hardhat-verify support for L2 testnets

[michalinacienciala]

Describe the feature

As Goerli testnet deprecates with the end of the year, a lot of L2 networks change their testnets from Goerli-based to Sepolia-based. Along with those changes, the scan websites also add the support for Sepolia-based L2 testnets. But so far hardhat-verify does not include those new chains in https://github.com/NomicFoundation/hardhat/blob/main/packages/hardhat-verify/src/internal/chain-config.ts, which I think means that hardhat-verify will not work for them.
Here are some L2 testnets I would like to see supported:

• Arbitrum Sepolia (id 421614) - https://sepolia.arbiscan.io/ (already tracked in hardhat-verify support for Arbitrum Sepolia testnet as main testnet for Arbitrum #4582)
• Base Sepolia (id 84532) - ArbiScan does not support it yet, but I got a following info from them about the support: 'At this point, Base Sepolia is already in the pipeline but there is no estimation when can we push the site to live. Stay tuned for more info and make sure to follow BaseScan's Twitter to yourself updated when it is already live.'
• Optimism Sepolia (id 11155420) - https://sepolia-optimism.etherscan.io/

Search terms

hardhard-verify sepolia arbitrumSepolia baseSepolia optimisticSepolia

[michalinacienciala]

Btw, the Mumbai testnet is also planned to be deprecated and replaced by the Amoy testnet (name: amoy, chain id: 80002). Not sure when will that happen and when will the polygonscan support it.
Read more:
maticnetwork/heimdall#1096
maticnetwork/bor#1072

[jacek0x]

It would be cool if Base Sepolia were supported.

[schaable]

Btw, until these networks are added to the chain list, you can still verify contracts by adding them to your hardhat config as custom chains, for example:

etherscan: {
  apiKey: {
    optimismSepolia: "<optimism-sepolia-api-key>"
  },
  customChains: [
    {
      network: "optimismSepolia",
      chainId: 11155420,
      urls: {
        apiURL: "https://api-sepolia-optimistic.etherscan.io/api",
        browserURL: "https://sepolia-optimism.etherscan.io/"
      }
    }
  ]
}

You can read more here.

[jacek0x]

@schaable Awesome, thanks! That worked.

[tazous]

Btw, the Mumbai testnet is also planned to be deprecated and replaced by the Amoy testnet (name: amoy, chain id: 80002). Not sure when will that happen and when will the polygonscan support it. Read more: maticnetwork/heimdall#1096 maticnetwork/bor#1072

It seems that amoy block explorer won't be polygonscan but oklink as refered here: https://polygon.technology/blog/introducing-the-amoy-testnet-for-polygon-pos
Is there a plan for this plugin to support oklink block explorer as a source verifier api to target ? (the same way sourcify was added)... I found this project if it is helping: https://github.com/enjinstarter/hardhat-oklink-verify/tree/main/src but I would be more confident in using an hardhat supported plugin inside my production environment...

[iPaulPro]

Goerli is down and https://amoy.polygonscan.com/ is up. Any eta on this?

[schaable]

Amoy has been added to the chain list in hardhat-verify and will be available on the next release of the plugin: #5163