bug#57467: 'guix shell' does not honor default behavior when given a specific command to run

[Ludovic Courtès]

Maxime Devos <maximedevos@telenet.be> skribis:

> On 05-09-2022 15:06, Ludovic Courtès wrote:
>> The main difficulty here is that, should we eventually decide to change
>> behaviors, we’ll have to devise a migration timeline etc.  (As an
>> example, we chose to keep ‘guix environment’ until at least May 2023;
>> all this must take time if we want to avoid breaking user workflows.)
>>
>> Thoughts?
>
> "guix shell" is for making packages available in the
> environment. Currently, "guix shell -- foobar" does not make any
> packages available -- it's effectively a no-op except for setting
> GUIX_ENVIRONMENT.

True, though you could always have scripts that read:

  guix shell $packages -- whatever

and that will suddenly behave differently if $packages expands to an
empty string.  Tricky!

Ludo’.