Bug Report

Cairo version: 8a160d3d7c00f7abada689cb3fbc1bb6daba072b

Current behavior: When running cairo-test --starknet ., the test runner fails with error

Error: Failed setting up runner.

Caused by:
    Failed calculating gas usage, it is likely a call for `gas::withdraw_gas` is missing.

It’s very weird, because it doesn’t happen everytime. I’m writing tests against deployed contracts, using the following code:

use starknet::syscalls::deploy_syscall;
use starknet::class_hash::Felt252TryIntoClassHash;
use starknet::contract_address::contract_address_const;
use starknet::ContractAddress;
use starknet::testing;
use starknet::get_contract_address;
use traits::Into;
use traits::TryInto;
use option::OptionTrait;
use result::ResultTrait;
use array::ArrayTrait;
use debug::PrintTrait;


use simple_vault::vault::Vault;
use simple_vault::vault::IVaultDispatcher;
use simple_vault::vault::IVaultDispatcherTrait;
use tests::mocks::mock_erc20::MockERC20;
use tests::mocks::mock_erc20::IMockERC20Dispatcher;
use tests::mocks::mock_erc20::IMockERC20DispatcherTrait;
use openzeppelin::token::erc20::IERC20Dispatcher;
use openzeppelin::token::erc20::IERC20DispatcherTrait;

fn setup() -> (IMockERC20Dispatcher, IVaultDispatcher) {
    // Set up.

    // Deploy mock token.

    let user1 = contract_address_const::<0x123456789>();

    let mut calldata = ArrayTrait::new();
    let name = 'Mock Token';
    let symbol = 'TKN';
    calldata.append(name);
    calldata.append(symbol);

    let (token_address, _) = deploy_syscall(
        MockERC20::TEST_CLASS_HASH.try_into().unwrap(), 0, calldata.span(), false
    ).unwrap();

    let mut calldata = ArrayTrait::<felt252>::new();
    calldata.append('Mock Token Vault');
    calldata.append('vwTKN');
    calldata.append(token_address.into());
    let (vault_address, _) = deploy_syscall(
        Vault::TEST_CLASS_HASH.try_into().unwrap(), 0, calldata.span(), false
    ).unwrap();

    let token = IMockERC20Dispatcher { contract_address: token_address };
    let vault = IVaultDispatcher { contract_address: vault_address };

    (token, vault)
}

#[test]
#[available_gas(2000000000000)]
fn test_atomic_deposit_withdratest_atomic_deposit_withdraww() {
    let (underlying, vault) = setup();
    let alice = contract_address_const::<0x123456789>();
    testing::set_contract_address(alice);
    underlying.mint(alice, 100.into());
    // //TODO fix: calling underlying.approve() here causes a failed calculating gas usage here
    underlying.approve(vault.contract_address, 100.into());

   //  snip
}

I haven’t been able to isolate the problem, as it worked fine when I used tried to setup a smaller repo with just ERC20 + testing mocks for mint/approval. I can provide more context with the full repository if required, but it’s changing constantly and subject to a lot of changes. Expected behavior: The test runs fine

Steps to reproduce:

Other information:

Halfway through redacting this, I actually re-tested to see what happened when I uncommented the underlying.approve(vault.contract_address, 100.into());, and it ran; but after removing the TODO comment above, it stopped running. This non-determinism is quite odd 🤔 . I can’t figure out how to reproduce it reliably. The code and its dependencies don’t rely on any recursive function or loop.

The non-determinism is the most surprising part, as randomly commenting - uncommenting lines seems to fix it for a while, before modifying the file again and breaking it.