Add testFulFillRandomWordsPicksAWinnerResetsAndSendMoney test

Author: Omid Bodaghi

script/Interactions.s.sol

@@ -50,7 +50,7 @@ contract FundSubscription is Script, CodeConstants {
 
         if (block.chainid == LOCAL_CHAIN_ID) {
             vm.startBroadcast();
-            VRFCoordinatorV2_5Mock(vrfCoordinator).fundSubscription(subscriptionId, FUND_AMOUNT);
+            VRFCoordinatorV2_5Mock(vrfCoordinator).fundSubscription(subscriptionId, FUND_AMOUNT * 100);
             vm.stopBroadcast();
         } else {
             vm.startBroadcast();

src/Raffle.sol

@@ -149,4 +149,12 @@ contract Raffle is VRFConsumerBaseV2Plus {
     function getPlayer(uint256 index) external view returns (address) {
         return s_players[index];
     }
+
+    function getLastTimeStamp() external view returns (uint256) {
+        return s_lastTimeStamp;
+    }
+
+    function getRecentWinner() external view returns (address) {
+        return s_recentWinner;
+    }
 }

test/unit/RaffleTest.s.sol

@@ -6,6 +6,7 @@ import {DeployRaffle} from "../../script/DeployRaffle.s.sol";
 import {HelperConfig} from "../../script/HelperConfig.s.sol";
 import {Raffle} from "../../src/Raffle.sol";
 import {Vm} from "forge-std/Vm.sol";
+import {VRFCoordinatorV2_5Mock} from "@chainlink/contracts/src/v0.8/vrf/mocks/VRFCoordinatorV2_5Mock.sol";
 
 contract RaffleTest is Test {
     Raffle public raffle;
@@ -136,4 +137,40 @@ contract RaffleTest is Test {
         assert(uint256(requestId) > 0);
         assert(uint256(raffleState) == 1);
     }
+
+    // FULFILL RANDOM WORDS
+    function testFulfillRandomWordsCanOnlyBeCalledAfterPerformUpkeep(uint256 randomRequestId) public raffleEntered {
+        vm.expectRevert(VRFCoordinatorV2_5Mock.InvalidRequest.selector);
+        VRFCoordinatorV2_5Mock(vrfCoordinator).fulfillRandomWords(randomRequestId, address(raffle));
+    }
+
+    function testFulFillRandomWordsPicksAWinnerResetsAndSendMoney() public raffleEntered {
+        uint256 additionalEntrants = 3;
+        uint256 startingIndex = 1;
+        address expectedWinner = address(1);
+        for (uint256 i = 1; i < startingIndex + additionalEntrants; i++) {
+            address newPlayer = address(uint160(i));
+            hoax(newPlayer, 1 ether);
+            raffle.enterRaffle{value: entranceFee}();
+        }
+        uint256 startingTimeStamp = raffle.getLastTimeStamp();
+        uint256 winnerStartingBalance = expectedWinner.balance;
+
+        vm.recordLogs();
+        raffle.performUpkeep("");
+        Vm.Log[] memory entries = vm.getRecordedLogs();
+        bytes32 requestId = entries[1].topics[1];
+        VRFCoordinatorV2_5Mock(vrfCoordinator).fulfillRandomWords(uint256(requestId), address(raffle));
+
+        address recentWinner = raffle.getRecentWinner();
+        Raffle.RaffleState raffleState = raffle.getRaffleState();
+        uint256 winnerBalance = recentWinner.balance;
+        uint256 endingTimeStamp = raffle.getLastTimeStamp();
+        uint256 prize = entranceFee * (additionalEntrants + 1);
+
+        assert(recentWinner == expectedWinner);
+        assert(uint256(raffleState) == 0);
+        assert(winnerBalance == winnerStartingBalance + prize);
+        assert(endingTimeStamp > startingTimeStamp);
+    }
 }