ERC20 extension for governance tokens (vote delegation and snapshots) (#2632)
Co-authored-by: Francisco Giordano <frangio.1@gmail.com>pull/2670/head
Hadrien Croubois
4 years ago
committed by
GitHub
parent
8669481309
commit
100ca0b8a2
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// SPDX-License-Identifier: MIT |
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pragma solidity ^0.8.0; |
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import "../token/ERC20/extensions/draft-ERC20Votes.sol"; |
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contract ERC20VotesMock is ERC20Votes { |
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constructor ( |
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string memory name, |
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string memory symbol, |
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address initialAccount, |
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uint256 initialBalance |
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) payable ERC20(name, symbol) ERC20Permit(name) { |
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_mint(initialAccount, initialBalance); |
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} |
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function getChainId() external view returns (uint256) { |
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return block.chainid; |
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} |
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} |
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// SPDX-License-Identifier: MIT |
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pragma solidity ^0.8.0; |
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import "./draft-ERC20Permit.sol"; |
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import "./draft-IERC20Votes.sol"; |
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import "../../../utils/math/Math.sol"; |
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import "../../../utils/math/SafeCast.sol"; |
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import "../../../utils/cryptography/ECDSA.sol"; |
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/** |
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* @dev Extension of the ERC20 token contract to support Compound's voting and delegation. |
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* |
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* This extensions keeps a history (checkpoints) of each account's vote power. Vote power can be delegated either |
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* by calling the {delegate} function directly, or by providing a signature to be used with {delegateBySig}. Voting |
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* power can be queried through the public accessors {getCurrentVotes} and {getPriorVotes}. |
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* |
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* By default, token balance does not account for voting power. This makes transfers cheaper. The downside is that it |
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* requires users to delegate to themselves in order to activate checkpoints and have their voting power tracked. |
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* Enabling self-delegation can easily be done by overriding the {delegates} function. Keep in mind however that this |
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* will significantly increase the base gas cost of transfers. |
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* |
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* _Available since v4.2._ |
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*/ |
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abstract contract ERC20Votes is IERC20Votes, ERC20Permit { |
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bytes32 private constant _DELEGATION_TYPEHASH = keccak256("Delegation(address delegatee,uint256 nonce,uint256 expiry)"); |
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mapping (address => address) private _delegates; |
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mapping (address => Checkpoint[]) private _checkpoints; |
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/** |
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* @dev Get the `pos`-th checkpoint for `account`. |
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*/ |
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function checkpoints(address account, uint32 pos) external view virtual override returns (Checkpoint memory) { |
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return _checkpoints[account][pos]; |
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} |
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/** |
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* @dev Get number of checkpoints for `account`. |
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*/ |
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function numCheckpoints(address account) external view virtual override returns (uint32) { |
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return SafeCast.toUint32(_checkpoints[account].length); |
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} |
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/** |
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* @dev Get the address `account` is currently delegating to. |
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*/ |
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function delegates(address account) public view virtual override returns (address) { |
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return _delegates[account]; |
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} |
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/** |
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* @dev Gets the current votes balance for `account` |
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*/ |
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function getCurrentVotes(address account) external view override returns (uint256) { |
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uint256 pos = _checkpoints[account].length; |
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return pos == 0 ? 0 : _checkpoints[account][pos - 1].votes; |
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} |
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/** |
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* @dev Determine the number of votes for `account` at the begining of `blockNumber`. |
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*/ |
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function getPriorVotes(address account, uint256 blockNumber) external view override returns (uint256) { |
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require(blockNumber < block.number, "ERC20Votes::getPriorVotes: not yet determined"); |
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Checkpoint[] storage ckpts = _checkpoints[account]; |
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// We run a binary search to look for the earliest checkpoint taken after `blockNumber`. |
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// |
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// During the loop, the index of the wanted checkpoint remains in the range [low, high). |
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// With each iteration, either `low` or `high` is moved towards the middle of the range to maintain the invariant. |
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// - If the middle checkpoint is after `blockNumber`, we look in [low, mid) |
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// - If the middle checkpoint is before `blockNumber`, we look in [mid+1, high) |
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// Once we reach a single value (when low == high), we've found the right checkpoint at the index high-1, if not |
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// out of bounds (in which case we're looking too far in the past and the result is 0). |
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// Note that if the latest checkpoint available is exactly for `blockNumber`, we end up with an index that is |
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// past the end of the array, so we technically don't find a checkpoint after `blockNumber`, but it works out |
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// the same. |
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uint256 high = ckpts.length; |
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uint256 low = 0; |
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while (low < high) { |
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uint256 mid = Math.average(low, high); |
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if (ckpts[mid].fromBlock > blockNumber) { |
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high = mid; |
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} else { |
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low = mid + 1; |
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} |
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} |
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return high == 0 ? 0 : ckpts[high - 1].votes; |
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} |
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/** |
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* @dev Delegate votes from the sender to `delegatee`. |
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*/ |
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function delegate(address delegatee) public virtual override { |
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return _delegate(_msgSender(), delegatee); |
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} |
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/** |
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* @dev Delegates votes from signer to `delegatee` |
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*/ |
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function delegateBySig(address delegatee, uint256 nonce, uint256 expiry, uint8 v, bytes32 r, bytes32 s) |
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public virtual override |
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{ |
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require(block.timestamp <= expiry, "ERC20Votes::delegateBySig: signature expired"); |
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address signer = ECDSA.recover( |
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_hashTypedDataV4(keccak256(abi.encode( |
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_DELEGATION_TYPEHASH, |
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delegatee, |
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nonce, |
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expiry |
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))), |
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v, r, s |
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); |
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require(nonce == _useNonce(signer), "ERC20Votes::delegateBySig: invalid nonce"); |
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return _delegate(signer, delegatee); |
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} |
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/** |
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* @dev Change delegation for `delegator` to `delegatee`. |
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*/ |
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function _delegate(address delegator, address delegatee) internal virtual { |
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address currentDelegate = delegates(delegator); |
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uint256 delegatorBalance = balanceOf(delegator); |
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_delegates[delegator] = delegatee; |
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emit DelegateChanged(delegator, currentDelegate, delegatee); |
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_moveVotingPower(currentDelegate, delegatee, delegatorBalance); |
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} |
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function _moveVotingPower(address src, address dst, uint256 amount) private { |
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if (src != dst && amount > 0) { |
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if (src != address(0)) { |
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uint256 srcCkptLen = _checkpoints[src].length; |
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uint256 srcCkptOld = srcCkptLen == 0 ? 0 : _checkpoints[src][srcCkptLen - 1].votes; |
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uint256 srcCkptNew = srcCkptOld - amount; |
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_writeCheckpoint(src, srcCkptLen, srcCkptOld, srcCkptNew); |
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} |
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if (dst != address(0)) { |
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uint256 dstCkptLen = _checkpoints[dst].length; |
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uint256 dstCkptOld = dstCkptLen == 0 ? 0 : _checkpoints[dst][dstCkptLen - 1].votes; |
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uint256 dstCkptNew = dstCkptOld + amount; |
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_writeCheckpoint(dst, dstCkptLen, dstCkptOld, dstCkptNew); |
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} |
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} |
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} |
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function _writeCheckpoint(address delegatee, uint256 pos, uint256 oldWeight, uint256 newWeight) private { |
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if (pos > 0 && _checkpoints[delegatee][pos - 1].fromBlock == block.number) { |
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_checkpoints[delegatee][pos - 1].votes = SafeCast.toUint224(newWeight); |
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} else { |
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_checkpoints[delegatee].push(Checkpoint({ |
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fromBlock: SafeCast.toUint32(block.number), |
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votes: SafeCast.toUint224(newWeight) |
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})); |
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} |
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emit DelegateVotesChanged(delegatee, oldWeight, newWeight); |
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} |
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function _mint(address account, uint256 amount) internal virtual override { |
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super._mint(account, amount); |
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require(totalSupply() <= type(uint224).max, "ERC20Votes: total supply exceeds 2**224"); |
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} |
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function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual override { |
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_moveVotingPower(delegates(from), delegates(to), amount); |
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} |
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} |
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@ -0,0 +1,23 @@ |
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// SPDX-License-Identifier: MIT |
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pragma solidity ^0.8.0; |
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import "../IERC20.sol"; |
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interface IERC20Votes is IERC20 { |
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struct Checkpoint { |
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uint32 fromBlock; |
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uint224 votes; |
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} |
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event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate); |
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event DelegateVotesChanged(address indexed delegate, uint256 previousBalance, uint256 newBalance); |
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function delegates(address owner) external view returns (address); |
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function checkpoints(address account, uint32 pos) external view returns (Checkpoint memory); |
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function numCheckpoints(address account) external view returns (uint32); |
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function getCurrentVotes(address account) external view returns (uint256); |
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function getPriorVotes(address account, uint256 blockNumber) external view returns (uint256); |
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function delegate(address delegatee) external; |
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function delegateBySig(address delegatee, uint nonce, uint expiry, uint8 v, bytes32 r, bytes32 s) external; |
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} |
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@ -0,0 +1,458 @@ |
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/* eslint-disable */ |
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const { BN, constants, expectEvent, expectRevert, time } = require('@openzeppelin/test-helpers'); |
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const { expect } = require('chai'); |
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const { MAX_UINT256, ZERO_ADDRESS, ZERO_BYTES32 } = constants; |
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const { fromRpcSig } = require('ethereumjs-util'); |
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const ethSigUtil = require('eth-sig-util'); |
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const Wallet = require('ethereumjs-wallet').default; |
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const { promisify } = require('util'); |
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const queue = promisify(setImmediate); |
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const ERC20VotesMock = artifacts.require('ERC20VotesMock'); |
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const { EIP712Domain, domainSeparator } = require('../../../helpers/eip712'); |
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const Delegation = [ |
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{ name: 'delegatee', type: 'address' }, |
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{ name: 'nonce', type: 'uint256' }, |
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{ name: 'expiry', type: 'uint256' }, |
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]; |
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async function countPendingTransactions() { |
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return parseInt( |
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await network.provider.send('eth_getBlockTransactionCountByNumber', ['pending']) |
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); |
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} |
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async function batchInBlock (txs) { |
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try { |
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// disable auto-mining
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await network.provider.send('evm_setAutomine', [false]); |
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// send all transactions
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const promises = txs.map(fn => fn()); |
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// wait for node to have all pending transactions
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while (txs.length > await countPendingTransactions()) { |
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await queue(); |
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} |
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// mine one block
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await network.provider.send('evm_mine'); |
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// fetch receipts
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const receipts = await Promise.all(promises); |
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// Sanity check, all tx should be in the same block
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const minedBlocks = new Set(receipts.map(({ receipt }) => receipt.blockNumber)); |
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expect(minedBlocks.size).to.equal(1); |
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return receipts; |
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} finally { |
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// enable auto-mining
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await network.provider.send('evm_setAutomine', [true]); |
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} |
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} |
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contract('ERC20Votes', function (accounts) { |
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const [ holder, recipient, holderDelegatee, recipientDelegatee, other1, other2 ] = accounts; |
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const name = 'My Token'; |
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const symbol = 'MTKN'; |
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const version = '1'; |
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const supply = new BN('10000000000000000000000000'); |
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beforeEach(async function () { |
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this.token = await ERC20VotesMock.new(name, symbol, holder, supply); |
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// We get the chain id from the contract because Ganache (used for coverage) does not return the same chain id
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// from within the EVM as from the JSON RPC interface.
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// See https://github.com/trufflesuite/ganache-core/issues/515
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this.chainId = await this.token.getChainId(); |
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}); |
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it('initial nonce is 0', async function () { |
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expect(await this.token.nonces(holder)).to.be.bignumber.equal('0'); |
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}); |
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it('domain separator', async function () { |
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expect( |
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await this.token.DOMAIN_SEPARATOR(), |
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).to.equal( |
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await domainSeparator(name, version, this.chainId, this.token.address), |
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); |
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}); |
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it('minting restriction', async function () { |
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const amount = new BN('2').pow(new BN('224')); |
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await expectRevert( |
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ERC20VotesMock.new(name, symbol, holder, amount), |
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'ERC20Votes: total supply exceeds 2**224', |
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); |
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}); |
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describe('set delegation', function () { |
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describe('call', function () { |
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it('delegation with balance', async function () { |
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expect(await this.token.delegates(holder)).to.be.equal(ZERO_ADDRESS); |
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const { receipt } = await this.token.delegate(holder, { from: holder }); |
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expectEvent(receipt, 'DelegateChanged', { |
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delegator: holder, |
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fromDelegate: ZERO_ADDRESS, |
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toDelegate: holder, |
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}); |
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expectEvent(receipt, 'DelegateVotesChanged', { |
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delegate: holder, |
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previousBalance: '0', |
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newBalance: supply, |
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}); |
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expect(await this.token.delegates(holder)).to.be.equal(holder); |
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expect(await this.token.getCurrentVotes(holder)).to.be.bignumber.equal(supply); |
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expect(await this.token.getPriorVotes(holder, receipt.blockNumber - 1)).to.be.bignumber.equal('0'); |
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await time.advanceBlock(); |
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expect(await this.token.getPriorVotes(holder, receipt.blockNumber)).to.be.bignumber.equal(supply); |
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}); |
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it('delegation without balance', async function () { |
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expect(await this.token.delegates(recipient)).to.be.equal(ZERO_ADDRESS); |
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const { receipt } = await this.token.delegate(recipient, { from: recipient }); |
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expectEvent(receipt, 'DelegateChanged', { |
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delegator: recipient, |
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fromDelegate: ZERO_ADDRESS, |
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toDelegate: recipient, |
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}); |
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expectEvent.notEmitted(receipt, 'DelegateVotesChanged'); |
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expect(await this.token.delegates(recipient)).to.be.equal(recipient); |
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}); |
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}); |
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describe('with signature', function () { |
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const delegator = Wallet.generate(); |
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const delegatorAddress = web3.utils.toChecksumAddress(delegator.getAddressString()); |
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const nonce = 0; |
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const buildData = (chainId, verifyingContract, message) => ({ data: { |
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primaryType: 'Delegation', |
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types: { EIP712Domain, Delegation }, |
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domain: { name, version, chainId, verifyingContract }, |
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message, |
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}}); |
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beforeEach(async function () { |
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await this.token.transfer(delegatorAddress, supply, { from: holder }); |
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}); |
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it('accept signed delegation', async function () { |
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const { v, r, s } = fromRpcSig(ethSigUtil.signTypedMessage( |
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delegator.getPrivateKey(), |
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buildData(this.chainId, this.token.address, { |
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delegatee: delegatorAddress, |
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nonce, |
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expiry: MAX_UINT256, |
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}), |
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)); |
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expect(await this.token.delegates(delegatorAddress)).to.be.equal(ZERO_ADDRESS); |
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const { receipt } = await this.token.delegateBySig(delegatorAddress, nonce, MAX_UINT256, v, r, s); |
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expectEvent(receipt, 'DelegateChanged', { |
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delegator: delegatorAddress, |
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fromDelegate: ZERO_ADDRESS, |
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toDelegate: delegatorAddress, |
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}); |
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expectEvent(receipt, 'DelegateVotesChanged', { |
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delegate: delegatorAddress, |
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previousBalance: '0', |
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newBalance: supply, |
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}); |
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expect(await this.token.delegates(delegatorAddress)).to.be.equal(delegatorAddress); |
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expect(await this.token.getCurrentVotes(delegatorAddress)).to.be.bignumber.equal(supply); |
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expect(await this.token.getPriorVotes(delegatorAddress, receipt.blockNumber - 1)).to.be.bignumber.equal('0'); |
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await time.advanceBlock(); |
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expect(await this.token.getPriorVotes(delegatorAddress, receipt.blockNumber)).to.be.bignumber.equal(supply); |
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}); |
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it('rejects reused signature', async function () { |
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const { v, r, s } = fromRpcSig(ethSigUtil.signTypedMessage( |
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delegator.getPrivateKey(), |
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buildData(this.chainId, this.token.address, { |
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delegatee: delegatorAddress, |
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nonce, |
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expiry: MAX_UINT256, |
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}), |
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)); |
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await this.token.delegateBySig(delegatorAddress, nonce, MAX_UINT256, v, r, s); |
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await expectRevert( |
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this.token.delegateBySig(delegatorAddress, nonce, MAX_UINT256, v, r, s), |
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'ERC20Votes::delegateBySig: invalid nonce', |
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); |
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}); |
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it('rejects bad delegatee', async function () { |
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const { v, r, s } = fromRpcSig(ethSigUtil.signTypedMessage( |
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delegator.getPrivateKey(), |
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buildData(this.chainId, this.token.address, { |
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delegatee: delegatorAddress, |
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nonce, |
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expiry: MAX_UINT256, |
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}), |
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)); |
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const { logs } = await this.token.delegateBySig(holderDelegatee, nonce, MAX_UINT256, v, r, s); |
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const { args } = logs.find(({ event }) => event == 'DelegateChanged'); |
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expect(args.delegator).to.not.be.equal(delegatorAddress); |
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expect(args.fromDelegate).to.be.equal(ZERO_ADDRESS); |
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expect(args.toDelegate).to.be.equal(holderDelegatee); |
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}); |
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it('rejects bad nonce', async function () { |
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const { v, r, s } = fromRpcSig(ethSigUtil.signTypedMessage( |
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delegator.getPrivateKey(), |
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buildData(this.chainId, this.token.address, { |
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delegatee: delegatorAddress, |
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nonce, |
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expiry: MAX_UINT256, |
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}), |
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)); |
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await expectRevert( |
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this.token.delegateBySig(delegatorAddress, nonce + 1, MAX_UINT256, v, r, s), |
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'ERC20Votes::delegateBySig: invalid nonce', |
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); |
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}); |
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it('rejects expired permit', async function () { |
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const expiry = (await time.latest()) - time.duration.weeks(1); |
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const { v, r, s } = fromRpcSig(ethSigUtil.signTypedMessage( |
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delegator.getPrivateKey(), |
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buildData(this.chainId, this.token.address, { |
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delegatee: delegatorAddress, |
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nonce, |
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expiry, |
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}), |
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)); |
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|
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await expectRevert( |
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this.token.delegateBySig(delegatorAddress, nonce, expiry, v, r, s), |
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'ERC20Votes::delegateBySig: signature expired', |
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); |
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}); |
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}); |
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}); |
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describe('change delegation', function () { |
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beforeEach(async function () { |
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await this.token.delegate(holder, { from: holder }); |
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}); |
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it('call', async function () { |
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expect(await this.token.delegates(holder)).to.be.equal(holder); |
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const { receipt } = await this.token.delegate(holderDelegatee, { from: holder }); |
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expectEvent(receipt, 'DelegateChanged', { |
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delegator: holder, |
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fromDelegate: holder, |
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toDelegate: holderDelegatee, |
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}); |
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expectEvent(receipt, 'DelegateVotesChanged', { |
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delegate: holder, |
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previousBalance: supply, |
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newBalance: '0', |
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}); |
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expectEvent(receipt, 'DelegateVotesChanged', { |
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delegate: holderDelegatee, |
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previousBalance: '0', |
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newBalance: supply, |
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}); |
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|
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expect(await this.token.delegates(holder)).to.be.equal(holderDelegatee); |
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expect(await this.token.getCurrentVotes(holder)).to.be.bignumber.equal('0'); |
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expect(await this.token.getCurrentVotes(holderDelegatee)).to.be.bignumber.equal(supply); |
||||
expect(await this.token.getPriorVotes(holder, receipt.blockNumber - 1)).to.be.bignumber.equal(supply); |
||||
expect(await this.token.getPriorVotes(holderDelegatee, receipt.blockNumber - 1)).to.be.bignumber.equal('0'); |
||||
await time.advanceBlock(); |
||||
expect(await this.token.getPriorVotes(holder, receipt.blockNumber)).to.be.bignumber.equal('0'); |
||||
expect(await this.token.getPriorVotes(holderDelegatee, receipt.blockNumber)).to.be.bignumber.equal(supply); |
||||
}); |
||||
}); |
||||
|
||||
describe('transfers', function () { |
||||
it('no delegation', async function () { |
||||
const { receipt } = await this.token.transfer(recipient, 1, { from: holder }); |
||||
expectEvent(receipt, 'Transfer', { from: holder, to: recipient, value: '1' }); |
||||
expectEvent.notEmitted(receipt, 'DelegateVotesChanged'); |
||||
|
||||
this.holderVotes = '0'; |
||||
this.recipientVotes = '0'; |
||||
}); |
||||
|
||||
it('sender delegation', async function () { |
||||
await this.token.delegate(holder, { from: holder }); |
||||
|
||||
const { receipt } = await this.token.transfer(recipient, 1, { from: holder }); |
||||
expectEvent(receipt, 'Transfer', { from: holder, to: recipient, value: '1' }); |
||||
expectEvent(receipt, 'DelegateVotesChanged', { delegate: holder, previousBalance: supply, newBalance: supply.subn(1) }); |
||||
|
||||
this.holderVotes = supply.subn(1); |
||||
this.recipientVotes = '0'; |
||||
}); |
||||
|
||||
it('receiver delegation', async function () { |
||||
await this.token.delegate(recipient, { from: recipient }); |
||||
|
||||
const { receipt } = await this.token.transfer(recipient, 1, { from: holder }); |
||||
expectEvent(receipt, 'Transfer', { from: holder, to: recipient, value: '1' }); |
||||
expectEvent(receipt, 'DelegateVotesChanged', { delegate: recipient, previousBalance: '0', newBalance: '1' }); |
||||
|
||||
this.holderVotes = '0'; |
||||
this.recipientVotes = '1'; |
||||
}); |
||||
|
||||
it('full delegation', async function () { |
||||
await this.token.delegate(holder, { from: holder }); |
||||
await this.token.delegate(recipient, { from: recipient }); |
||||
|
||||
const { receipt } = await this.token.transfer(recipient, 1, { from: holder }); |
||||
expectEvent(receipt, 'Transfer', { from: holder, to: recipient, value: '1' }); |
||||
expectEvent(receipt, 'DelegateVotesChanged', { delegate: holder, previousBalance: supply, newBalance: supply.subn(1) }); |
||||
expectEvent(receipt, 'DelegateVotesChanged', { delegate: recipient, previousBalance: '0', newBalance: '1' }); |
||||
|
||||
this.holderVotes = supply.subn(1); |
||||
this.recipientVotes = '1'; |
||||
}); |
||||
|
||||
afterEach(async function () { |
||||
expect(await this.token.getCurrentVotes(holder)).to.be.bignumber.equal(this.holderVotes); |
||||
expect(await this.token.getCurrentVotes(recipient)).to.be.bignumber.equal(this.recipientVotes); |
||||
|
||||
// need to advance 2 blocks to see the effect of a transfer on "getPriorVotes"
|
||||
const blockNumber = await time.latestBlock(); |
||||
await time.advanceBlock(); |
||||
expect(await this.token.getPriorVotes(holder, blockNumber)).to.be.bignumber.equal(this.holderVotes); |
||||
expect(await this.token.getPriorVotes(recipient, blockNumber)).to.be.bignumber.equal(this.recipientVotes); |
||||
}); |
||||
}); |
||||
|
||||
// The following tests are a adaptation of https://github.com/compound-finance/compound-protocol/blob/master/tests/Governance/CompTest.js.
|
||||
describe('Compound test suite', function () { |
||||
describe('balanceOf', function () { |
||||
it('grants to initial account', async function () { |
||||
expect(await this.token.balanceOf(holder)).to.be.bignumber.equal('10000000000000000000000000'); |
||||
}); |
||||
}); |
||||
|
||||
describe('numCheckpoints', function () { |
||||
it('returns the number of checkpoints for a delegate', async function () { |
||||
await this.token.transfer(recipient, '100', { from: holder }); //give an account a few tokens for readability
|
||||
expect(await this.token.numCheckpoints(other1)).to.be.bignumber.equal('0'); |
||||
|
||||
const t1 = await this.token.delegate(other1, { from: recipient }); |
||||
expect(await this.token.numCheckpoints(other1)).to.be.bignumber.equal('1'); |
||||
|
||||
const t2 = await this.token.transfer(other2, 10, { from: recipient }); |
||||
expect(await this.token.numCheckpoints(other1)).to.be.bignumber.equal('2'); |
||||
|
||||
const t3 = await this.token.transfer(other2, 10, { from: recipient }); |
||||
expect(await this.token.numCheckpoints(other1)).to.be.bignumber.equal('3'); |
||||
|
||||
const t4 = await this.token.transfer(recipient, 20, { from: holder }); |
||||
expect(await this.token.numCheckpoints(other1)).to.be.bignumber.equal('4'); |
||||
|
||||
expect(await this.token.checkpoints(other1, 0)).to.be.deep.equal([ t1.receipt.blockNumber.toString(), '100' ]); |
||||
expect(await this.token.checkpoints(other1, 1)).to.be.deep.equal([ t2.receipt.blockNumber.toString(), '90' ]); |
||||
expect(await this.token.checkpoints(other1, 2)).to.be.deep.equal([ t3.receipt.blockNumber.toString(), '80' ]); |
||||
expect(await this.token.checkpoints(other1, 3)).to.be.deep.equal([ t4.receipt.blockNumber.toString(), '100' ]); |
||||
|
||||
await time.advanceBlock(); |
||||
expect(await this.token.getPriorVotes(other1, t1.receipt.blockNumber)).to.be.bignumber.equal('100'); |
||||
expect(await this.token.getPriorVotes(other1, t2.receipt.blockNumber)).to.be.bignumber.equal('90'); |
||||
expect(await this.token.getPriorVotes(other1, t3.receipt.blockNumber)).to.be.bignumber.equal('80'); |
||||
expect(await this.token.getPriorVotes(other1, t4.receipt.blockNumber)).to.be.bignumber.equal('100'); |
||||
}); |
||||
|
||||
it('does not add more than one checkpoint in a block', async function () { |
||||
await this.token.transfer(recipient, '100', { from: holder }); |
||||
expect(await this.token.numCheckpoints(other1)).to.be.bignumber.equal('0'); |
||||
|
||||
const [ t1, t2, t3 ] = await batchInBlock([ |
||||
() => this.token.delegate(other1, { from: recipient, gas: 100000 }), |
||||
() => this.token.transfer(other2, 10, { from: recipient, gas: 100000 }), |
||||
() => this.token.transfer(other2, 10, { from: recipient, gas: 100000 }), |
||||
]); |
||||
expect(await this.token.numCheckpoints(other1)).to.be.bignumber.equal('1'); |
||||
expect(await this.token.checkpoints(other1, 0)).to.be.deep.equal([ t1.receipt.blockNumber.toString(), '80' ]); |
||||
// expectReve(await this.token.checkpoints(other1, 1)).to.be.deep.equal([ '0', '0' ]); // Reverts due to array overflow check
|
||||
// expect(await this.token.checkpoints(other1, 2)).to.be.deep.equal([ '0', '0' ]); // Reverts due to array overflow check
|
||||
|
||||
const t4 = await this.token.transfer(recipient, 20, { from: holder }); |
||||
expect(await this.token.numCheckpoints(other1)).to.be.bignumber.equal('2'); |
||||
expect(await this.token.checkpoints(other1, 1)).to.be.deep.equal([ t4.receipt.blockNumber.toString(), '100' ]); |
||||
}); |
||||
}); |
||||
|
||||
describe('getPriorVotes', function () { |
||||
it('reverts if block number >= current block', async function () { |
||||
await expectRevert( |
||||
this.token.getPriorVotes(other1, 5e10), |
||||
'ERC20Votes::getPriorVotes: not yet determined', |
||||
); |
||||
}); |
||||
|
||||
it('returns 0 if there are no checkpoints', async function () { |
||||
expect(await this.token.getPriorVotes(other1, 0)).to.be.bignumber.equal('0'); |
||||
}); |
||||
|
||||
it('returns the latest block if >= last checkpoint block', async function () { |
||||
const t1 = await this.token.delegate(other1, { from: holder }); |
||||
await time.advanceBlock(); |
||||
await time.advanceBlock(); |
||||
|
||||
expect(await this.token.getPriorVotes(other1, t1.receipt.blockNumber)).to.be.bignumber.equal('10000000000000000000000000'); |
||||
expect(await this.token.getPriorVotes(other1, t1.receipt.blockNumber + 1)).to.be.bignumber.equal('10000000000000000000000000'); |
||||
}); |
||||
|
||||
it('returns zero if < first checkpoint block', async function () { |
||||
await time.advanceBlock(); |
||||
const t1 = await this.token.delegate(other1, { from: holder }); |
||||
await time.advanceBlock(); |
||||
await time.advanceBlock(); |
||||
|
||||
expect(await this.token.getPriorVotes(other1, t1.receipt.blockNumber - 1)).to.be.bignumber.equal('0'); |
||||
expect(await this.token.getPriorVotes(other1, t1.receipt.blockNumber + 1)).to.be.bignumber.equal('10000000000000000000000000'); |
||||
}); |
||||
|
||||
it('generally returns the voting balance at the appropriate checkpoint', async function () { |
||||
const t1 = await this.token.delegate(other1, { from: holder }); |
||||
await time.advanceBlock(); |
||||
await time.advanceBlock(); |
||||
const t2 = await this.token.transfer(other2, 10, { from: holder }); |
||||
await time.advanceBlock(); |
||||
await time.advanceBlock(); |
||||
const t3 = await this.token.transfer(other2, 10, { from: holder }); |
||||
await time.advanceBlock(); |
||||
await time.advanceBlock(); |
||||
const t4 = await this.token.transfer(holder, 20, { from: other2 }); |
||||
await time.advanceBlock(); |
||||
await time.advanceBlock(); |
||||
|
||||
expect(await this.token.getPriorVotes(other1, t1.receipt.blockNumber - 1)).to.be.bignumber.equal('0'); |
||||
expect(await this.token.getPriorVotes(other1, t1.receipt.blockNumber)).to.be.bignumber.equal('10000000000000000000000000'); |
||||
expect(await this.token.getPriorVotes(other1, t1.receipt.blockNumber + 1)).to.be.bignumber.equal('10000000000000000000000000'); |
||||
expect(await this.token.getPriorVotes(other1, t2.receipt.blockNumber)).to.be.bignumber.equal('9999999999999999999999990'); |
||||
expect(await this.token.getPriorVotes(other1, t2.receipt.blockNumber + 1)).to.be.bignumber.equal('9999999999999999999999990'); |
||||
expect(await this.token.getPriorVotes(other1, t3.receipt.blockNumber)).to.be.bignumber.equal('9999999999999999999999980'); |
||||
expect(await this.token.getPriorVotes(other1, t3.receipt.blockNumber + 1)).to.be.bignumber.equal('9999999999999999999999980'); |
||||
expect(await this.token.getPriorVotes(other1, t4.receipt.blockNumber)).to.be.bignumber.equal('10000000000000000000000000'); |
||||
expect(await this.token.getPriorVotes(other1, t4.receipt.blockNumber + 1)).to.be.bignumber.equal('10000000000000000000000000'); |
||||
}); |
||||
}); |
||||
}); |
||||
}); |
||||
Loading…
Reference in new issue