Contract Source Code:
<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>
// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;
import {IERC20Deployer} from "./interfaces/IERC20Deployer.sol";
/// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
/// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
contract ERC20 {
/*//////////////////////////////////////////////////////////////
EVENTS
//////////////////////////////////////////////////////////////*/
event Transfer(address indexed from, address indexed to, uint256 amount);
event Approval(address indexed owner, address indexed spender, uint256 amount);
/*//////////////////////////////////////////////////////////////
METADATA STORAGE
//////////////////////////////////////////////////////////////*/
string public name;
string public symbol;
uint8 public immutable decimals;
address public curve;
address public pool;
error OnlyCurve();
error CurveNotCompleted();
/*//////////////////////////////////////////////////////////////
ERC20 STORAGE
//////////////////////////////////////////////////////////////*/
uint256 public totalSupply;
mapping(address => uint256) public balanceOf;
mapping(address => mapping(address => uint256)) public allowance;
/*//////////////////////////////////////////////////////////////
EIP-2612 STORAGE
//////////////////////////////////////////////////////////////*/
uint256 internal immutable INITIAL_CHAIN_ID;
bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;
mapping(address => uint256) public nonces;
/*//////////////////////////////////////////////////////////////
CONSTRUCTOR
//////////////////////////////////////////////////////////////*/
constructor() {
address sender = msg.sender;
(string memory _name, string memory _symbol, address _pool) = IERC20Deployer(sender).parameters();
decimals = 6;
name = _name;
symbol = _symbol;
pool = _pool;
curve = sender;
_mint(sender, 1_000_000_000 * 10 ** 6);
INITIAL_CHAIN_ID = block.chainid;
INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
}
/*//////////////////////////////////////////////////////////////
ERC20 CURVE LOGIC
//////////////////////////////////////////////////////////////*/
function completeBondingCurve() external {
if (msg.sender != curve) {
revert OnlyCurve();
}
curve = address(0);
}
/*//////////////////////////////////////////////////////////////
ERC20 LOGIC
//////////////////////////////////////////////////////////////*/
function approve(address spender, uint256 amount) public virtual returns (bool) {
allowance[msg.sender][spender] = amount;
emit Approval(msg.sender, spender, amount);
return true;
}
function transfer(address to, uint256 amount) public virtual returns (bool) {
_transfer(msg.sender, to, amount);
return true;
}
function transferFrom(address from, address to, uint256 amount) public virtual returns (bool) {
uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.
if (allowed != type(uint256).max) {
allowance[from][msg.sender] = allowed - amount;
}
_transfer(from, to, amount);
return true;
}
function burn(uint256 value) public virtual {
_burn(msg.sender, value);
}
/*//////////////////////////////////////////////////////////////
EIP-2612 LOGIC
//////////////////////////////////////////////////////////////*/
function permit(address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s)
public
virtual
{
require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");
// Unchecked because the only math done is incrementing
// the owner's nonce which cannot realistically overflow.
unchecked {
address recoveredAddress = ecrecover(
keccak256(
abi.encodePacked(
"\x19\x01",
DOMAIN_SEPARATOR(),
keccak256(
abi.encode(
keccak256(
"Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
),
owner,
spender,
value,
nonces[owner]++,
deadline
)
)
)
),
v,
r,
s
);
require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");
allowance[recoveredAddress][spender] = value;
}
emit Approval(owner, spender, value);
}
function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
}
function computeDomainSeparator() internal view virtual returns (bytes32) {
return keccak256(
abi.encode(
keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
keccak256(bytes(name)),
keccak256("1"),
block.chainid,
address(this)
)
);
}
/*//////////////////////////////////////////////////////////////
INTERNAL MINT/BURN/TRANSFER LOGIC
//////////////////////////////////////////////////////////////*/
function _mint(address to, uint256 amount) internal virtual {
totalSupply += amount;
// Cannot overflow because the sum of all user
// balances can't exceed the max uint256 value.
unchecked {
balanceOf[to] += amount;
}
emit Transfer(address(0), to, amount);
}
function _burn(address from, uint256 amount) internal virtual {
balanceOf[from] -= amount;
// Cannot underflow because a user's balance
// will never be larger than the total supply.
unchecked {
totalSupply -= amount;
}
emit Transfer(from, address(0), amount);
}
function _transfer(address from, address to, uint256 amount) internal virtual {
if ((curve != address(0)) && (from == pool || to == pool)) {
revert CurveNotCompleted();
}
// low level internal function
balanceOf[from] -= amount;
// Cannot overflow because the sum of all user
// balances can't exceed the max uint256 value.
unchecked {
balanceOf[to] += amount;
}
emit Transfer(from, to, amount);
}
}
<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.8.0;
interface IERC20Deployer {
function parameters() external returns (string memory name, string memory symbol, address pool);
}