ChainID get set to Base testnet when only Base mainnet is passed into createWagmiConfig

[blmalone]

Check existing issues

• [X] I checked there isn't already an issue for the bug I encountered.

Describe the bug

Inconsistent behavior when you pass through networks to the create config functionality.

Link to Minimal Reproducible Example

No response

Steps To Reproduce

Step to reproduce:

Using this configuration will return the Base testnet chainId instead of Base mainnet.

import { createConfig, http } from 'wagmi';
import { base } from 'wagmi/chains';
import { coinbaseWallet } from 'wagmi/connectors';

export function createWagmiConfig(rpcUrl: string, projectId?: string) {
  // Keep this till we fully deprecated RK inside the template
  if (projectId) {
    console.log('projectId:', projectId);
  }

  // Temporary hack, until we configure a FE page in OnchainKit to copy just the API key
  const baseUrl = rpcUrl.replace(/\/v1\/(.+?)\//, '/v1/base/');

  return createConfig({
    chains: [base],
    connectors: [
      coinbaseWallet({
        appName: '0xCafeBabe',
        preference: 'all', // Setting this as all gives you the QR code for scanning with Coinbase wallet.
      }),
    ],
    ssr: true,
    transports: {
      [base.id]: http(baseUrl),
    },
  });
}

To fix it, you need to pass through both networks to the config.

import { createConfig, http } from 'wagmi';
import { base, baseSepolia } from 'wagmi/chains';
import { coinbaseWallet } from 'wagmi/connectors';

export function createWagmiConfig(rpcUrl: string, projectId?: string) {
  // Keep this till we fully deprecated RK inside the template
  if (projectId) {
    console.log('projectId:', projectId);
  }

  // Temporary hack, until we configure a FE page in OnchainKit to copy just the API key
  const baseUrl = rpcUrl.replace(/\/v1\/(.+?)\//, '/v1/base/');
  const baseSepoliaUrl = rpcUrl.replace(/\/v1\/(.+?)\//, '/v1/base-sepolia/');

  return createConfig({
    chains: [base, baseSepolia],
    connectors: [
      coinbaseWallet({
        appName: '0xCafeBabe',
        preference: 'all', // Setting this as all gives you the QR code for scanning with Coinbase wallet.
      }),
    ],
    ssr: true,
    transports: {
      [baseSepolia.id]: http(baseSepoliaUrl),
      [base.id]: http(baseUrl),
    },
  });
}

What Wagmi package(s) are you using?

wagmi

Wagmi Version

^2.9.2

Viem Version

2.16.1

TypeScript Version

~5.3.3

Anything else?

No response

[blmalone]

@oliviabarnett

[github-actions[bot]]

Hello @blmalone.

Please provide a minimal reproduction using StackBlitz, TypeScript Playground (for type issues), or a separate minimal GitHub repository.

Minimal reproductions are required as they save us a lot of time reproducing your config/environment and issue, and allow us to help you faster.

Once a minimal reproduction is added, a team member will confirm it works, then re-open the issue.