Uniswap's Multicall library incorrectly parses revert reason length and does not bubble up custom errors

Uniswap's Multicall library only bubbles up revert reason when the length of the byte array is 68 >= (4 for error selector + 32 for string length + at least 32 for string content)

This leads to empty reverts even if the underlying contract implements custom errors.

Yearn-ERC4626-Router/src/external/Multicall.sol

Lines 15 to 24 in 6816577

    
           (bool success, bytes memory result) = address(this).delegatecall(data[i]); 
        
           if (!success) { 
        
               // Next 5 lines from https://ethereum.stackexchange.com/a/83577 
        
               if (result.length < 68) revert(); 
        
               assembly { 
        
                   result := add(result, 0x04) 
        
               } 
        
               revert(abi.decode(result, (string))); 
        
           }

Furthermore it seems like it incorrectly attempts to splice revertData, rather than splicing the 4 bytes selector, it shifts the pointer to the length of the bytes by 4 and leads to high length bytes. Ends up relying on abi.decode's behavior to deal with incorrect string length

Discussion from the Uniswap repo here: Uniswap/v3-periphery#254

Would be nice to replace this with a better (and correct) way to pass the revert data like from OZ

https://github.com/OpenZeppelin/openzeppelin-contracts/blob/17a8955cd8ed2c9a269421a11c2e2774b796e305/contracts/utils/Address.sol#L143-L158

	(bool success, bytes memory result) = address(this).delegatecall(data[i]);

	if (!success) {
	// Next 5 lines from https://ethereum.stackexchange.com/a/83577
	if (result.length < 68) revert();
	assembly {
	result := add(result, 0x04)
	}
	revert(abi.decode(result, (string)));
	}