Gas Optimziation: Unnecessary pairBalance call

[code423n4]

Handle

gzeon

Vulnerability details

Impact

If msg.sender == issuer, we don't need to call pairBalance(msg.sender) https://github.com/code-423n4/2022-01-trader-joe/blob/a1579f6453bc4bf9fb0db9c627beaa41135438ed/contracts/LaunchEvent.sol#L447

        uint256 balance = pairBalance(msg.sender);
        user.hasWithdrawnPair = true;

        if (msg.sender == issuer) {
            balance = lpSupply / 2;

            emit IssuerLiquidityWithdrawn(msg.sender, address(pair), balance);

            if (tokenReserve > 0) {
                uint256 amount = tokenReserve;
                tokenReserve = 0;
                token.transfer(msg.sender, amount);
            }
        } else {
            emit UserLiquidityWithdrawn(msg.sender, address(pair), balance);
        }

to

        uint256 balance;
        user.hasWithdrawnPair = true;

        if (msg.sender == issuer) {
            balance = lpSupply / 2;

            emit IssuerLiquidityWithdrawn(msg.sender, address(pair), balance);

            if (tokenReserve > 0) {
                uint256 amount = tokenReserve;
                tokenReserve = 0;
                token.transfer(msg.sender, amount);
            }
        } else {
            balance = pairBalance(msg.sender);
            emit UserLiquidityWithdrawn(msg.sender, address(pair), balance);
        }

[cryptofish7]

Fix: https://github.com/traderjoe-xyz/rocket-joe/pull/126