[MHR-06C] Potentially Inefficient Array Shift Operation

[vm06007]

MHR-06C: Potentially Inefficient Array Shift Operation

Type	Severity	Location
Gas Optimization		MainHelper.sol:L575-L577

Description:

The referenced ternary condition is meant to assign the last element of the array to the index of the element being removed, however, this will be done inefficiently so when the index being removed is the endPosition.

Example:

while (index < length) {

    if (_getPositionTokenByIndex(_nftId, index) != _poolToken) {
        index += 1;
        continue;
    }

    address poolToken = _getPositionTokenByIndex(
        _nftId,
        endPosition
    );

    isLending
        ? positionLendingTokenData[_nftId][index] = poolToken
        : positionBorrowTokenData[_nftId][index] = poolToken;

    _deleteLastPositionData(
        _nftId,
        _poolToken
    );

    break;
}

Recommendation:

We advise the code to immediately invoke _deleteLastPositionData if the index is equal to the endPosition without fetching the position token by index nor assigning it at the index, greatly reducing the worst-case gas cost of the function.

[vm06007]

Resolved based on suggestion from auditor in https://github.com/wise-foundation/lending-audit/pull/75