hardhat command evaluates `hardhat.config.ts` for system commands like `keystore`

[michalbrabec]

Feedback

I set an account in keystore to an invalid value (prefix 0x was missing)
When I try to run npx hardhat keystore set OP_SENDER --force to update it, I get

Error HHE15: Invalid config:
        * Config error in config.networks.op.accounts.0: Expected a hex-encoded private key or a Configuration Variable

It evaluates the hardhat.config.ts even for keystore commands and help
Not sure if this can be avoided without significant redesign, but it makes it difficult to fix the value once set to invalid

The hardhat.config.ts is the default from v-next (https://github.com/NomicFoundation/hardhat/blob/v-next/v-next/example-project/hardhat.config.ts), but the config var OP_SENDERis not set, which results in invalid networks configuration.

Repro Steps

• git clone -b v-next https://github.com/NomicFoundation/hardhat.git
• cd hardhat
• pnpm i
• pnpm build
• cd v-next/example-project
• change the hardhat.config.ts
  • replace line 121 with accounts: ['configVariable("OP_SENDER")'], (add quotes around the variable)
• npx hardhat keystore set OP_SENDER --force

[michalbrabec]

Same issue is present in HH2

hardhat.config.ts

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

const config: HardhatUserConfig = {
  solidity: "0.8.28",
  networks: {
    op: {
      url: "https://mainnet.optimism.io/",
      accounts: ['configVariable("OP_SENDER")'],
    },
  }
};

export default config;

Result of npx hardhat keystore set

Error HH8: There's one or more errors in your config file:

  * Invalid account: #0 for network: op - private key too short, expected 32 bytes

To learn more about Hardhat's configuration, please go to https://hardhat.org/config/

For more info go to https://hardhat.org/HH8 or run Hardhat with --show-stack-traces

This is expected and it is a limitation of V2 architecture - won't fix

[michalbrabec]

All tasks require the hardhat.config.json to be valid since it is needed to identify user-defined tasks and options. It is needed to run most tasks and required even for help (to list the user-refined tasks).

We decided to keep the existing logic and make HHE15 error more descriptive to explain that the config is needed and why. The proposed test of the error is:

Hardhat requires a valid hardhat.config.ts file to identify and execute all tasks. 
Hardhat couldn't run because the configuration is invalid:

Further separation of tasks that do not need the config is on the roadmap