Merge pull request #189 from DistributedCollective/development_bzx_co…

…mpare

Development bzx compare

.gitignore

@@ -3,6 +3,7 @@ __pycache__
 .DS_Store
 .history
 .hypothesis/
+.gradle/
 build/
 reports/
 node_modules/
@@ -26,4 +27,7 @@ solc-select
 .env
 node_modules
 artifacts/
-cache/
+cache/
+contracts_bzx/
+tmp/
+tmp

contracts/connectors/loantoken/AdvancedToken.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 
@@ -41,13 +41,12 @@ contract AdvancedToken is AdvancedTokenStorage {
 		uint256 _assetAmount,
 		uint256 _price
 	) internal returns (uint256) {
-		require(_tokenAmount <= balances[_who], "16");
-		// no need to require value <= totalSupply, since that would imply the
-		// sender's balance is greater than the totalSupply, which *should* be an assertion failure
+		//bzx compare
+		//TODO: Unit test
+		uint256 _balance = balances[_who].sub(_tokenAmount, "16");
 
-		uint256 _balance = balances[_who].sub(_tokenAmount);
+		// a rounding error may leave dust behind, so we clear this out
 		if (_balance <= 10) {
-			// we can't leave such small balance quantities
 			_tokenAmount = _tokenAmount.add(_balance);
 			_balance = 0;
 		}
@@ -57,7 +56,6 @@ contract AdvancedToken is AdvancedTokenStorage {
 
 		emit Burn(_who, _tokenAmount, _assetAmount, _price);
 		emit Transfer(_who, address(0), _tokenAmount);
-
 		return _balance;
 	}
 }

contracts/connectors/loantoken/AdvancedTokenStorage.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 
@@ -10,18 +10,16 @@ import "./LoanTokenBase.sol";
 contract AdvancedTokenStorage is LoanTokenBase {
 	using SafeMath for uint256;
 
-	// topic: 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef
 	event Transfer(address indexed from, address indexed to, uint256 value);
 
-	// topic: 0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925
 	event Approval(address indexed owner, address indexed spender, uint256 value);
 
-	// topic: 0xb4c03061fb5b7fed76389d5af8f2e0ddb09f8c70d1333abbb62582835e10accb
 	event Mint(address indexed minter, uint256 tokenAmount, uint256 assetAmount, uint256 price);
 
-	// topic: 0x743033787f4738ff4d6a7225ce2bd0977ee5f86b91a902a58f5e4d0b297b4644
 	event Burn(address indexed burner, uint256 tokenAmount, uint256 assetAmount, uint256 price);
 
+	event FlashBorrow(address borrower, address target, address loanToken, uint256 loanAmount);
+
 	mapping(address => uint256) internal balances;
 	mapping(address => mapping(address => uint256)) internal allowed;
 	uint256 internal totalSupply_;

contracts/connectors/loantoken/LoanToken.sol

@@ -7,7 +7,6 @@ pragma solidity 0.5.17;
 
 import "./AdvancedTokenStorage.sol";
 
-//@todo can I change this proxy to EIP-1822 proxy standard, please. https://eips.ethereum.org/EIPS/eip-1822. It's really hard to work with this.
 contract LoanToken is AdvancedTokenStorage {
 	// It is important to maintain the variables order so the delegate calls can access sovrynContractAddress and wrbtcTokenAddress
 	address public sovrynContractAddress;

contracts/connectors/loantoken/LoanTokenBase.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 
@@ -13,7 +13,7 @@ import "../../openzeppelin/Address.sol";
 import "../../interfaces/IWrbtcERC20.sol";
 import "./Pausable.sol";
 
-contract LoanTokenBase is ReentrancyGuard, Ownable {
+contract LoanTokenBase is ReentrancyGuard, Ownable, Pausable {
 	uint256 internal constant WEI_PRECISION = 10**18;
 	uint256 internal constant WEI_PERCENT_PRECISION = 10**20;
 

contracts/connectors/loantoken/LoanTokenLogicDai.sol

@@ -116,7 +116,6 @@ contract LoanTokenLogicDai is LoanTokenLogicStandard {
 		return returnData;
 	}
 
-	// ***** NOTE: Reentrancy is allowed here to allow flashloan use cases *****
 	function borrow(
 		bytes32 loanId, // 0 if new loan
 		uint256 withdrawAmount,
@@ -125,7 +124,7 @@ contract LoanTokenLogicDai is LoanTokenLogicStandard {
 		address collateralToken, // if address(0), this means ETH and ETH must be sent with the call or loanId must be provided
 		address borrower,
 		address receiver,
-		bytes memory /*loanDataBytes*/ // arbitrary order data (for future use)
+		bytes memory // arbitrary order data (for future use) /*loanDataBytes*/
 	)
 		public
 		payable

contracts/connectors/loantoken/LoanTokenLogicStandard.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 
@@ -11,12 +11,14 @@ import "./interfaces/ProtocolLike.sol";
 import "./interfaces/FeedsLike.sol";
 
 contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
+	using SafeMath for uint256;
 	using SignedSafeMath for int256;
 
 	// DON'T ADD VARIABLES HERE, PLEASE
 
-	uint256 public constant VERSION = 5;
+	uint256 public constant VERSION = 6;
 	address internal constant arbitraryCaller = 0x000F400e6818158D541C3EBE45FE3AA0d47372FF;
+	bytes32 internal constant iToken_ProfitSoFar = 0x37aa2b7d583612f016e4a4de4292cb015139b3d7762663d06a53964912ea2fb6; // keccak256("iToken_ProfitSoFar")
 
 	function() external {
 		revert("loan token logic - fallback not allowed");
@@ -53,7 +55,6 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
         payable
         nonReentrant
         pausable(msg.sig)
-        settlesInterest
         returns (bytes memory)
     {
         require(borrowAmount != 0, "38");
@@ -73,6 +74,8 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
         // transfer assets to calling contract
         _safeTransfer(loanTokenAddress, borrower, borrowAmount, "39");
 
+		emit FlashBorrow(borrower, target, loanTokenAddress, borrowAmount);
+
         bytes memory callData;
         if (bytes(signature).length == 0) {
             callData = data;
@@ -123,11 +126,11 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		address collateralTokenAddress, // if address(0), this means ETH and ETH must be sent with the call or loanId must be provided
 		address borrower,
 		address receiver,
-		bytes memory /*loanDataBytes*/ // arbitrary order data (for future use)
+		bytes memory // arbitrary order data (for future use) /*loanDataBytes*/
 	)
 		public
 		payable
-		nonReentrant //note: needs to be removed to allow flashloan use cases
+		nonReentrant
 		hasEarlyAccessToken
 		returns (
 			uint256,
@@ -146,7 +149,7 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		require(collateralTokenAddress != address(0) || msg.value != 0 || loanId != 0, "9");
 
 		// ensures authorized use of existing loan
-        require(loanId == 0 || msg.sender == borrower, "unauthorized use of existing loan");
+		require(loanId == 0 || msg.sender == borrower, "unauthorized use of existing loan");
 
 		if (collateralTokenAddress == address(0)) {
 			collateralTokenAddress = wrbtcTokenAddress;
@@ -215,7 +218,7 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		require(collateralTokenAddress != loanTokenAddress, "11");
 
 		// ensures authorized use of existing loan
-        require(loanId == 0 || msg.sender == trader, "unauthorized use of existing loan");
+		require(loanId == 0 || msg.sender == trader, "unauthorized use of existing loan");
 
 		//temporary: limit transaction size
 		if (transactionLimit[collateralTokenAddress] > 0) require(collateralTokenSent <= transactionLimit[collateralTokenAddress]);
@@ -274,6 +277,7 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 				_from,
 				_to,
 				_value,
+				//allowed[_from][msg.sender]
 				ProtocolLike(sovrynContractAddress).isLoanPool(msg.sender) ? uint256(-1) : allowed[_from][msg.sender]
 			);
 	}
@@ -285,14 +289,13 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		uint256 _allowanceAmount
 	) internal returns (bool) {
 		if (_allowanceAmount != uint256(-1)) {
-			require(_value <= _allowanceAmount, "14");
-			allowed[_from][msg.sender] = _allowanceAmount.sub(_value);
+			allowed[_from][msg.sender] = _allowanceAmount.sub(_value, "14");
 		}
 
-		uint256 _balancesFrom = balances[_from];
-		require(_value <= _balancesFrom && _to != address(0), "14");
+		require(_to != address(0), "15");
 
-		uint256 _balancesFromNew = _balancesFrom.sub(_value);
+		uint256 _balancesFrom = balances[_from];
+		uint256 _balancesFromNew = _balancesFrom.sub(_value, "16");
 		balances[_from] = _balancesFromNew;
 
 		uint256 _balancesTo = balances[_to];
@@ -322,14 +325,13 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		uint256 _newBalance,
 		uint256 _currentPrice
 	) internal {
-		// keccak256("iToken_ProfitSoFar")
-		bytes32 slot = keccak256(abi.encodePacked(_user, uint256(0x37aa2b7d583612f016e4a4de4292cb015139b3d7762663d06a53964912ea2fb6)));
+		bytes32 slot = keccak256(abi.encodePacked(_user, iToken_ProfitSoFar));
 
-		uint256 _currentProfit;
-		if (_oldBalance != 0 && _newBalance != 0) {
-			_currentProfit = _profitOf(slot, _oldBalance, _currentPrice, checkpointPrices_[_user]);
-		} else if (_newBalance == 0) {
+		int256 _currentProfit;
+		if (_newBalance == 0) {
 			_currentPrice = 0;
+		} else if (_oldBalance != 0) {
+			_currentProfit = _profitOf(slot, _oldBalance, _currentPrice, checkpointPrices_[_user]);
 		}
 
 		assembly {
@@ -341,9 +343,8 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 
 	/* Public View functions */
 
-	function profitOf(address user) public view returns (uint256) {
-		// keccak256("iToken_ProfitSoFar")
-		bytes32 slot = keccak256(abi.encodePacked(user, uint256(0x37aa2b7d583612f016e4a4de4292cb015139b3d7762663d06a53964912ea2fb6)));
+	function profitOf(address user) public view returns (int256) {
+		bytes32 slot = keccak256(abi.encodePacked(user, iToken_ProfitSoFar));
 
 		return _profitOf(slot, balances[user], tokenPrice(), checkpointPrices_[user]);
 	}
@@ -353,31 +354,16 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		uint256 _balance,
 		uint256 _currentPrice,
 		uint256 _checkpointPrice
-	) internal view returns (uint256) {
+	) internal view returns (int256 profitSoFar) {
 		if (_checkpointPrice == 0) {
 			return 0;
 		}
 
-		uint256 profitSoFar;
-		uint256 profitDiff;
-
 		assembly {
 			profitSoFar := sload(slot)
 		}
 
-		if (_currentPrice > _checkpointPrice) {
-			profitDiff = _balance.mul(_currentPrice - _checkpointPrice).div(10**18);
-			profitSoFar = profitSoFar.add(profitDiff);
-		} else {
-			profitDiff = _balance.mul(_checkpointPrice - _currentPrice).div(10**18);
-			if (profitSoFar > profitDiff) {
-				profitSoFar = profitSoFar - profitDiff;
-			} else {
-				profitSoFar = 0;
-			}
-		}
-
-		return profitSoFar;
+		profitSoFar = int256(_currentPrice).sub(int256(_checkpointPrice)).mul(int256(_balance)).div(sWEI_PRECISION).add(profitSoFar);
 	}
 
 	function tokenPrice() public view returns (uint256 price) {
@@ -397,7 +383,7 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		uint256 totalSupply = _totalAssetSupply(0);
 		uint256 totalBorrow = totalAssetBorrow();
 		if (totalSupply > totalBorrow) {
-			return totalSupply.sub(totalBorrow);
+			return totalSupply - totalBorrow;
 		}
 	}
 
@@ -572,6 +558,7 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		require(burnAmount != 0, "19");
 
 		if (burnAmount > balanceOf(msg.sender)) {
+			require(burnAmount == uint256(-1), "32");
 			burnAmount = balanceOf(msg.sender);
 		}
 
@@ -711,7 +698,7 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		bytes32 loanParamsId = loanParamsIds[uint256(keccak256(abi.encodePacked(collateralTokenAddress, withdrawAmountExist)))];
 		// converting to initialMargin
 		leverageAmount = SafeMath.div(10**38, leverageAmount);
-		(sentAmounts[1], sentAmounts[4]) = ProtocolLike(sovrynContractAddress).borrowOrTradeFromPool.value(msgValue)( // newPrincipal, newCollateral
+		(sentAmounts[1], sentAmounts[4]) = ProtocolLike(sovrynContractAddress).borrowOrTradeFromPool.value(msgValue)( //newPrincipal,newCollateral
 			loanParamsId,
 			loanId,
 			withdrawAmountExist,
@@ -824,7 +811,7 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 	function _avgBorrowInterestRate(uint256 assetBorrow) internal view returns (uint256) {
 		if (assetBorrow != 0) {
 			(uint256 interestOwedPerDay, ) = _getAllInterest();
-			return interestOwedPerDay.mul(10**20).div(assetBorrow).mul(365);
+			return interestOwedPerDay.mul(10**20).mul(365).div(assetBorrow);
 		}
 	}
 
@@ -932,6 +919,17 @@ contract LoanTokenLogicStandard is LoanTokenSettingsLowerAdmin {
 		}
 	}
 
+	function _adjustValue(
+		uint256 interestRate,
+		uint256 maxDuration,
+		uint256 marginAmount
+	) internal pure returns (uint256) {
+		return
+			maxDuration != 0
+				? interestRate.mul(WEI_PERCENT_PRECISION).mul(maxDuration).div(365 days).div(marginAmount).add(WEI_PERCENT_PRECISION)
+				: WEI_PERCENT_PRECISION;
+	}
+
 	/**
 	 * used to read externally from the smart contract to see if a function is paused
 	 * returns a bool

contracts/connectors/loantoken/LoanTokenSettingsLowerAdmin.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 

contracts/connectors/loantoken/Pausable.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 

contracts/connectors/loantoken/interfaces/FeedsLike.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 

contracts/connectors/loantoken/interfaces/ProtocolLike.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 

contracts/connectors/loantoken/interfaces/ProtocolSettingsLike.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 

contracts/core/Objects.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 

contracts/core/Protocol.sol

@@ -1,5 +1,5 @@
 /**
- * Copyright 2017-2020, bZeroX, LLC. All Rights Reserved.
+ * Copyright 2017-2021, bZeroX, LLC. All Rights Reserved.
  * Licensed under the Apache License, Version 2.0.
  */
 
@@ -8,7 +8,6 @@ pragma experimental ABIEncoderV2;
 
 import "./State.sol";
 
-//@todo can I change this proxy to EIP-1822 proxy standard, please. https://eips.ethereum.org/EIPS/eip-1822.
 contract sovrynProtocol is State {
 	function() external payable {
 		if (gasleft() <= 2300) {