Drop require checks for synthetic tokens

[code423n4]

Handle

hickuphh3

Vulnerability details

Impact

The README states that "the synthetic token is written to never return false." as it inherits from OpenZeppelin's ERC20PresetMinterPauser.

It is also claimed that "We only check the return boolean (success) for erc20 methods on the payment token not for the synthetic token", but this is not true. LongShort.sol does in fact check that the transfer() and transferFrom() methods returns true (L855 - 857, 900-906, 961-963, 1015-1020).

Recommended Mitigation Steps

Since synthetic tokens have been engineered to always return true, consider dropping the require checks to save gas.

[JasoonS]

Thanks