bug#53397: --dry-run not effective on 'guix pull'

[Maxim Cournoyer]

Hi again,

Maxim Cournoyer <maxim.cournoyer@gmail.com> writes:

> Hello,
>
> The 'guix pull' command a --dry-run option, per "guix pull --help", but
> it doesn't work:
>
> $ guix pull --commit=1995920f687020720d22bf8656fdde5ea1908747 --dry-run
> Updating channel 'guix' from Git repository at 
> 'https://git.savannah.gnu.org/git/guix.git'...
> Updating channel 'sfl-packages' from Git repository at 
> 'https://gitlab.com/Apteryks/sfl-guix-channel'...
> Building from these channels:
>   sfl-packageshttps://gitlab.com/Apteryks/sfl-guix-channel      6385881
>   guix      https://git.savannah.gnu.org/git/guix.git   1995920
> substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
> substitute: updating substitutes from 'https://bordeaux.guix.gnu.org'... 
> 100.0%
> building 
> /gnu/store/z3s04zx6cncpfffqhg1g8fkzyiiran54-compute-guix-derivation.drv...
> Computing Guix derivation for 'x86_64-linux'... |^C

It seems I should have been a bit more patient.  The full command read
as:

--8<---------------cut here---------------start------------->8---
$ guix pull --commit=1995920f687020720d22bf8656fdde5ea1908747 --dry-run
Updating channel 'guix' from Git repository at 
'https://git.savannah.gnu.org/git/guix.git'...
Updating channel 'sfl-packages' from Git repository at 
'https://gitlab.com/Apteryks/sfl-guix-channel'...
Building from these channels:
  sfl-packageshttps://gitlab.com/Apteryks/sfl-guix-channel      6385881
  guix      https://git.savannah.gnu.org/git/guix.git   1995920
Computing Guix derivation for 'x86_64-linux'... -
                                                                                
                         \
substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
substitute: updating substitutes from 'https://bordeaux.guix.gnu.org'... 100.0%
The following derivations would be built:
   /gnu/store/y89p6mxyng59ql27bzkz6mpl29f4d42a-profile.drv
   /gnu/store/0zfzgpdir6xhnwhnshlam85mcld7ynnb-sfl-packages.drv
   /gnu/store/25rvqdz96f16hqnhlli6aajhcap70k40-guix-1995920f6.drv
   /gnu/store/ijail6rcqvl3nl115qwka2whn8l5mi24-guix-daemon.drv
   /gnu/store/wnr4j0hcjcfzcxc8jd8k44av5982nir2-guix-command.drv
   /gnu/store/dvlcml6mk0iy7zfjwyc3md0ahw6gghvd-guix-module-union.drv
   /gnu/store/yvisngmzfq2hprmhbwi1671y10zswmvh-guix-1995920f6-modules.drv
   /gnu/store/p5b0y71lhmlsga7f643acgcw50klr34q-guix-config-modules.drv
   /gnu/store/qvxcm42f8bdzj62l34jhyd53kci695mb-guix-config-source.drv
   /gnu/store/wjimxiq7npfrdhyzw61q50x6392pfc7c-config.scm.drv
   /gnu/store/slzxkifcrwx6vn1q0dkjgfsfbkij3hpy-guix-config.drv
   /gnu/store/pf123iw6bmf9c19lim91p4m16r0b9gl8-guix-core-modules.drv
   /gnu/store/zsrz3yk8r8261svnk80sd4407vn70wpq-guix-packages-modules.drv
   /gnu/store/ach8s5bsb30n04v584fnhfiq83nrkiy6-inferior-script.scm.drv
   /gnu/store/2ykcwnrmypv2sywjlqi548sjs3k3n47v-profile.drv
   /gnu/store/31p0x6jps8l8p7z5kkkncj8mpca9pyz6-inferior-script.scm.drv

2.2 MB would be downloaded
--8<---------------cut here---------------end--------------->8---

So the derivations had to be computed before the build plan could be
printed (which makes sense in retrospect).

Apologies, closing!

Maxim