Sending ether from one contract to another, with a parameter

Question

Similar code to this works in other contracts, but not this one. I'm getting a gas error: "errored: Error: gas required exceeds allowance or always failing transaction".

I've narrowed it down to the line causing the problem. What is wrong with this call, and is there any way to get a more descriptive error?

contract GuessTheRandomNumberChallenge {
    uint8 answer;

    function GuessTheRandomNumberChallenge() public payable {
        require(msg.value == 1 ether);
    }

    function guess(uint8 n) public payable {
        require(msg.value == 1 ether);

        //do stuff
    }
}

GuessTheRandomNumberChallenge public handle;

constructor() public payable {
    handle = GuessTheRandomNumberChallenge(0x123123mycontractaddress);
}

function check() public {
    handle.guess.value(1 ether)(83); //PROBLEM LINE
}

Answer 1

Possible issues I can think of:

• Insufficient balance in the contract to send the 1 ether.
• The address you provided for the handle is wrong
• Ether is sent to an unpayable fallback

For getting more info, I would suggest using the Remix debugger, and playing around with the contracts in the js-vm.