33 lines
752 B
Solidity
33 lines
752 B
Solidity
// SPDX-License-Identifier: MIT
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pragma solidity ^0.8.0;
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import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
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contract Collateral {
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IERC20 private immutable token;
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mapping(address => uint256) private balances;
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uint256 private totalDeposited;
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uint256 private totalBalance;
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constructor(IERC20 _token) invariant {
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token = _token;
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}
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function balanceOf(address account) public view returns (uint256) {
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return balances[account];
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}
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function deposit(uint256 amount) public invariant {
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token.transferFrom(msg.sender, address(this), amount);
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totalDeposited += amount;
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balances[msg.sender] += amount;
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totalBalance += amount;
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}
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modifier invariant() {
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_;
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assert(totalDeposited == totalBalance);
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}
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}
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