bug#50978: "guix home describe" backtraces if "guix home" hasn't been used

["Ludovic Courtès" <ludo@gnu.org>]

Hi,

Xinglu Chen <public@yoctocell.xyz> skribis:

> On Sat, Oct 02 2021, Maxime Devos wrote:
>
>> Hi,
>>
>> When running "guix home describe" before "guix home import"
>> and before "guix build":
>>
>> $ guix home  describe
>> Backtrace:
>>            7 (primitive-load "/home/[...]/.config/guix/current/b…")
>> In guix/ui.scm:
>>    2185:7  6 (run-guix . _)
>>   2148:10  5 (run-guix-command _ . _)
>> In ice-9/boot-9.scm:
>>   1752:10  4 (with-exception-handler _ _ #:unwind? _ # _)
>> In guix/status.scm:
>>     820:3  3 (_)
>>     800:4  2 (call-with-status-report _ _)
>> In guix/scripts/home.scm:
>>     263:8  1 (_)
>> In ice-9/boot-9.scm:
>>   1685:16  0 (raise-exception _ #:continuable? _)
>>
>> ice-9/boot-9.scm:1685:16: In procedure raise-exception:
>> no home environment generation, nothing to describe~%
>>
>> I don't think a backtrace is needed here.
>
> This seems to be the case for ‘guix system describe’ too
>
> $ guix system describe
> Backtrace:
>            7 (primitive-load "/home/yoctocell/.config/guix/current/bin/guix")
> In guix/ui.scm:
>    2185:7  6 (run-guix . _)
>   2148:10  5 (run-guix-command _ . _)
> In ice-9/boot-9.scm:
>   1752:10  4 (with-exception-handler _ _ #:unwind? _ #:unwind-for-type _)
> In guix/status.scm:
>     820:3  3 (_)
>     800:4  2 (call-with-status-report _ _)
> In guix/scripts/system.scm:
>    1310:8  1 (_)
> In ice-9/boot-9.scm:
>   1685:16  0 (raise-exception _ #:continuable? _)
>
> ice-9/boot-9.scm:1685:16: In procedure raise-exception:
> no system generation, nothing to describe~%

Fixed in a9268216e4f38189d7948cf2ecb51ad2eac7e586, thanks!

Ludo'.