FungibleFractionsDO Manual Review Findings

FFD-01M: Potential Non-Standard EIP-1155 Behaviour

Type	Severity	Location
Standard Conformity		FungibleFractionsDO.sol:L395

Description:

Although not clearly outlined as incorrect by the EIP-1155 standard, a transfer of zero will presently fail in the FungibleFractionsDO implementation if the transferrer never held the ID of the asset being sent.

Impact:

As the EIP-1155 standard does not contradict the FungibleFractionsDO implementation, we consider this to be an informational observation on the implementation.

Example:

Copy
385function _decreaseBalance(DiidData storage diidd, uint256 id, uint256 value, DataPoint, bytes32 diidFrom) internal {
386    uint256 diidBalance = diidd.balances[id];
387    if (diidBalance < value) {
388        revert InsufficientBalance(diidFrom, id, diidBalance, value);
389    }
390    unchecked {
391        diidBalance -= value;
392    }
393    diidd.balances[id] = diidBalance;
394    if (diidBalance == 0) {
395        if (!diidd.ids.remove(id)) revert DiidIdNotFound(id);
396    }
397}

Recommendation:

We advise this to be evaluated and potentially supported as it may cause integration complications by systems that expect transfers to always succeed even if zero.

Alleviation (c6b23c23d8bcd8cce85049ad959cbd711a37126b):

The code was updated to permit a transfer of zero to be executed, addressing this exhibit.