Vitest rendering an empty div when RouterProvider is used

I have found that when unit testing with Vitest, if I pass a RouterProvider to the render function, the result is always a empty div, i.e:

<body>
  <div />
</body>

<body>
  <div />
</body>

<body>
  <div />
</body>

<body>
  <div />
</body>

I've tried to follow a couple of examples of wrappers that have been posted here and on GitHub, but they all have the same result.

I've created a minimal reproduction here:
https://stackblitz.com/edit/tanstack-router-1wnwna?file=src%2Fmain.test.tsx&view=editor

Just run

npm run test

npm run test

npm run test

npm run test to see what I mean.

Any advice is greatly appreciated.

Run official live example code for Router Basic, created by Tanstack on StackBlitz