// SPDX-License-Identifier: MIT pragma solidity 0.8.17; import {TokenNotContract} from "./Errors.sol"; import {SafeERC20, IERC20} from "@openzeppelin/contracts-4.5.0/token/ERC20/utils/SafeERC20.sol"; library UniversalTokenLib { using SafeERC20 for IERC20; address internal constant ETH_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE; /// @notice Transfers tokens to the given account. Reverts if transfer is not successful. /// @dev This might trigger fallback, if ETH is transferred to the contract. /// Make sure this can not lead to reentrancy attacks. function universalTransfer( address token, address to, uint256 value ) internal { // Don't do anything, if need to send tokens to this address if (to == address(this)) return; if (token == ETH_ADDRESS) { /// @dev Note: this can potentially lead to executing code in `to`. // solhint-disable-next-line avoid-low-level-calls (bool success, ) = to.call{value: value}(""); require(success, "ETH transfer failed"); } else { IERC20(token).safeTransfer(to, value); } } /// @notice Issues an infinite allowance to the spender, if the current allowance is insufficient /// to spend the given amount. function universalApproveInfinity( address token, address spender, uint256 amountToSpend ) internal { // ETH Chad doesn't require your approval if (token == ETH_ADDRESS) return; // No-op if allowance is already sufficient uint256 allowance = IERC20(token).allowance(address(this), spender); if (allowance >= amountToSpend) return; // Otherwise, reset approval to 0 and set to max allowance if (allowance > 0) IERC20(token).safeApprove(spender, 0); IERC20(token).safeApprove(spender, type(uint256).max); } /// @notice Returns the balance of the given token (or native ETH) for the given account. function universalBalanceOf(address token, address account) internal view returns (uint256) { if (token == ETH_ADDRESS) { return account.balance; } else { return IERC20(token).balanceOf(account); } } /// @dev Checks that token is a contract and not ETH_ADDRESS. function assertIsContract(address token) internal view { // Check that ETH_ADDRESS was not used (in case this is a predeploy on any of the chains) if (token == UniversalTokenLib.ETH_ADDRESS) revert TokenNotContract(); // Check that token is not an EOA if (token.code.length == 0) revert TokenNotContract(); } }