Axelar Network contest - nahnah's results

Title: Less code can save gas

Summary

instead of executing the same function in every if statements and then return it. we can put that function in the end line to save gas

POC https://github.com/code-423n4/2022-04-axelar/blob/main/src/AxelarGateway.sol#L294-L334

before '''

    bool burnSuccess = false;

    if (tokenType == TokenType.External) {
        _checkTokenStatus(symbol);

        burnSuccess = _callERC20Token(
            tokenAddress,
            abi.encodeWithSelector(IERC20.transferFrom.selector, sender, address(this), amount)
        );

        if (!burnSuccess) revert BurnFailed(symbol);

        return;
    }

    if (tokenType == TokenType.InternalBurnableFrom) {
        burnSuccess = _callERC20Token(
            tokenAddress,
            abi.encodeWithSelector(IERC20BurnFrom.burnFrom.selector, sender, amount)
        );

        if (!burnSuccess) revert BurnFailed(symbol);

        return;
    }

    burnSuccess = _callERC20Token(
        tokenAddress,
        abi.encodeWithSelector(
            IERC20.transferFrom.selector,
            sender,
            BurnableMintableCappedERC20(tokenAddress).depositAddress(bytes32(0)),
            amount
        )
    );

    if (!burnSuccess) revert BurnFailed(symbol);

    BurnableMintableCappedERC20(tokenAddress).burn(bytes32(0));

'''

after '''

    bool burnSuccess = false;

    if (tokenType == TokenType.External) {
        _checkTokenStatus(symbol);

        burnSuccess = _callERC20Token(
            tokenAddress,
            abi.encodeWithSelector(IERC20.transferFrom.selector, sender, address(this), amount)
        );
    }
    else if (tokenType == TokenType.InternalBurnableFrom) {
        burnSuccess = _callERC20Token(
            tokenAddress,
            abi.encodeWithSelector(IERC20BurnFrom.burnFrom.selector, sender, amount)
        );
    }
    else { 
        burnSuccess = _callERC20Token(
        tokenAddress,
        abi.encodeWithSelector(
            IERC20.transferFrom.selector,
            sender,
            BurnableMintableCappedERC20(tokenAddress).depositAddress(bytes32(0)),
            amount ));
    }

    if (!burnSuccess) revert BurnFailed(symbol);

    BurnableMintableCappedERC20(tokenAddress).burn(bytes32(0));

'''