Why is the address.call function failing?

Question

Im trying to run the following solidity-by-example on remix:

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.10;

contract Payable {
// Payable address can receive Ether
address payable public owner;

// Payable constructor can receive Ether
constructor() payable {
    owner = payable(msg.sender);
}

// Function to deposit Ether into this contract.
// Call this function along with some Ether.
// The balance of this contract will be automatically updated.
function deposit() public payable {}

// Call this function along with some Ether.
// The function will throw an error since this function is not payable.
function notPayable() public {}

// Function to withdraw all Ether from this contract.
function withdraw() public {
    // get the amount of Ether stored in this contract
    uint amount = address(this).balance;

    // send all Ether to owner
    // Owner can receive Ether since the address of owner is payable
    (bool success, ) = owner.call{value: amount}("");
    require(success, "Failed to send Ether");
}

// Function to transfer Ether from this contract to address from input
function transfer(address payable _to, uint _amount) public {
    // Note that "to" is declared as payable
    (bool success, ) = _to.call{value: _amount}("");
    require(success, "Failed to send Ether");
}

}

Once deployed, when I call the "transfer" function using any of the remix' javascript VM addresses as the _to and the number 1 as _amount its reverting with the following:

revert The transaction has been reverted to the initial state. Reason provided by the contract: "Failed to send Ether".

I don't think it has to do with access but with how I am introducing the attributes. Can anyone point me the right way to do it? Thank you in advance!

Answer 1

One simple solution is to add this function to your code, to correctly receive tokens to the contract:

receive() external payable { }

I found sending ETH to the contract posed errors regardless of gas, which would be expected without the above function.

Second, you should consider that when you input the amount of ETH you send, unless specified otherwise in your code (ie _amount * 10**18) the amount of ETH sent does not have a decimal. This means that the input of "1" really means "0.000000000000000001 ETH"

Answer 2

tested this smart contract on remix (0.8.11+) was able to

1. deposit 1 ether using deposit function
2. transfer 1 ether to an EOA. Is the _to address a contract in your case? _to address contract can't receive ether without receiver fallback function

also _to address doesn't need to be payable,

function transfer(address  _to, uint _amount) public {}

as call invocation does not need the address to be payable

Answer 3

Your contract probably doesn't have enough ether to send to another account. When deploying, make sure it received enough amount so that later, when calling the transfer function, it can perform the transfer.