Paladin - Warden Pledges contest - RockingMiles's results

Unnecessary index init

In for loops you initialize the index to start from 0, but it already initialized to 0 in default and this assignment cost gas. It is more clear and gas efficient to declare without assigning 0 and will have the same meaning:

Code instance:

    WardenPledge.sol, 547

Short the following require messages

The following require messages are of length more than 32 and we think are short enough to short them into exactly 32 characters such that it will be placed in one slot of memory and the require function will cost less gas. The list:

Code instances:

    Solidity file: Ownable.sol, In line 70, Require message length to shorten: 38, The message: Ownable: new owner is the zero address
    Solidity file: Address.sol, In line 189, Require message length to shorten: 38, The message: Address: delegate call to non-contract
    Solidity file: Address.sol, In line 134, Require message length to shorten: 38, The message: Address: insufficient balance for call
    Solidity file: Address.sol, In line 162, Require message length to shorten: 36, The message: Address: static call to non-contract

Use != 0 instead of > 0

Using != 0 is slightly cheaper than > 0. (see https://github.com/code-423n4/2021-12-maple-findings/issues/75 for similar issue)

Code instances:

    Address.sol, 61: change 'balance > 0' to 'balance != 0'
    WardenPledge.sol, 245: change 'balance > 0' to 'balance != 0'
    Address.sol, 134: change 'balance > 0' to 'balance != 0'

Consider inline the following functions to save gas

You can inline the following functions instead of writing a specific function to save gas.
(see https://github.com/code-423n4/2021-11-nested-findings/issues/167 for a similar issue.)

Code instances

    Context.sol, _msgData, { return msg.data; }
    Context.sol, _msgSender, { return msg.sender; }
    WardenPledge.sol, _getRoundedTimestamp, { return (timestamp / WEEK) * WEEK; }
    Address.sol, functionCall, { return functionCallWithValue(target, data, 0, errorMessage); }

Inline one time use functions

The following functions are used exactly once. Therefore you can inline them and save gas and improve code clearness.

Code instances:

    Ownable.sol, _checkOwner
    SafeERC20.sol, safeTransfer
    Pausable.sol, _requireNotPaused
    Address.sol, functionCall
    Pausable.sol, _requirePaused

Do not cache msg.sender

We recommend not to cache msg.sender since calling it is 2 gas while reading a variable is more.

Code instance:

    https://github.com/code-423n4/2022-10-paladin/tree/main/contracts/WardenPledge.sol#L309