// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (governance/extensions/GovernorVotes.sol) pragma solidity ^0.8.20; import {Governor} from "../Governor.sol"; import {IVotes} from "../utils/IVotes.sol"; import {IERC5805} from "../../interfaces/IERC5805.sol"; import {SafeCast} from "../../utils/math/SafeCast.sol"; import {Time} from "../../utils/types/Time.sol"; /** * @dev Extension of {Governor} for voting weight extraction from an {ERC20Votes} token, or since v4.5 an {ERC721Votes} * token. */ abstract contract GovernorVotes is Governor { IERC5805 private immutable _token; constructor(IVotes tokenAddress) { _token = IERC5805(address(tokenAddress)); } /** * @dev The token that voting power is sourced from. */ function token() public view virtual returns (IERC5805) { return _token; } /** * @dev Clock (as specified in ERC-6372) is set to match the token's clock. Fallback to block numbers if the token * does not implement ERC-6372. */ function clock() public view virtual override returns (uint48) { try token().clock() returns (uint48 timepoint) { return timepoint; } catch { return Time.blockNumber(); } } /** * @dev Machine-readable description of the clock as specified in ERC-6372. */ // solhint-disable-next-line func-name-mixedcase function CLOCK_MODE() public view virtual override returns (string memory) { try token().CLOCK_MODE() returns (string memory clockmode) { return clockmode; } catch { return "mode=blocknumber&from=default"; } } /** * Read the voting weight from the token's built in snapshot mechanism (see {Governor-_getVotes}). */ function _getVotes( address account, uint256 timepoint, bytes memory /*params*/ ) internal view virtual override returns (uint256) { return token().getPastVotes(account, timepoint); } }