Error when I try to run test forked from Arbitrum network

[AbigailTCameron]

I've been trying to run tests, npx hardhat test on the arbitrum network with the basic testing framework that hardhat establishes upon creating a new project and I am continuously met with this error:

OnlyHardhatNetworkError: This helper can only be used with Hardhat Network. You are connected to 'hardhat'.
at checkIfHardhatNetwork (/Users/abigailcameron/testing-arb/node_modules/@nomicfoundation/hardhat-network-helpers/src/utils.ts:28:11)
      at getHardhatProvider (/Users/abigailcameron/testing-arb/node_modules/@nomicfoundation/hardhat-network-helpers/src/utils.ts:39:9)
      at async Object.latest (/Users/abigailcameron/testing-arb/node_modules/@nomicfoundation/hardhat-network-helpers/src/helpers/time/latest.ts:7:20)
      at async Context.<anonymous> (/Users/abigailcameron/testing-arb/test/Lock.ts:51:26)
An unexpected error occurred:

InternalError: Unknown transaction type 106
at ForkBlockchain._processRemoteBlock (/Users/abigailcameron/testing-arb/node_modules/hardhat/src/internal/hardhat-network/provider/fork/ForkBlockchain.ts:300:15)
    at ForkBlockchain._getBlockByNumber (/Users/abigailcameron/testing-arb/node_modules/hardhat/src/internal/hardhat-network/provider/fork/ForkBlockchain.ts:242:17)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async ForkBlockchain.getBlock (/Users/abigailcameron/testing-arb/node_modules/hardhat/src/internal/hardhat-network/provider/fork/ForkBlockchain.ts:66:13)
    at async ForkBlockchain.getLatestBlock (/Users/abigailcameron/testing-arb/node_modules/hardhat/src/internal/hardhat-network/provider/BlockchainBase.ts:87:19)
    at async Function.create (/Users/abigailcameron/testing-arb/node_modules/hardhat/src/internal/hardhat-network/provider/node.ts:205:31)
    at async HardhatNetworkProvider._init (/Users/abigailcameron/testing-arb/node_modules/hardhat/src/internal/hardhat-network/provider/provider.ts:251:28)
    at async HardhatNetworkProvider._send (/Users/abigailcameron/testing-arb/node_modules/hardhat/src/internal/hardhat-network/provider/provider.ts:192:5)
    at async HardhatNetworkProvider.request (/Users/abigailcameron/testing-arb/node_modules/hardhat/src/internal/hardhat-network/provider/provider.ts:118:18)
    at async SimpleTaskDefinition.action (/Users/abigailcameron/testing-arb/node_modules/hardhat/src/builtin-tasks/test.ts:171:37)
abigailcameron@MacBook-Pro testing-arb % 

The only changes I have made were done to the hardhat.config.ts file so that we're forking from the arbitrum network

import { HardhatUserConfig } from "hardhat/config";
import "@nomicfoundation/hardhat-toolbox";

const config: HardhatUserConfig = {
  solidity: "0.8.17",
  networks:{
    hardhat:{
      chainId: 42161,
      forking:{
        url: "https://arb1.arbitrum.io/rpc"
      }
    }
  }
};

export default config;

I've already tried running hardhat patch but that doesn't seem to work for me, and I ONLY get this error when I try forking from the arbitrum network.

N.B. I am running the latest hardhat version to date (^2.11.2).

[github-actions]

This issue is also being tracked on Linear.

We use Linear to manage our development process, but we keep the conversations on Github.

LINEAR-ID: 11941d78-8527-444a-8c6c-a16a13590a0d

[voytenko-d]

The problem with new blocks, in my case, using old blocks helped me. When forking a branch, try not to start from the latest blocks.

networks: {
    hardhat: {
      forking: {
        url: `https://***/${process.env.***}`,
        blockNumber: 20005467
      },
    },
  },

[AbigailTCameron]

That doesn't work for me, I still get the same OnlyHardhatNetworkError: This helper can only be used with Hardhat Network. You are connected to 'hardhat'. error

[fvictorio]

I think the underlying cause here is the same as in #2995

The reason is that when forking starts, the latest block is fetched and processed. If that block has txs with "unknown" types, then the fork initialization fails. In this case, since the initialization is triggered by a network helper, then we are (incorrectly) assuming that it failed because of a non-hardhat network.

In short:

• We need to figure out what to do about Add flag to ignore unknown EIP-2718 types when forking #2995
• We need to show a better error when the hardhat check failed because of an error and not because the returned web3_version was from a non-hardhat network.

[fvictorio]

Hi, we just published a beta version of Hardhat that should fix the forking issue. I would appreciate it if you can give it a try:

npm install hardhat@unknown-txs

(If you are using npm 7 or later, you might get some warnings about unsatisfied peer dependencies, but you can ignore those.)

If this seems to be working fine, we'll publish a stable version with this change as soon as possible.

Please try it out and let us know if it works (or doesn't!)

[branzinho]

I am also getting this issue when connecting to goerli.
OnlyHardhatNetworkError: This helper can only be used with Hardhat Network. You are connected to 'goerli', whose identifier is 'Geth/v1.10.23-stable-d901d853/linux-amd64/go1.18.5'

[Skyge]

@branzinho-nt I think you use something from @nomicfoundation/hardhat-network-helpers, such as loadFixture.

[fvictorio]

This fix is now included in the latest release.