bug#51425: file-system: validate flags

[Maxim Cournoyer]

Hello,

Jonathan Brielmaier <jonathan.brielmaier@web.de> writes:

> Imagine the following file system definition in your config.scm:
>
> ```
> (file-system
>   (device (uuid "UUID-123"))
>   (flags '((create-mount-point? #t)))
>   (mount-point "/mnt")
>   (type "ext4")))
> ```
>
> When you reconfigure there will be no complain, but when you reboot your
> system wont boot. The parameter to flags is nonsense, it should be
> something like: `read-only`. So mounting of the file system will fail...
>
> It would be nice if we can have some flag validation during reconfigure.
>
> ~Jonathan

I agree that it'd be nice; I had gotten close to implementing such a
thing in the past, but it was discussed and abandoned because each file
system may have their own flags, add new flags with new releases, etc,
which means it'd be difficult to keep the list accurate.

That's if my memory serves me right :-).

Thanks,

Maxim