35.SWC-135_checkExecution

SWC-135_useless statement

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pragma solidity ^0.5.0;

contract DepositBox {
    mapping(address => uint) balance;

    // Accept deposit
    function deposit(uint amount) public payable {
        require(msg.value == amount, 'incorrect amount');
        // Should update user balance
        // balance[msg.sender] == amount;
        // fixed
        balance[msg.sender] = amount;
    }
}

pragma solidity ^0.5.0;

contract Wallet {
    mapping(address => uint) balance;

    // Deposit funds in contract
    function deposit(uint amount) public payable {
        require(msg.value == amount, 'msg.value must be equal to amount');
        balance[msg.sender] = amount;
    }

    // Withdraw funds from contract
    function withdraw(uint amount) public {
        require(amount <= balance[msg.sender], 'amount must be less than balance');

        uint previousBalance = balance[msg.sender];
        balance[msg.sender] = previousBalance - amount;

        // Attempt to send amount from the contract to msg.sender
        // msg.sender.call.value(amount);
        // fixed: 
        (bool success, ) = msg.sender.call.value(amount)("");
        require(success, 'transfer failed');
        // issues#7096,#2707
    }
}

We should prevent useless code in contract and ensure the code will produce the intended effects.