TX.wait() never resolves even though the transaction has already been completed.

[Suvanch]

Ethers Version

6.6.2

Search Terms

No response

Describe the Problem

TX.wait() never resolves even though the transaction has already been completed. I am using ethers.js 6.2 and hardhat to test my code. This is my code.

const routerContract = new hre.ethers.Contract(
    router,
    [
        'function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline) external payable returns (uint[] memory amounts)'
    ],
    signer
);

const swapTx =  await routerContract.swapExactETHForTokens(
    amountOutMin,
    [WETH, token_address],
    ME,
    Date.now() + 1000 * 60 * 10,
    {'value': ETHAmountIn,"gasPrice": gasPrice, "gasLimit": gasLimit}
)
//console.log(swapTx);
let receipt = await swapTx.wait();

When I run this code, the hardhat shows the transaction has already been completed. And in the wallet, I can see the swap has happed correctly.

eth_sendRawTransaction
  Contract call:   <UnrecognizedContract>
  Transaction:     0x499d04cf2afef112c1715b7821131873a2e5475080ad20f262dda9a65b5c9864
  From:            0xf39fd6e51aad88f6f4ce6ab8827279cfffb92266
  To:              0x7a250d5630b4cf539739df2c5dacb4c659f2488d
  Value:           1 ETH
  Gas used:        157884 of 221283
  Block #17664625: 0x8d2d257060ec0bc0b0a8fbf71a1bc2cb99eaabbf6d0a2c27f8bb0b7909db99af

eth_chainId (2)
eth_getTransactionReceipt
eth_chainId
eth_subscribe

I have already tried increasing gas and tried getting the receipt through the provider like... But I am still unable to get the receipt
let reciept = await provider.waitForTransaction(swapTx.hash, 1)

I don't really know what else to do so any help would be much appreciated.

Code Snippet

No response

Contract ABI

No response

Errors

No response

Environment

node.js (v12 or newer), Hardhat

Environment (Other)

No response

[wighawag]

I noticed a similar issue

the context is using ethers v6 in hardhat test where in most case hardhat auto-mining is enabled and where once you get a tx hash you know you can get the receipt straigthaway

with ethers v6 unfortunately it seems that the receipt cannot be fetched directly

I can workaround by changing this line:

ethers.js/src.ts/providers/provider.ts

Line 1466 in 1dd5427

if ((await receipt.confirmations()) >= confirms) { return receipt; }

to always return if confirrns === 0 . this is because in some case the confirmations() return -1

[wighawag]

I can actually make it work by using tx.wait(Number.MIN_SAFE_INTEGER) but feel like using confirmations == 0 should work here

[Suvanch]

I change my code to look like this but I still have the same problem.

let receipt = await swapTx.wait(Number.MIN_SAFE_INTEGER);

I also tried it like this

let receipt = await swapTx.wait(0);

Am I doing something wrong?

[ricmoo]

There should definitely not be any case where you have -1 confirmations. And MIN_SAFE_INTEGER really doesn’t make sense..

I have to look more into this. Can you include how you create the provider and signer?

[Suvanch]

const provider = new ethers.WebSocketProvider("ws://127.0.0.1:8545/");

const wallet = new hre.ethers.Wallet("0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80");
const signer = wallet.connect(provider);

The Private key is the first wallet created by Hardhat.

[tcrbn]

@ricmoo
This appears to be caused by a race condition in the wait function.

The condition happens when the transaction is committed after the call to getTransactionReceipt https://github.com/ethers-io/ethers.js/blob/main/src.ts/providers/provider.ts#L1596 and before the call to checkReplacement https://github.com/ethers-io/ethers.js/blob/main/src.ts/providers/provider.ts#L1607

If this happens and there is no new block mined after this, then the wait will be stuck forever, as the checkReplacement will expect the transaction not to be committed up to this block.

You can likely reproduce this condition more reliably by adding a sleep for example here to allow the block to be mined with the transaction https://github.com/ethers-io/ethers.js/blob/main/src.ts/providers/provider.ts#L1608