fix(vite): ignore and warn if vite config file exists

[NozomuIkuta]

🔗 Linked issue

Resolves #21553

❓ Type of change

• 📖 Documentation (updates to the documentation, readme or JSdoc annotations)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

This PR is created based on #21553 (comment).

We can let Vite ignore its config file when calling build() and createServer() by setting configFile: false.

I tested my logic by adding vite.config.js to playground directory and run pnpm -w run play:build to check if the warning message is shown.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

Should I add some information to docs?

[NozomuIkuta]

Here, we could use Vite's loadConfigFromFile() instead, but I was not sure how to align its arguments and Nuxt things. 🤔

https://github.com/vitejs/vite/blob/8fe69524d25d45290179175ba9b9956cbce87a91/packages/vite/src/node/config.ts#L896

Would anyone give me a help?

[NozomuIkuta]

Here, we could use Vite's loadConfigFromFile() instead

I mean, it will return null if there is no config file found.

[danielroe]

I think your approach is more minimal, and the warning is a 'nice-to-have' extra so it is fine if we don't detect an edge case.

You could consider using resolvePath from mlly or Nuxt Kit to resolve the config file which might simplify the implementation here.

[NozomuIkuta]

Should I apply this kind of logic to webpack package too?

[Hebilicious]

It would be nice if we had a Build section in the docs (similar to the deployment section), that goes more into the details of how the build process works.
And within it, there should be a vite section that explains that you can't have a vite.config file and that to modify the vite config, you have some access through nuxt.config.ts, but you need to use the hooks to have full control

[danielroe]

Should I apply this kind of logic to webpack package too?

Absolutely, if webpack has the same behaviour. Though I think we could do it in a separate PR.