Very weird [FAIL. Reason: EvmError: Revert], only when test with USDT ERC20.

[KuangyeChen]

Component

Forge

Have you ensured that all of these are up to date?

• Foundry
• Foundryup

What version of Foundry are you on?

forge 0.2.0 (d7d2901 2023-11-29T00:16:36.235049762Z)

What command(s) is the bug in?

forge test --rpc-url ${MAINNET_URL}

Operating System

macOS (Intel)

Describe the bug

Here is the code I have tested. If the token address is USDT, the test will fail with: [FAIL. Reason: EvmError: Revert]. I have tested with DAI and WETH, it will pass. It's the same on Linux and on Intel Mac. I don't know if there are other ERC20 contracts that will trigger the revert.

But since USDT is kinda important, I issue this here.

function testFoo() public {
    ERC20 token = ERC20(0xdAC17F958D2ee523a2206206994597C13D831ec7);
    token.approve(
        uniswapV2AddressBook.uniswapV2Router02,
        2 ** 256 - 1 - 100
    );
}

The error:

  [32142] TestUniswapToleranceCheck::testFoo()
    ├─ [26953] 0xdAC17F958D2ee523a2206206994597C13D831ec7::approve(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D, 115792089237316195423570985008687907853269984665640564039457584007913129639835 [1.157e77])
    │   ├─ emit Approval(owner: TestUniswapToleranceCheck: [0x7FA9385bE102ac3EAc297483Dd6233D62b3e1496], spender: 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D, value: 115792089237316195423570985008687907853269984665640564039457584007913129639835 [1.157e77])
    │   └─ ← ()
    └─ ← EvmError: Revert

[jubeira]

@KuangyeChen use safeApprove ser: https://forum.openzeppelin.com/t/can-not-call-the-function-approve-of-the-usdt-contract/2130/2

[KuangyeChen]

@KuangyeChen use safeApprove ser: https://forum.openzeppelin.com/t/can-not-call-the-function-approve-of-the-usdt-contract/2130/2

Interesting, didn't know that.

[KuangyeChen]

safeApprove is deprecated according to this issue. Use safeIncreaseAllowance instead.

[jubeira]

Yeah right, or force approve: https://docs.openzeppelin.com/contracts/4.x/api/token/erc20#SafeERC20-forceApprove-contract-IERC20-address-uint256-. Same concept.