`Cannot redefine property` error during module spread as props

[x0k]

Describe the bug

The following code <Component {...someModule} {foo} /> results in a Cannot redefine property: foo error if the module exports a variable named foo.

Reproduction

SvelteLab

The error does not occur in the Svelte Playground, so it’s likely related to Vite.

Logs

System Info

System:
    OS: Linux 6.12 cpe:/o:nixos:nixos:25.05 25.05 (Warbler)
    CPU: (12) x64 Intel(R) Core(TM) i5-10400F CPU @ 2.90GHz
    Memory: 2.34 GB / 15.56 GB
    Container: Yes
    Shell: 5.2.37 - /run/current-system/sw/bin/bash
  Binaries:
    Node: 24.7.0 - /nix/store/ffx0ixqnd6arwnjqmjv844krhay4iycj-nodejs-24.7.0/bin/node
    npm: 11.5.1 - /nix/store/ffx0ixqnd6arwnjqmjv844krhay4iycj-nodejs-24.7.0/bin/npm
    pnpm: 10.15.1 - /nix/store/dmnyvw4gf3i8b65s3k7q4ws3257m6zrs-pnpm-10.15.1/bin/pnpm
  Browsers:
    Brave Browser: 141.1.83.118
  npmPackages:
    svelte: ^5.30.0 => 5.43.14

Severity

annoyance

[webJose]

Seems to be a Sveltekit-only problem. In the REPL this doesn't happen.

REPL

Ah, ok. Yes, I just saw the error stack trace. Comes from the server side of things.