DeployLottery.s.sol --> failed: panic: arithmetic underflow or overflow

[saikrishna5907]

Hi,

Anyone facing this issue when we try to deploy the raffle contract on anvil

forge script script/DeployLottery.s.sol --rpc-url http://localhost:8545 --account local_anvil --broadcast

error screenshot

when I did some digging found out VRFCoordinatorV2_5Mock is extending SubscriptionAPI (from lib/chainlink-brownie-contracts/contracts/src/v0.8/vrf/dev/SubscriptionAPI.sol)

the error is causing by line number 355

particularly

blockhash(block.number - 1)

here the block.number is 0, so when it evaluates (0 - 1) it is giving the error script failed: panic: arithmetic underflow or overflow (0x11)

I did tried to change/ fix in SubscriptionAPI by adding this line

bytes32 blockHashToUse = block.number > 0 ? blockhash(block.number - 1) : bytes32(0);

but now I get a new error on addConsumer function

coming from here

Can anyone help please?

[EngrPips]

Hello @saikrishna5907, Please show your createSubscription script.

[saikrishna5907]

Hi @EngrPips here is my repo https://github.com/saikrishna5907/lottery-contract

here is my deploy script

CreateSubscription contract

[EngrPips]

Thanks for sharing the repo, I will take a look and point out whatever i find that i think can be causing the issue.

[EngrPips]

Hello @saikrishna5907, I want us to know that whenever you use vm.startBroadcast() in foundry and you did not pass in a private-key, Foundry will automatically use a default private key. Now that this fact is establish lets look into your code and see what is wrong

Here in your createSubscription script you have the below function.

function createSubscription(
        address vrfCoordinator,
        address account
    ) public returns (uint256, address) {
        // create a subscription
        console2.log(
            "Creating a subscription on ChainId:",
            block.chainid,
            account
        );

        vm.startBroadcast();
        uint256 subscriptionId = VRFCoordinatorV2_5Mock(vrfCoordinator)
            .createSubscription();
        vm.stopBroadcast();
        console2.log("Your Subscription Id:", subscriptionId);
        return (subscriptionId, vrfCoordinator);
    }

This function uses vm.startBroadcast() and doesn't pass in any private key, which makes it so that it is the Default Foundry Account that creates the subscription.

So when it got to the point where you wanted to add a consumer to that subscription you use the function below.

function addConsumer(
        address mostRecentlyDeployedLottery,
        address vrfCoordinator,
        uint256 subscriptionId,
        address account
    ) public {
        console2.log(
            "Adding contract:",
            mostRecentlyDeployedLottery,
            "as a consumer"
        );
        console2.log("Using vrfCoordinator:", vrfCoordinator);
        console2.log("Using Subscription:", subscriptionId);
        console2.log("On ChainId:", block.chainid);
        vm.startBroadcast(account);
        VRFCoordinatorV2_5Mock(vrfCoordinator).addConsumer(
            subscriptionId,
            mostRecentlyDeployedLottery
        );
        vm.stopBroadcast();
    }

The addConsumer clearly uses vm.startBroadcast(account) passing in the private key of some account named account, doing that makes it so it the account and not the Default Foundry Account that is sending the account. The subId doesn't recognize this account private key so it reverts with mustBeSubOwner

Suggested Solution
Have your createSubscription as the below and re-run the test, Let see if it works

function createSubscription(
        address vrfCoordinator,
        address account
    ) public returns (uint256, address) {
        // create a subscription
        console2.log(
            "Creating a subscription on ChainId:",
            block.chainid,
            account
        );

        vm.startBroadcast(account);
        uint256 subscriptionId = VRFCoordinatorV2_5Mock(vrfCoordinator)
            .createSubscription();
        vm.stopBroadcast();
        console2.log("Your Subscription Id:", subscriptionId);
        return (subscriptionId, vrfCoordinator);
    }

[saikrishna5907]

Hi @EngrPips my bad, when I said previously it was working its because I has this line at lib/chainlink-brownie-contracts/contracts/src/v0.8/vrf/dev/SubscriptionAPI.sol

bytes32 blockHashToUse = block.number > 0 ? blockhash(block.number - 1) : bytes32(0);

if I remove that I get same error again

[EngrPips]

I didn't need to add any line to any library code for my deployment script to work, So it is strange to me that you needed to add a line, but if that is what it takes for it to work for you, keep the line there till you figure how to resolve it. Re-run your test and send the test output. Please copy the output and paste it here instead of sending pictures. Don't forget to format it properly. Also, comment out your magic line, so the deployment will fail.

[saikrishna5907]

tests was never an issue deploying using the script is what causing the error

here is the test output after commenting the fix added to lib

Ran 21 tests for test/unit/Lottery.t.sol:LotteryTest
[PASS] testCannotEnterLotteryWhenWinnerIsCalculating() (gas: 221724)
[PASS] testCheckUpKeepIfEnoughNotPassed() (gas: 18963)
[PASS] testCheckUpKeepRetunrsTrueWhenAllConditionsAreMet() (gas: 75121)
[PASS] testCheckUpKeepReturnsFalseIfNoBalance() (gas: 22043)
[PASS] testCheckUpKeepReturnsFalseIfThereAreNoPlayersYet() (gas: 20108)
[PASS] testCheckUpKeepReturnsFalseWhenNotOpen() (gas: 216537)
[PASS] testEmitsEnteredLotteryEventWhenPlayerEnters() (gas: 69051)
[PASS] testFulFillRandamWordsCanOnlyCalledAfterPerformUpKeep(uint256) (runs: 256, μ: 80837, ~: 80837)
[PASS] testFulfillRandomWordsAndPickWinnerAndSendMoney() (gas: 369870)
[PASS] testLotteryInLiveDuration() (gas: 13050)
[PASS] testLotteryInitializesInOpenState() (gas: 13178)
[PASS] testLotteryInitializesWithCorrectCallbackGasLimit() (gas: 13127)
[PASS] testLotteryInitializesWithCorrectEntranceFee() (gas: 13017)
[PASS] testLotteryInitializesWithCorrectGasLane() (gas: 13138)
[PASS] testLotteryInitializesWithCorrectRequestConfirmations() (gas: 13054)
[PASS] testLotteryRevertWhenYouDontPayEnoughEntranceFee() (gas: 22350)
[PASS] testLotteryRevertWhenYouDontPayEntranceFee() (gas: 13481)
[PASS] testLotterySavesPlayerWhenTheyEnter() (gas: 68623)
[PASS] testPerformUpKeepEmitsRequestId() (gas: 217341)
[PASS] testPerformUpKeepIfCheckUpKeepReturnsTrueUpdatesState() (gas: 214780)
[PASS] testRevertPerformUpKeepIfCheckUpKeepReturnsFalse() (gas: 72591)
Suite result: ok. 21 passed; 0 failed; 0 skipped; finished in 24.73ms (35.48ms CPU time)

Ran 1 test suite in 27.21ms (24.73ms CPU time): 21 tests passed, 0 failed, 0 skipped (21 total tests)

output of error

forge script script/DeployLottery.s.sol:DeployLottery --rpc-url http://localhost:8545 --account Account1 --broadcast
[⠒] Compiling...
No files changed, compilation skipped
0x4e487b710000000000000000000000000000000000000000000000000000000000000011
EIP-3855 is not supported in one or more of the RPCs used.
Unsupported Chain IDs: 31337.
Contracts deployed with a Solidity version equal or higher than 0.8.20 might not work properly.
For more information, please see https://eips.ethereum.org/EIPS/eip-3855
Traces:
  [21607918] → new DeployLottery@0x5b73C5498c1E3b4dbA84de0F1833c4a029d90519
    └─ ← [Return] 107717 bytes of code

  [13285645] DeployLottery::run()
    ├─ [4501993] → new HelperConfig@0xC7f2Cf4845C6db0e1a1e91ED41Bcd0FcC1b0E141
    │   └─ ← [Return] 21407 bytes of code
    ├─ [3822626] HelperConfig::getConfig()
    │   ├─ [746241] → new LinkToken@0x7AaCc5300ec7Ac58fe86645D08f21b1BEcadf99a
    │   │   ├─ emit Transfer(from: 0x0000000000000000000000000000000000000000, to: HelperConfig: [0xC7f2Cf4845C6db0e1a1e91ED41Bcd0FcC1b0E141], amount: 1000000000000000000000000 [1e24])
    │   │   └─ ← [Return] 3267 bytes of code
    │   ├─ [0] VM::startBroadcast(DefaultSender: [0x1804c8AB1F12E6bbf3894d4083f33e07309d1f38])
    │   │   └─ ← [Return] 
    │   ├─ [2863541] → new VRFCoordinatorV2_5Mock@0x34A1D3fff3958843C43aD80F30b94c510645C316
    │   │   ├─ emit ConfigSet()
    │   │   └─ ← [Return] 13951 bytes of code
    │   ├─ [0] VM::stopBroadcast()
    │   │   └─ ← [Return] 
    │   └─ ← [Return] NetworkConfig({ entranceFee: 10000000000000000 [1e16], lotteryDuration: 30, vrfCoordinator: 0x34A1D3fff3958843C43aD80F30b94c510645C316, gasLane: 0x474e34a077df58807dbe9c96d3c009b23b3c6d0cce433e59bbf5b34f823bc56c, subscriptionId: 0, requestConfirmations: 4, callbackGasLimit: 500000 [5e5], linkTokenAddress: 0x7AaCc5300ec7Ac58fe86645D08f21b1BEcadf99a, account: 0x1804c8AB1F12E6bbf3894d4083f33e07309d1f38 })
    ├─ [4880454] → new CreateSubscription@0xdaE97900D4B184c5D2012dcdB658c008966466DD
    │   └─ ← [Return] 24263 bytes of code
    ├─ [6957] CreateSubscription::createSubscription(VRFCoordinatorV2_5Mock: [0x34A1D3fff3958843C43aD80F30b94c510645C316], DefaultSender: [0x1804c8AB1F12E6bbf3894d4083f33e07309d1f38])
    │   ├─ [0] console::log("Creating a subscription on ChainId:", 31337 [3.133e4], DefaultSender: [0x1804c8AB1F12E6bbf3894d4083f33e07309d1f38]) [staticcall]
    │   │   └─ ← [Stop] 
    │   ├─ [0] VM::startBroadcast(DefaultSender: [0x1804c8AB1F12E6bbf3894d4083f33e07309d1f38])
    │   │   └─ ← [Return] 
    │   ├─ [2616] VRFCoordinatorV2_5Mock::createSubscription()
    │   │   └─ ← [Revert] panic: arithmetic underflow or overflow (0x11)
    │   └─ ← [Revert] panic: arithmetic underflow or overflow (0x11)
    └─ ← [Revert] panic: arithmetic underflow or overflow (0x11)



== Logs ==
  Creating a subscription on ChainId: 31337 0x1804c8AB1F12E6bbf3894d4083f33e07309d1f38
Error: 
script failed: panic: arithmetic underflow or overflow (0x11)
make: *** [Makefile:34: deploy-anvil] Error 1

[EngrPips]

I meant the deployment script lol, sorry about that.

[EngrPips]

@saikrishna5907, In the output, when it creates a subscription for me, I have the below

 ├─ [52618] CreateSubscription::createSubscription(VRFCoordinatorV2PlusMock: [0x0165878A594ca255338adfa4d48449f69242Eb8F], 77814517325470205911140941194401928579557062014761831930645393041380819009408 [7.781e76])

But for you, it shows the below.

├─ [6957] CreateSubscription::createSubscription(VRFCoordinatorV2_5Mock: [0x34A1D3fff3958843C43aD80F30b94c510645C316], DefaultSender: [0x1804c8AB1F12E6bbf3894d4083f33e07309d1f38])

The bottom line is for your deployment process: when you called createSubscription, you called the function with a VRFCoordinatorV2_5Mock address and an address instead of passing in a privateKey. Can you figure out why is that?