When using Qt.resolvedUrl to generate path in U1db.Database, the document contents are invalid

See the attached example, I'm trying to set the fullpath of the dabase using Qt.resolvedUrl("settings.db").split("://")[1] (as a workaround of bug #1426180), but the given example (when saved in /tmp), when ran returns:

  Settings saved in /tmp/settings.db; settings contents is undefined

For some reason the document contents is undefined.
The example, correctly generates the "settings.db", but it has no default data in it.

If I replace, the the generated path with the full path of the file (so in my case 'path: "/tmp/settings.db"'), then it works.
This seems pretty weird.

Once generated, I can go back to the version with Qt.resolvedUrl and it seems to work again.