`npm run check` fails on newly bootstrapped SvelteKit project with vitest

[mjswensen]

Describe the bug

There is a type mismatch between the Vite plugins returned by sveltekit() (from @sveltejs/kit/vite) and what's expected by vitest/config.

Reproduction

1. (Optional: get into a Docker container with Node.js installed: docker run --rm -it mcr.microsoft.com/devcontainers/javascript-node:20 bash)
2. Run npx sv create my-app
   • Choose "SvelteKit minimal" for the template.
   • Choose "Yes, using Typescript syntax" for TS support.
   • Select "vitest" for the project add-on.
   • Choose "npm" for the package manager.
3. Run npm run check

Logs

The error is `Type 'Plugin<any>' is not assignable to type 'false | Plugin<any> | PluginOption[] | null | undefined'.`.

System Info

System:
    OS: Linux 6.8 Debian GNU/Linux 12 (bookworm) 12 (bookworm)
    CPU: (4) arm64 unknown
    Memory: 12.91 GB / 15.58 GB
    Container: Yes
    Shell: 5.2.15 - /bin/bash
  Binaries:
    Node: 20.14.0 - /usr/local/bin/node
    Yarn: 1.22.22 - /usr/local/bin/yarn
    npm: 10.7.0 - /usr/local/bin/npm
    pnpm: 9.1.4 - /usr/local/share/npm-global/bin/pnpm
  npmPackages:
    svelte: ^5.0.0 => 5.5.3

Severity

annoyance

[frederikhors]

@mjswensen I opened sveltejs/kit#13102 for this. vitest is the issue. Downgrade to 2.1.6 for now fixes it.

[mjswensen]

Thank you @frederikhors ! 🙏