Gas optimization for contracts/TalentLayerEscrow.sol

[Pfed-prog]

The initial struct in contracts/TalentLayerEscrow.sol

        uint256 id;
        address sender;
        address receiver;
        address token;
        uint256 amount;
        uint256 serviceId;
        uint256 proposalId;
        uint16 protocolEscrowFeeRate;
        uint16 originServiceFeeRate;
        uint16 originValidatedProposalFeeRate;
        uint256 disputeId;
        uint256 senderFee;
        uint256 receiverFee;
        uint256 lastInteraction;
        Status status;
        Arbitrator arbitrator;
        bytes arbitratorExtraData;
        uint256 arbitrationFeeTimeout;
    }

change to

    struct Transaction {
        Arbitrator arbitrator;
        bytes arbitratorExtraData;
        uint16 protocolEscrowFeeRate;
        uint16 originServiceFeeRate;
        uint16 originValidatedProposalFeeRate;
        uint256 id;
        address sender;
        address receiver;
        address token;
        uint256 amount;
        uint256 serviceId;
        uint256 proposalId;
        uint256 disputeId;
        uint256 senderFee;
        uint256 receiverFee;
        uint256 lastInteraction;
        Status status;
        uint256 arbitrationFeeTimeout;
    }

#126

further reduced gas estimate to 5096571 from 5198083

There are definitely more gas optimizations

[Pfed-prog]

optimisation of

event Payment(
        uint256 _transactionId,
        PaymentType _paymentType,
        uint256 _amount,
        address _token,
        uint256 _serviceId
    );

to

    event Payment(
        PaymentType _paymentType,
        uint256 _transactionId,
        uint256 _amount,
        address _token,
        uint256 _serviceId
    );

reduces gas to 5095482

[Pfed-prog]

reduction to 5095470

    event OriginValidatedProposalFeeRateReleased(
        address indexed _token,
        uint256 _platformId,
        uint256 _serviceId,
        uint256 _amount
    );

[Pfed-prog]

to 5093526

    event TransactionCreated(
        Arbitrator _arbitrator,
        bytes _arbitratorExtraData,
        uint16 _protocolEscrowFeeRate,
        uint16 _originServiceFeeRate,
        uint16 _originValidatedProposalFeeRate,
        uint256 _transactionId,
        uint256 _senderId,
        uint256 _receiverId,
        address _token,
        uint256 _amount,
        uint256 _serviceId,
        uint256 _arbitrationFeeTimeout
    );

[Pfed-prog]

5092038

function submitEvidence(
        string memory _evidence,
        uint256 _profileId,
        uint256 _transactionId
    )

function claim(address _tokenAddress, uint256 _platformId)

[Pfed-prog]

further areas for optimization:

• fixed size bytes array rather than string or bytes[]
• custom errors to save deployment and runtime costs in case of revert

[0xRomain]

As the deployment of the contract will cost only 0,9$ on Polygon, we will ponderate any deployment optimization that impact deployment gas only and which have impacts on code readability. In most of case here, it reduce the readability here. For example, on struct Transaction it's more readable to start with id, sender, receiver, token, amount..