Defi StableCoin: Assertion failed when running Invariants test

[ajoomye]

Hello, I am getting this "[FAIL: failed to set up invariant testing environment: panic: assertion failed (0x01)]" error when running the "Protocol must have more than Total Supply Test".

The full error when I run -vvvv is as follows:

Ran 1 test for test/fuzz/OpenInvariantsTest.t.sol:InvariantTests
[FAIL: failed to set up invariant testing environment: panic: assertion failed (0x01)] invariant_protocolMustHaveMoreValuethanTotSupply() (runs: 0, calls: 0, reverts: 0)
Traces:
  [10232247] InvariantTests::setUp()
    ├─ [4564408] → new DeployDSC@0x5615dEB798BB3E4dFa0139dFa1b3D433Cc23b72f
    │   └─ ← [Return] 22685 bytes of code
    ├─ [5466137] DeployDSC::run()
    │   ├─ [3647184] → new HelperConfig@0x104fBc016F4bb334D775a19E8A6510109AC63E00
    │   │   ├─ [0] VM::startBroadcast()
    │   │   │   └─ ← [Return] 
    │   │   ├─ [362441] → new MockV3Aggregator@0x34A1D3fff3958843C43aD80F30b94c510645C316
    │   │   │   └─ ← [Return] 1033 bytes of code
    │   │   ├─ [362441] → new MockV3Aggregator@0x90193C961A926261B756D1E5bb255e67ff9498A1
    │   │   │   └─ ← [Return] 1033 bytes of code
    │   │   ├─ [646061] → new ERC20Mock@0xA8452Ec99ce0C64f20701dB7dD3abDb607c00496
    │   │   │   ├─ emit Transfer(from: 0x0000000000000000000000000000000000000000, to: DeployDSC: [0x5615dEB798BB3E4dFa0139dFa1b3D433Cc23b72f], value: 100000000000 [1e11])
    │   │   │   └─ ← [Return] 2766 bytes of code
    │   │   ├─ [646061] → new ERC20Mock@0xBb2180ebd78ce97360503434eD37fcf4a1Df61c3
    │   │   │   ├─ emit Transfer(from: 0x0000000000000000000000000000000000000000, to: DeployDSC: [0x5615dEB798BB3E4dFa0139dFa1b3D433Cc23b72f], value: 100000000000 [1e11])
    │   │   │   └─ ← [Return] 2766 bytes of code
    │   │   ├─ [0] VM::stopBroadcast()
    │   │   │   └─ ← [Return] 
    │   │   └─ ← [Return] 6697 bytes of code
    │   ├─ [911] HelperConfig::activeNetworkConfig() [staticcall]
    │   │   └─ ← [Return] MockV3Aggregator: [0x34A1D3fff3958843C43aD80F30b94c510645C316], MockV3Aggregator: [0x90193C961A926261B756D1E5bb255e67ff9498A1], ERC20Mock: [0xA8452Ec99ce0C64f20701dB7dD3abDb607c00496], ERC20Mock: [0xBb2180ebd78ce97360503434eD37fcf4a1Df61c3], 77814517325470205911140941194401928579557062014761831930645393041380819009408 [7.781e76]
    │   ├─ [0] VM::startBroadcast(<pk>)
    │   │   └─ ← [Return] 
    │   ├─ [735993] → new DecentralizedStableCoin@0x5FbDB2315678afecb367f032d93F642f64180aa3
    │   │   ├─ emit OwnershipTransferred(previousOwner: 0x0000000000000000000000000000000000000000, newOwner: 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266)
    │   │   └─ ← [Return] 3332 bytes of code
    │   ├─ [841021] → new DSCEngine@0xe7f1725E7734CE288F8367e1Bb143E90bb3F0512
    │   │   └─ ← [Return] 3523 bytes of code
    │   ├─ [2443] DecentralizedStableCoin::transferOwnership(DSCEngine: [0xe7f1725E7734CE288F8367e1Bb143E90bb3F0512])
    │   │   ├─ emit OwnershipTransferred(previousOwner: 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266, newOwner: DSCEngine: [0xe7f1725E7734CE288F8367e1Bb143E90bb3F0512])
    │   │   └─ ← [Stop] 
    │   ├─ [0] VM::stopBroadcast()
    │   │   └─ ← [Return] 
    │   └─ ← [Return] DecentralizedStableCoin: [0x5FbDB2315678afecb367f032d93F642f64180aa3], DSCEngine: [0xe7f1725E7734CE288F8367e1Bb143E90bb3F0512], HelperConfig: [0x104fBc016F4bb334D775a19E8A6510109AC63E00]
    ├─ [911] HelperConfig::activeNetworkConfig() [staticcall]
    │   └─ ← [Return] MockV3Aggregator: [0x34A1D3fff3958843C43aD80F30b94c510645C316], MockV3Aggregator: [0x90193C961A926261B756D1E5bb255e67ff9498A1], ERC20Mock: [0xA8452Ec99ce0C64f20701dB7dD3abDb607c00496], ERC20Mock: [0xBb2180ebd78ce97360503434eD37fcf4a1Df61c3], 77814517325470205911140941194401928579557062014761831930645393041380819009408 [7.781e76]
    └─ ← [Stop] 

Suite result: FAILED. 0 passed; 1 failed; 0 skipped; finished in 6.28ms (2.76ms CPU time)

Ran 1 test suite in 1.27s (6.28ms CPU time): 0 tests passed, 1 failed, 0 skipped (1 total tests)

Failing tests:
Encountered 1 failing test in test/fuzz/OpenInvariantsTest.t.sol:InvariantTests
[FAIL: failed to set up invariant testing environment: panic: assertion failed (0x01)] invariant_protocolMustHaveMoreValuethanTotSupply() (runs: 0, calls: 0, reverts: 0)

Encountered a total of 1 failing tests, 0 tests succeeded

My OpenInvariantsTest.t.sol is as follows:

//Invariants:
// Total number of DSC should be less than the total collateral
// Getter view functions should never revert


// SPDX-License-Identifier: MIT
pragma solidity 0.8.28;

import {DecentralizedStableCoin} from "src/DecentralizedStableCoin.sol";
import {DSCEngine} from "src/DSCEngine.sol";
import {Test, console} from "forge-std/Test.sol";
import {DeployDSC} from "script/DeployDSC.s.sol";
import {HelperConfig} from "script/HelperConfig.s.sol";
import {StdInvariant} from "forge-std/StdInvariant.sol";
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";

contract InvariantTests is StdInvariant, Test {
    DeployDSC public deployDSC;
    DSCEngine public dscEngine;
    HelperConfig config;
    DecentralizedStableCoin public dsc;
    address weth;
    address wbtc;

    function setUp() external {
        deployDSC = new DeployDSC();
        (dsc, dscEngine, config) = deployDSC.run();
        ( , , weth, wbtc, ) = config.activeNetworkConfig();
        targetContract(address(dscEngine));
    }

    function invariant_protocolMustHaveMoreValuethanTotalSupply() public view {
        uint256 totalSupply = dsc.totalSupply();
        uint256 totalWeth = IERC20(weth).balanceOf(address(dscEngine));
        uint256 totalWbtc = IERC20(wbtc).balanceOf(address(dscEngine));

        uint256 wethValue = dscEngine.getUsdValue(weth, totalWeth);
        uint256 wbtcValue = dscEngine.getUsdValue(wbtc, totalWbtc);

        console.log("Total Supply:", totalSupply);
        console.log("WETH Value:", wethValue);
        console.log("WBTC Value:", wbtcValue);

        assert(wethValue + wbtcValue > totalSupply);
    }

}

I have run foundryup and forge clean as suggested by a previous discussion but I get the same issues. The unit tests are working perfectly. Kindly help, Thank you.

[EngrPips]

Hello, sir @PatrickAlphaC. Your insight will be greatly appreciated as this is the second person running into this kind of error, and I haven't been able to pinpoint the issue.

[jprabhat]

Hey, @ajoomye I also got this issue but gets resolved by putting these in foundary.toml

[invariant]
runs = 1000
depth = 128
fail_on_revert = false

as we increased runs value to 1000 the setup gets completed and test passes successfully!
hope this will help you

[KMean]

Thanks, unfortunately. I have the same issue

change

assert(wethValue + wbtcValue > totalSupply);

to

assert(wethValue + wbtcValue >= totalSupply);

[EngrPips]

Interesting.

[ajoomye]

Thanks, unfortunately. I have the same issue

change

assert(wethValue + wbtcValue > totalSupply);

to

assert(wethValue + wbtcValue >= totalSupply);

This works. Thanks a lot. Any idea why it does though?

[EngrPips]

🤔

[KMean]

Thanks, unfortunately. I have the same issue

change

assert(wethValue + wbtcValue > totalSupply);

to

assert(wethValue + wbtcValue >= totalSupply);

This works. Thanks a lot. Any idea why it does though?

because if weth and wbtc are 0

 assert(wethValue + wbtcValue > totalSupply);

will fail. In fact if you do something like this for example

function invariant_openProtocolMustHaveMoreValueThanTotalSupply() public view {
        console2.log("invariant_openProtocolMustHaveMoreValueThanTotalSupply");
        //get the value of all the collateral in the protocol
        //compare it to the total supply of the dsc (debt)
        uint256 totalSupply = dsc.totalSupply();
        console2.log("totalSupply: ", totalSupply);
        uint256 totalWethDeposited = IERC20(weth).balanceOf(address(engine));
        uint256 totalWbtcDeposited = IERC20(wbtc).balanceOf(address(engine));

        uint256 wethValue = engine.getUsdValue(weth, totalWethDeposited);
        uint256 wbtcValue = engine.getUsdValue(wbtc, totalWbtcDeposited);
        wethValue = 1 ether;
        console2.log("wethValue: ", wethValue);
        console2.log("wbtcValue: ", wbtcValue);

        assert(wethValue + wbtcValue > totalSupply);
    }

It will pass.

assert(wethValue + wbtcValue >= totalSupply);

This is not ideal as we would like to be overcollaterized hence the name MustHaveMoreValueThanTotalSupply. By doing >= we are saying that the amount of collateral can be equal to the total supply of dsc. That's why later in the course we are creating Handlers to deal with this kind of situations.