Lesson 9: Contract "Raffle" should be marked as abstract

[parishill25]

Hi,
I got this error while trying to compile my solidity file :

Function has override specified but does not override anything.
  --> contracts/Raffle.sol:35:16:
   |
35 |     ) internal override {}
   |                ^^^^^^^^


TypeError: Contract "Raffle" should be marked as abstract.
 --> contracts/Raffle.sol:9:1:
  |
9 | contract Raffle is VRFConsumerBaseV2 {
  | ^ (Relevant source part starts here and spans across multiple lines).
Note: Missing implementation: 
   --> @chainlink/contracts/src/v0.8/VRFConsumerBaseV2.sol:122:3:
    |
122 |   function fulfillRandomWords(uint256 requestId, uint256[] memory randomWords) internal virtual;
    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^


Error HH600: Compilation failed

This is my Raflle code :

// SPDX-License-Identifier: SEE LICENSE IN LICENSE

pragma solidity ^0.8.7;

error Raffle_notEnoughETHEntered();

import "@chainlink/contracts/src/v0.8/VRFConsumerBaseV2.sol";

contract Raffle is VRFConsumerBaseV2 {
    uint256 private immutable i_entranceFee;
    address payable[] private s_players;

    event RaffleEnter(address indexed player);

    constructor(
        address vrfCoordinatorV2,
        uint256 entranceFee
    ) VRFConsumerBaseV2(vrfCoordinatorV2) {
        i_entranceFee = entranceFee;
    }

    function enterRaffle() public payable {
        if (msg.value < i_entranceFee) {
            revert Raffle_notEnoughETHEntered();
        }
        s_players.push(payable(msg.sender));
        emit RaffleEnter(msg.sender);
    }

    function requestRandomWords() external {}

 
    function fulfillRandomWords(uint256 requestId, uint256[] memory randomWords) internal override{}

    function getEntranceFee() public view returns (uint256) {
        return i_entranceFee;
    }

    function getPlayer(uint256 index) public view returns (address) {
        return s_players[index];
    }
}

[alymurtazamemon]

@parishill25 It looks correct, clean the files by running this command npx hardhat clean and compile the code again npx hardhat compile. It should fix the issue, if it still does not fix the issue then please leave your repo link so I can test it locally.

[azeezabidoye]

I ran into the same problem and I have been stuck ever since.
I will appreciate your help, here is the repo for the project:

https://github.com/azeezabidoye/hardhat-raffle

[soarewee]

@azeezabidoye Try adding this line of code in your Raffle contract:
function fulfillRandomWords(uint256 requestId, uint256[] calldata randomWords) internal override {}

Since Raffle inherited the VRFConsumerBaseV2Plus contract, it needs an implementation for the fulfillRandomWords function - and simply overriding it with nothing solved the problem for me

[umarmahir]

Your answer works, but it may still give an error about the data location of parameters in the function. So, what worked for me was that I changed 'calldata' to 'memory' and it works fine.