I am struggling to figure out the abi.decode function when using it to decode the bytes coming as output from a reverted low level call to another contract. The way I am using it is by calling the CheckContract() function on contract A:

function CheckContract() public {
    require (!isContract(msg.sender),"No contracts allowed");}

from these two functions on contract B:

function checkWithDecode() public returns (bool, string memory) {
    (bool success, bytes memory data) = CheckerAddress.call(abi.encodeWithSignature("CheckContract()"));
    string memory reply = abi.decode(data, (string));
    return (success, reply);

function checkWithoutDecode() public returns (bool, bytes memory) {
    (bool success, bytes memory reply) = CheckerAddress.call(abi.encodeWithSignature("CheckContract()"));
    return (success, reply);

As expected, CheckContract reverts on both of the cases and the boolean is false. When called from checkWithoutDecode the transaction is successful and the output is:

    "0": "bool: false",
    "1": "bytes: 0x08c379a0000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000144e6f20636f6e74726163747320616c6c6f776564000000000000000000000000"

However, when I attempt to run the decode method on the bytes I receive, using checkWithDecode, the whole transaction fails reverting just at abi.decode. Can anyone explain what is wrong with it? How should I decode that output?

Thanks in advance



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