`plugins` applies to worker only for dev and requires `worker.plugins` for build

[zhmushan]

Describe the bug

Only by adding this plugin to rollup as well will it pass compilation.

import plugin from './plugin.js';

export default {
  plugins: [plugin()],
  build: {
    rollupOptions: {
      // plugins: [plugin()],
    },
  },
};

More details can be found in the reproduction. trust me, it is a minimal and will not waste too much of your time.

Reproduction

https://stackblitz.com/edit/vitejs-vite-mojc3s?file=vite.config.js

System Info

n/a

Used Package Manager

pnpm

Logs

No response

Validations

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• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
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• The provided reproduction is a minimal reproducible example of the bug.

[sapphi-red]

Changing the config like below will fix this.

import plugin from './plugin.js';

export default {
  plugins: [plugin()],
  worker: {
    plugins: [plugin()]
  }
};

I'm not sure why worker.plugins exists separately.

[poyoho]

@sapphi-red #6243 (comment) Related discussion here

Maybe we should expand on this in the documentation?

[sapphi-red]

@poyoho Thanks I see.
Yes, I think this is difficult to notice and it would be nice to have a document about this.

[zhmushan]

For consistency, we should also keep the root-level plugin from taking effect on worker during the dev phase. Or print a warning message.