Illuminate contest - 0xf15ers's results

1. Use type(uint256).max instead of calculating 2**256-1

• https://github.com/code-423n4/2022-06-illuminate/blob/912be2a90ded4a557f121fe565d12ec48d0c4684/lender/Lender.sol#L84

2. Unhandled return value

• The return value of IERC5095(principalToken(u, m)).mint(msg.sender, a); is not handled.
• Consider adding require() guard to handle the returned bool.

3. Functions returning same value always can be ignored.

• Some functions either revert or return true so return is not necessary in these functions
• for eg.
• https://github.com/code-423n4/2022-06-illuminate/blob/main/marketplace/MarketPlace.sol#L109
• https://github.com/code-423n4/2022-06-illuminate/blob/main/marketplace/MarketPlace.sol#L119
• https://github.com/code-423n4/2022-06-illuminate/blob/main/marketplace/MarketPlace.sol#L98

4. Make public functions external

• The lend() methods in Lender.sol can be converted to external as they are not called inside the contract.
• https://github.com/code-423n4/2022-06-illuminate/blob/912be2a90ded4a557f121fe565d12ec48d0c4684/lender/Lender.sol#L192
• https://github.com/code-423n4/2022-06-illuminate/blob/912be2a90ded4a557f121fe565d12ec48d0c4684/lender/Lender.sol#L247
• ........
• Same for redeem() methods in redeem.sol

5. floating version pragma in ERC5095.sol

• Locking the pragma helps to ensure that contracts do not accidentally get deployed using, for example, an outdated compiler version that might introduce bugs that affect the contract system negatively.
• pragma solidity ^0.8.4;

1. Use prefix increment instead of postfix increment to save gas

• Although unchecked directive is used to save gas, using prefix increment can save more gas.

 function approve(
....................
            unchecked {
                ++i;
            }
    }

2. The length of the loop is calculated in every iteration, caching it can save gas

• https://github.com/code-423n4/2022-06-illuminate/blob/912be2a90ded4a557f121fe565d12ec48d0c4684/lender/Lender.sol#L265

The loop termination condition evaluates the length of the loop on every iteration. Caching it will save gas.

3. Using > 0 costs more gas than != 0 when used on a uint in a require() statement

• In lender.sol's calculateFee(),

function calculateFee(uint256 a) internal view returns (uint256) {
       return feenominator > 0 ? a / feenominator : 0;
   }