
+    bytes32[] storageKeys;
+}

src/tx/Eip1559TransactionLib.sol

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+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.13;
+
+import {VmRlp} from "../StdVm.sol";
+import {TxRlp} from "./TxRlp.sol";
+import {AccessListItem} from "./AccessListTypes.sol";
+
+/// @notice An EIP-1559 (type 2) Ethereum transaction.
+struct Eip1559Transaction {
+    uint64 chainId;
+    uint64 nonce;
+    uint256 maxPriorityFeePerGas;
+    uint256 maxFeePerGas;
+    uint64 gasLimit;
+    address to;
+    uint256 value;
+    bytes data;
+    AccessListItem[] accessList;
+}
+
+/// @title Builder and RLP encoder for EIP-1559 transactions (type 0x02).
+library Eip1559TransactionLib {
+    using Eip1559TransactionLib for Eip1559Transaction;
+
+    /// @notice EIP-1559 transaction type prefix.
+    uint8 internal constant TX_TYPE = 0x02;
+
+    /// @notice Creates a new EIP-1559 transaction with default values.
+    function create() internal view returns (Eip1559Transaction memory tx_) {
+        tx_.chainId = uint64(block.chainid);
+        tx_.gasLimit = 21000;
+    }
+
+    /// @notice Sets the chain ID.
+    function withChainId(Eip1559Transaction memory self, uint64 chainId)
+        internal
+        pure
+        returns (Eip1559Transaction memory)
+    {
+        self.chainId = chainId;
+        return self;
+    }
+
+    /// @notice Sets the nonce.
+    function withNonce(Eip1559Transaction memory self, uint64 nonce) internal pure returns (Eip1559Transaction memory) {
+        self.nonce = nonce;
+        return self;
+    }
+
+    /// @notice Sets the max priority fee per gas.
+    function withMaxPriorityFeePerGas(Eip1559Transaction memory self, uint256 fee)
+        internal
+        pure
+        returns (Eip1559Transaction memory)
+    {
+        self.maxPriorityFeePerGas = fee;
+        return self;
+    }
+
+    /// @notice Sets the max fee per gas.
+    function withMaxFeePerGas(Eip1559Transaction memory self, uint256 fee)
+        internal
+        pure
+        returns (Eip1559Transaction memory)
+    {
+        self.maxFeePerGas = fee;
+        return self;
+    }
+
+    /// @notice Sets the gas limit.
+    function withGasLimit(Eip1559Transaction memory self, uint64 gasLimit)
+        internal
+        pure
+        returns (Eip1559Transaction memory)
+    {
+        self.gasLimit = gasLimit;
+        return self;
+    }
+
+    /// @notice Sets the recipient address.
+    function withTo(Eip1559Transaction memory self, address to) internal pure returns (Eip1559Transaction memory) {
+        self.to = to;
+        return self;
+    }
+
+    /// @notice Sets the value to send.
+    function withValue(Eip1559Transaction memory self, uint256 value)
+        internal
+        pure
+        returns (Eip1559Transaction memory)
+    {
+        self.value = value;
+        return self;
+    }
+
+    /// @notice Sets the calldata.
+    function withData(Eip1559Transaction memory self, bytes memory data)
+        internal
+        pure
+        returns (Eip1559Transaction memory)
+    {
+        self.data = data;
+        return self;
+    }
+
+    /// @notice Sets the access list.
+    function withAccessList(Eip1559Transaction memory self, AccessListItem[] memory accessList)
+        internal
+        pure
+        returns (Eip1559Transaction memory)
+    {
+        self.accessList = accessList;
+        return self;
+    }
+
+    /// @notice RLP encodes the unsigned transaction with type prefix 0x02.
+    /// @dev Format: 0x02 || RLP([chainId, nonce, maxPriorityFeePerGas, maxFeePerGas, gasLimit, to, value, data, accessList])
+    function encode(Eip1559Transaction memory self, VmRlp) internal pure returns (bytes memory) {
+        bytes[] memory fields = new bytes[](9);
+
+        fields[0] = TxRlp.encodeString(TxRlp.encodeUint(self.chainId));
+        fields[1] = TxRlp.encodeString(TxRlp.encodeUint(self.nonce));
+        fields[2] = TxRlp.encodeString(TxRlp.encodeUint(self.maxPriorityFeePerGas));
+        fields[3] = TxRlp.encodeString(TxRlp.encodeUint(self.maxFeePerGas));
+        fields[4] = TxRlp.encodeString(TxRlp.encodeUint(self.gasLimit));
+        fields[5] = TxRlp.encodeString(self.to == address(0) ? TxRlp.encodeNone() : TxRlp.encodeAddress(self.to));
+        fields[6] = TxRlp.encodeString(TxRlp.encodeUint(self.value));
+        fields[7] = TxRlp.encodeString(self.data);
+        fields[8] = _encodeAccessList(self.accessList);
+
+        bytes memory rlpPayload = TxRlp.encodeRawList(fields);
+        return abi.encodePacked(TX_TYPE, rlpPayload);
+    }
+
+    /// @notice RLP encodes the signed transaction with type prefix 0x02.
+    /// @dev Format: 0x02 || RLP([chainId, nonce, maxPriorityFeePerGas, maxFeePerGas, gasLimit, to, value, data, accessList, yParity, r, s])
+    function encodeWithSignature(Eip1559Transaction memory self, VmRlp, uint8 v, bytes32 r, bytes32 s)
+        internal
+        pure
+        returns (bytes memory)
+    {
+        bytes[] memory fields = new bytes[](12);
+
+        fields[0] = TxRlp.encodeString(TxRlp.encodeUint(self.chainId));
+        fields[1] = TxRlp.encodeString(TxRlp.encodeUint(self.nonce));
+        fields[2] = TxRlp.encodeString(TxRlp.encodeUint(self.maxPriorityFeePerGas));
+        fields[3] = TxRlp.encodeString(TxRlp.encodeUint(self.maxFeePerGas));
+        fields[4] = TxRlp.encodeString(TxRlp.encodeUint(self.gasLimit));
+        fields[5] = TxRlp.encodeString(self.to == address(0) ? TxRlp.encodeNone() : TxRlp.encodeAddress(self.to));
+        fields[6] = TxRlp.encodeString(TxRlp.encodeUint(self.value));
+        fields[7] = TxRlp.encodeString(self.data);
+        fields[8] = _encodeAccessList(self.accessList);
+
+        // yParity: 0 or 1 (v - 27)
+        uint8 yParity = v >= 27 ? v - 27 : v;
+        fields[9] = TxRlp.encodeString(TxRlp.encodeUint(yParity));
+        fields[10] = TxRlp.encodeString(TxRlp.encodeBytes32(r));
+        fields[11] = TxRlp.encodeString(TxRlp.encodeBytes32(s));
+
+        bytes memory rlpPayload = TxRlp.encodeRawList(fields);
+        return abi.encodePacked(TX_TYPE, rlpPayload);
+    }
+
+    /// @notice Encodes the access list as an RLP list.
+    function _encodeAccessList(AccessListItem[] memory list) private pure returns (bytes memory) {
+        bytes[] memory encodedItems = new bytes[](list.length);
+        for (uint256 i = 0; i < list.length; i++) {
+            bytes[] memory keys = new bytes[](list[i].storageKeys.length);
+            for (uint256 j = 0; j < list[i].storageKeys.length; j++) {
+                keys[j] = TxRlp.encodeString(TxRlp.encodeBytes32Full(list[i].storageKeys[j]));
+            }
+            bytes memory keysList = TxRlp.encodeRawList(keys);
+
+            bytes[] memory itemFields = new bytes[](2);
+            itemFields[0] = TxRlp.encodeString(TxRlp.encodeAddress(list[i].target));
+            itemFields[1] = keysList;
+            encodedItems[i] = TxRlp.encodeRawList(itemFields);
+        }
+        return TxRlp.encodeRawList(encodedItems);
+    }
+}