bug#66705: ‘guix shell -CW’ provides a Guix command without extra channels

["Ludovic Courtès" <ludo@gnu.org>]

Ludovic Courtès <ludovic.courtes@inria.fr> skribis:

> This is due to the fact that ‘-W’ (‘--nesting’) is implemented by adding
> the outer ‘guix’ to the container’s profile, without also adding its
> companion profile entries (those that provide channels).

Actually, the original profile, which contains ‘guix’ and its channels,
*is* available in the environment:

--8<---------------cut here---------------start------------->8---
$ guix time-machine -C <(echo '(cons (channel (name (quote guix-hpc)) (url "https://gitlab.inria.fr/guix-hpc/guix-hpc.git")) %default-channels)') -- shell -CW coreutils 
[env]$ readlink -f $(type -P guix)
/gnu/store/42731vcvzl6nrwa584mziwhpvp4xs72r-guix-command
[env]$ type -P guix
/gnu/store/ca142m4lm0grxmsjqrcqpfl5qb5i1rka-profile/bin/guix
[env]$ readlink $(type -P guix)
/gnu/store/j5g09kjd7pv1b6919vbsnjs160xfw9md-profile/bin/guix
[env]$ /gnu/store/j5g09kjd7pv1b6919vbsnjs160xfw9md-profile/bin/guix describe
  guix cbd20d6
    repository URL: https://git.savannah.gnu.org/git/guix.git
    branch: master
    commit: ]8;;https://git.savannah.gnu.org/cgit/guix.git/commit/?id=cbd20d627497053871db863970c07d93c7081786\cbd20d627497053871db863970c07d93c7081786]8;;\
  guix-hpc 887d76a
    repository URL: https://gitlab.inria.fr/guix-hpc/guix-hpc.git
    branch: master
    commit: ]8;;https://gitlab.inria.fr/guix-hpc/guix-hpc/commit/887d76a8e1d0f35d615c613b28b9b871f39a997e\887d76a8e1d0f35d615c613b28b9b871f39a997e]8;;\
--8<---------------cut here---------------end--------------->8---

The problem is the extra profile layer that confuses
‘current-channel-entries’ in (guix describe).

Ludo’.