"Not found: /" error in dev mode when you have no root route

[johnnysprinkles]

Describe the bug

This is pretty minor, but if you're using adapter-static and building a subtree that you'll be shoehorning into some other legacy app, you might not need the root route /. If you don't have one, you get this error every time you restart the dev server and you have a browser window open:

jpsimons@Johns-iMac sveltekit_no_root_path % npm run dev

> [email protected] dev
> vite dev


  VITE v3.1.7  ready in 242 ms

  ➜  Local:   http://localhost:5173/
  ➜  Network: use --host to expose
Not found: /
Error: Not found: /
    at resolve (file:///Users/jpsimons/dev/sveltekit_no_root_path/node_modules/@sveltejs/kit/src/runtime/server/index.js:259:13)
    at resolve (file:///Users/jpsimons/dev/sveltekit_no_root_path/node_modules/@sveltejs/kit/src/runtime/server/index.js:290:5)
    at Object.handle (file:///Users/jpsimons/dev/sveltekit_no_root_path/node_modules/@sveltejs/kit/src/exports/vite/dev/index.js:336:66)
    at respond (file:///Users/jpsimons/dev/sveltekit_no_root_path/node_modules/@sveltejs/kit/src/runtime/server/index.js:287:40)
    at async file:///Users/jpsimons/dev/sveltekit_no_root_path/node_modules/@sveltejs/kit/src/exports/vite/dev/index.js:406:22
^C

Not sure why anything would be trying to load /, my browser is sitting on the route that exists, i.e. http://localhost:5173/blah

Reproduction

Repro example at https://github.com/johnnysprinkles/sveltekit_no_root_path/commits/main It's just the stock skeleton app with the only route moved down a folder.

Logs

No response

System Info

System:
    OS: macOS 12.2.1
    CPU: (8) arm64 Apple M1
    Memory: 78.38 MB / 8.00 GB
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 18.10.0 - ~/.nvm/versions/node/v18.10.0/bin/node
    npm: 8.19.2 - ~/.nvm/versions/node/v18.10.0/bin/npm
  Browsers:
    Firefox: 105.0.1
    Safari: 15.3
  npmPackages:
    @sveltejs/adapter-auto: next => 1.0.0-next.81
    @sveltejs/kit: next => 1.0.0-next.512
    svelte: ^3.44.0 => 3.51.0
    vite: ^3.1.0 => 3.1.7

Severity

annoyance

Additional Information

No response

[gtm-nayan]

This seems to be because of the ping requests sent by vite when you close the server after loading a page.

Although, I don't see anything special in those requests for us to identify them currently.

cc @bluwy, would a header like X-Vite-Ping: true be possible to add upstream?