How to mock msg.sender.call?

[0xCLARITY]

I have a 721 mint function for a free mint that attempts to refund any excess balance sent:

    error RefundFailed(address to, uint256 amount);
        
    function mint() external payable {
        _mint(msg.sender, 1);
        
        // Refund user if too much ETH was accidentally sent for minting.
        if (msg.value > 0) {
            (bool success, ) = msg.sender.call{value: msg.value}("");
            if (!success) revert RefundFailed(msg.sender, msg.value);
        }
    }

So, I thought, I would do something like this in my test file:

    function test_mint_refund_failure() external {
        address alice = address(128);
        vm.deal(alice, 10**18);

        vm.startPrank(alice, alice);
        vm.mockCall(alice, abi.encodeWithSelector(alice.call.selector), abi.encode(false, ""));
        vm.expectRevert(RefundFailed.selector);
        contract.mint{value: 100}();
    }

But, for reasons slightly outside of my understanding of Solidity / the EVM - alice.call does not have a function selector.

How would I go about mocking the call or manipulating the VM state such that I can hit my revert RefundFailed() line?

[onbjerg]

address.call("") just invokes the CALL opcode with no calldata, so you do not need to use vm.mockCall. Although, in order to hit your path, you would essentially need to create a contract with a payable receive function that reverts. Returning false does not do anything - the success boolean just indicates whether the CALL opcode encountered a revert or not.