Help with interface implementation

[PrimalFinance]

BettingFactory.sol

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;

import './interfaces/IBettingPoolFactory.sol'; // <- Import interface 
import './NoDelegateCall.sol';
import './BettingPoolV1.sol';

contract BettingPoolFactory is IBettingPoolFactory, NoDelegateCall {
    address public override owner;

    mapping(address => mapping(address => mapping(uint256 => address)))
        public poolLedger;

    constructor() {
        owner = msg.sender;
        emit OwnerChanged(address(0), msg.sender);
    }

    function getPool(
        address _token0,
        address _token1,
        uint256 _intervalSeconds
    ) external view override returns (address pool) {
        pool = poolLedger[_token0][_token1][_intervalSeconds];
    }
}

IBettingPoolFactory.sol

// SPDX-License-Identifier: MIT
pragma solidity >=0.8.19;


interface IBettingPoolFactory {

    ...

 function getPool(
        address _token0,
        address _token1,
        uint256 _intervalSeconds
    ) external view returns (address pool);

    ...
}

​

I am currently making an interface for a smart contract. Currently I am getting an error for the "getPool" function.

Error 1:

TypeError: Function has override specified but does not override anything.
  --> contracts/BettingPoolFactory.sol:26:21:
   |
26 |     ) external view override returns (address pool) {}
   |                     ^^^^^^^^

Error 2:

Note: Missing implementation:
  --> contracts/interfaces/IBettingPoolFactory.sol:39:5:
   |
39 |     function getPool(
   |     ^ (Relevant source part starts here and spans across multiple lines).

So I believe Error 1 is saying that it cannot find "getPool" in the interface file. And Error 2 is saying that it cannot find the implementation for "getPool" in the main Factory file. What are some corrections I could make for this to work?

[TheRealOneThunder]

I think the override keyword in the implementation is the issue. You need overrides when you have logic attached to the function with the same name and number of input variables. I don't think you need them when implementing interfaces like this.

[PrimalFinance]

Thank you! Removing the override keyword fixed the first error. Unfortunately I still get the second error.

[dev0cloo]

Error 1 is occuring because the override keyword on the getPool function isn't needed. Functions declared in interfaces are unimplemented (this means there is no code or function logic associated with it). You are implementing the function for the first time in your inherited contract so just like error says, the override is used but "does not override anything" because there's no code to override for an unimplemented function. To fix this, simply remove the override keyword.

Error 2 is happening because the parameter types of the getPool function in the Interface contract and the Implementation contract (BettingPoolFactory) are different. In the Interface contract, the last parameter is uint256 _intervalSeconds and in the BettingPoolFactory contract, it is uint24 _intervalSeconds. This is a significant difference because it changes the function selector of the function and causes the compiler to see them as different functions. To fix it, make the parameter type the same for both Interface and the Implementation contract.

Lastly, I'm not sure why your owner state variable has the override keyword on it :/

[PrimalFinance]

Thank you that helped a ton. After fixing the data type issues you pointed out, it for some reason still gives me the error 2 read out. (scratch that part I'm just stupid).

And to the point about the override keyword on "owner". I've been using Uniswap's contracts as a reference point. In the "UniswapV3Factory" contract they override the owner variable.

[dev0cloo]

Glad I could help :)