Wenwin contest - 0xhacksmithh's results

[Gas-01] Use of uint/int smaller than 32bytes incurs overhead

instances()

File :: src/Lottery.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L36
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L37
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L39

File :: src/LotterySetup.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/LotterySetup.sol#L30-L31

[Gas-02] Multiple address mapping can be combined into a single mapping of an address to a struct, where appropriate.

instances()

File :: src/Lottery.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L37

[Gas-03] Using unchecked blocks to save gas.

Solidity version 0.8+ comes with implicit overflow and underflow checks on unsigned integers. When an overflow or an underflow isn’t possible (as an example, when a comparison is made before the arithmetic operation), some gas can be saved by using an unchecked block. instances()

File :: src/Lottery.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L125
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L172
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L193
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L194
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L205
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L211
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L275

File :: src/LotterySetup.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/LotterySetup.sol#L169

File :: src/RNSourceController.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/RNSourceController.sol#L68

[Gas-04] Avoid compound assignment operator in state variable.

Using compound assignment operators for state variable(like state += x, or state -= x) its more expensive than using operator assignment (like state = state + x or, state = state - x) instances()

File :: src/Lottery.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L129
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L173

[Gas-05] Function guaranteed to revert when called by normal user can be marked as payable

instances()

File :: src/RNSourceController.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/RNSourceController.sol#L77
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/RNSourceController.sol#L89

[Gas-06] Avoid contract existance checks by using low level calls.

instances()

File :: src/Lottery.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L286

[Gas-07] Use require() instead of assert()

instances()

File :: src/LotterySetup.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/LotterySetup.sol#L147

[Gas-08] Setting constructor to payable could save gas.

Saves ~13 gas per instances. instances()

File :: src/Lottery.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L84

[Gas-09] Use public function instead of modifiers

instances()

File :: src/Lottery.sol
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L44
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L52
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L60
https://github.com/code-423n4/2023-03-wenwin/blob/main/src/Lottery.sol#L69