Volt Protocol contest - TerrierLover's results

Can use block.chainid at constructor in ScalingPriceOracle.sol

Target codebase

https://github.com/code-423n4/2022-03-volt/blob/main/contracts/oracle/ScalingPriceOracle.sol#L78-L82

uint256 chainId;
// solhint-disable-next-line no-inline-assembly
assembly {
    chainId := chainid()
}

There is no need to use assembly to get chainId. See reference.

Potential improvement

uint256 chainId = block.chainid;

Can use Custom Errors at Permissions.sol to reduce both gas cost and contract size

Target codebase

https://github.com/code-423n4/2022-03-volt/blob/main/contracts/core/Permissions.sol#L28-L42

modifier onlyGovernor() {
    require(
        isGovernor(msg.sender),
        "Permissions: Caller is not a governor"
    );
    _;
}

modifier onlyGuardian() {
    require(
        isGuardian(msg.sender),
        "Permissions: Caller is not a guardian"
    );
    _;
}

onlyGovernor and onlyGuardian modifiers are used many places. Hence, using Custom Error can reduce the deployment gas cost.

Potential improvement

Using custom error can reduce the deployment gas cost.

error NotGovernor();
error NotGuardian();

...

modifier onlyGovernor() {
    if(!isGovernor(msg.sender)) {
        revert NotGovernor();
    }
    _;
}

modifier onlyGuardian() {
    if(!isGuardian(msg.sender)) {
        revert NotGuardian();
    }
    _;
}

Deployment gas improvement