[lib mode] name confliction when using dynamic imports

[pd4d10]

Describe the bug

If multiple formats are specified in the lib mode, the dynamic imports chunk names would be the same and be unexpectedly overrode.

For more information, see the reproduction link below: Both es and cjs builds emit a file named dist/utils.js.

Reproduction

https://stackblitz.com/edit/vitejs-vite-egee8a

System Info

Not related

Used Package Manager

npm

Logs

No response

Validations

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• The provided reproduction is a minimal reproducible example of the bug.