bug#52347: Shell: error when -m manifest is removed

[Ludovic Courtès]

Hi Cayetano,

Cayetano Santos <cayetano.santos@inventati.org> skribis:

>  Following command works
>
>    guix shell --container -m manifest.scm -- python3
>
>  But
>
>    guix shell --container -- python3
>
> gives an error. However,
>
>    guix shell --container
>
> followed by
>
>    python3
>
> works.
>
>  So, by just removing the ’-m manifest.scm’ flag, I get an error.

As Liliana noted, this is the intended behavior: auto-loading of
‘manifest.scm’ happens only for interactive use.  This is to keep
non-interactive use context-independent and thereby avoid bad surprises.

Note that when ‘manifest.scm’ is auto-loaded, a message is printed; when
it’s not considered, no message is printed.  Likewise, when creating an
empty environment, a warning is printed (twice even :-)).

Any suggestions on things we might improve to avoid confusion?

Thanks,
Ludo’.