Hello, first off I’d like to say that I’m a noob in Solidity so this issue might sound so trivial, pls bear with me. I’m running into a compiler error on line 61 (Stack too deep). I suppose an easy fix would be to break blocks #2 and #3 into smaller functions but still be able to return the results on #4 for the parent function (#1). Basically, I’m would like to call the ‘buy’ function and then return #4 while breaking blocks #2 and #3 into smaller functions as a workaround “Stack too deep” error. How do I achieve this? Any help would be appreciated.
// Main function (#1)
function buy(address baseToken, address token, address exchangeRouterAddress) public payable returns (uint256, uint256, uint256, uint256, uint256, uint256) {
uint256[] memory gas = new uint256[](2);
IUniswapV2Router02 exchangeRouter = IUniswapV2Router02(exchangeRouterAddress);
IERC20 _token = IERC20(token);
IERC20 _baseToken = IERC20(baseToken);
address[] memory path = new address[](2);
if(baseToken != exchangeRouter.WETH()) {
path[0] = exchangeRouter.WETH();
path[1] = baseToken;
exchangeRouter.swapExactETHForTokensSupportingFeeOnTransferTokens{value: msg.value}(0, path, address(this), block.timestamp + 20);
}
else {
IWETH(baseToken).deposit{value: msg.value}();
}
uint256 amount = _baseToken.balanceOf(address(this));
// Nest function 1 (#2)
path = new address[](2);
path[0] = baseToken;
path[1] = token;
uint256 expectedToken = exchangeRouter.getAmountsOut(amount, path)[1];
_baseToken.approve(exchangeRouterAddress, type(uint256).max);
uint256 startGas = gasleft();
exchangeRouter.swapExactTokensForTokensSupportingFeeOnTransferTokens(amount, 0, path, address(this), block.timestamp + 20);
gas[0] = startGas - gasleft();
uint256 receivedToken = _token.balanceOf(address(this));
// Nest function 2 (#3)
path = new address[](2);
path[0] = token;
path[1] = baseToken;
uint256 expectedBaseToken = exchangeRouter.getAmountsOut(receivedToken, path)[1];
_token.approve(exchangeRouterAddress, type(uint256).max);
startGas = gasleft();
exchangeRouter.swapExactTokensForTokensSupportingFeeOnTransferTokens(receivedToken, 0, path, address(this), block.timestamp + 20);
gas[1] = startGas - gasleft();
uint256 receivedBaseToken = _baseToken.balanceOf(address(this));
// Finally return all results at once (#4)
return (expectedToken, receivedToken, gas[0], expectedBaseToken, receivedBaseToken, gas[1]);
}
