bug#34679: --load-path does not work with guix environment

[Hartmut Goebel]

According to the manual:

|--load-path=directory|

    Add directory *to the front* of the package module search path.

This does not work for guix environment (guix 0.16.0-3.6ddc63e):

Prepare to reproduce

$ git clone https://gnunet.org/git/gnunet.git
$ cd gnunet


guix package honors --load-path:

$ guix package --load-path=$PWD/contrib/guix -A gnunet

[...]
gnunet  v0.11.0pre66-1108-g8bb29d2fb    out    
.../contrib/guix/gnu/packages/gnunet.scm:274:2
[...]


guix environment still installs gnunet 0.10.1 (which is defined in guix
0.16):

$ guix environment --load-path=$PWD/contrib/guix --ad-hoc gnunet
[guix]$ realpath $(which gnunet-arm)
/gnu/store/...-gnunet-0.10.1/bin/gnunet-arm


Using GUIX_PACKAGE_PATH the correct version of gnunet is installed into
the environment:

$ export GUIX_PACKAGE_PATH=$PWD/contrib/guix
$ guix environment --ad-hoc gnunet
[guix]$ realpath $(which gnunet-arm)
/gnu/store/...-gnunet-v0.11.0pre66-1108-g8bb29d2fb/bin/gnunet-arm


-- 
Regards
Hartmut Goebel

| Hartmut Goebel          | address@hidden               |
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