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使用Create2预先计算合约地址

可以在部署合约之前预先计算合约地址,使用create2

Contract address can be precomputed, before the contract is deployed, using create2

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

contract Factory {
// Returns the address of the newly deployed contract
function deploy(
address _owner,
uint _foo,
bytes32 _salt
) public payable returns (address) {
// This syntax is a newer way to invoke create2 without assembly, you just need to pass salt
// https://docs.soliditylang.org/en/latest/control-structures.html#salted-contract-creations-create2
return address(new TestContract{salt: _salt}(_owner, _foo));
}
}

// This is the older way of doing it using assembly
contract FactoryAssembly {
event Deployed(address addr, uint salt);

// 1. Get bytecode of contract to be deployed
// NOTE: _owner and _foo are arguments of the TestContract's constructor
function getBytecode(address _owner, uint _foo) public pure returns (bytes memory) {
bytes memory bytecode = type(TestContract).creationCode;

return abi.encodePacked(bytecode, abi.encode(_owner, _foo));
}

// 2. Compute the address of the contract to be deployed
// NOTE: _salt is a random number used to create an address
function getAddress(
bytes memory bytecode,
uint _salt
) public view returns (address) {
bytes32 hash = keccak256(
abi.encodePacked(bytes1(0xff), address(this), _salt, keccak256(bytecode))
);

// NOTE: cast last 20 bytes of hash to address
return address(uint160(uint(hash)));
}

// 3. Deploy the contract
// NOTE:
// Check the event log Deployed which contains the address of the deployed TestContract.
// The address in the log should equal the address computed from above.
function deploy(bytes memory bytecode, uint _salt) public payable {
address addr;

/*
NOTE: How to call create2

create2(v, p, n, s)
create new contract with code at memory p to p + n
and send v wei
and return the new address
where new address = first 20 bytes of keccak256(0xff + address(this) + s + keccak256(mem[p…(p+n)))
s = big-endian 256-bit value
*/
assembly {
addr := create2(
callvalue(), // wei sent with current call
// Actual code starts after skipping the first 32 bytes
add(bytecode, 0x20),
mload(bytecode), // Load the size of code contained in the first 32 bytes
_salt // Salt from function arguments
)

if iszero(extcodesize(addr)) {
revert(0, 0)
}
}

emit Deployed(addr, _salt);
}
}

contract TestContract {
address public owner;
uint public foo;

constructor(address _owner, uint _foo) payable {
owner = _owner;
foo = _foo;
}

function getBalance() public view returns (uint) {
return address(this).balance;
}
}