TypeError:在合同游戏中，在依赖于参数的查找之后找不到或看不到成员“所有者”

Question

我试图使用“松露测试”测试此合同，但它显示了以下错误："TypeError:成员“所有者”未找到“，或在”owner = gaming.owner();“中的依赖于参数的查找后不可见。

Gaming.sol

pragma solidity ^0.5.0;

contract Gaming {
    /* Our Online gaming contract */
    address owner;
    bool public online;

    struct Player {
        uint wins;
        uint losses;
    }

    mapping (address => Player) public players;

    constructor() public payable {
        owner = msg.sender;
        online = true;
    }

    modifier isOwner() {
        require(msg.sender == owner, "Only owner can call this function");
        _;
    }

}

TestGaming.sol

pragma solidity ^0.5.0;

import "truffle/Assert.sol";
import "truffle/DeployedAddresses.sol";
import "../contracts/Gaming.sol";

contract TestGaming {
    uint public initialBalance = 10 ether;
    Gaming gaming;
    address owner;

    function beforeAll() public {
        gaming = Gaming(DeployedAddresses.Gaming());
        owner = gaming.owner();

    }

    function testWithdrawFunds() public {
        uint ownerBalanceBefore = owner.balance;
        gaming.withdrawFunds();
        uint ownerBalanceAfter = owner.balance;

        Assert.equal (initialBalance, ownerBalanceAfter - ownerBalanceBefore, "The owner's balance should have increased by 10 ether");
}

Answer 1

在稳固性中，默认可见性是internal。对于此代码

address owner;

它的能见度是内在的。Solidity为公共变量分配getter。

address public owner;

您可以很容易地在混合上测试：

contract Test {        
    uint public firstVar=10;
    uint secondVar=50;
  }

如果您将其部署在混合上，您将看到getter用于firstVar，而不是secondVar。

或者您可以为所有者编写getter函数：

 function returnOwner() public view returns (address){
        return owner
    }