bug#41764: `make authenticate` fails to find the keyring branch

["Ludovic Courtès" <ludo@gnu.org>]

Hi!

Miguel Ángel Arruga Vivas <rosen644835@gmail.com> skribis:

> From 479ac6846cb228b67b778965f0f5299ea3172424 Mon Sep 17 00:00:00 2001
> From: =?UTF-8?q?Miguel=20=C3=81ngel=20Arruga=20Vivas?=
>  <rosen644835@gmail.com>
> Date: Sat, 24 Oct 2020 14:35:09 +0200
> Subject: [PATCH] build: Add GUIX_GIT_KEYRING variable for make authenticate.
>
> * Makefile.am (GUIX_GIT_KEYRING): New variable.
> (authenticate): Use GUIX_GIT_KEYRING to select the keyring branch
> reference.
> * doc/contributing.texi (Building from Git): Add an example about the
> use of GUIX_GIT_KEYRING.
> ---
>  Makefile.am           |  2 ++
>  doc/contributing.texi | 10 ++++++++++
>  2 files changed, 12 insertions(+)
>
> diff --git a/Makefile.am b/Makefile.am
> index c509562567..e6cef9ec1a 100644
> --- a/Makefile.am
> +++ b/Makefile.am
> @@ -666,9 +666,11 @@ channel_intro_commit = 9edb3f66fd807b096b48283debdcddccfea34bad
>  channel_intro_signer = BBB0 2DDF 2CEA F6A8 0D1D  E643 A2A0 6DF2 A33A 54FA
>  
>  # Authenticate the current Git checkout by checking signatures on every commit.
> +GUIX_GIT_KEYRING = origin/keyring

You need “?=” or users won’t be able to override it.

>  authenticate:
>  	$(AM_V_at)echo "Authenticating Git checkout..." ;	\
>  	guix git authenticate					\
> +	    --keyring=$(GUIX_GIT_KEYRING)			\
>  	    --cache-key=channels/guix --stats			\
>  	    "$(channel_intro_commit)" "$(channel_intro_signer)"
>  
> diff --git a/doc/contributing.texi b/doc/contributing.texi
> index 26a4627464..9312faa849 100644
> --- a/doc/contributing.texi
> +++ b/doc/contributing.texi
> @@ -140,6 +140,16 @@ make authenticate
>  
>  The first run takes a couple of minutes, but subsequent runs are faster.
>  
> +Or, when your configuration for your local git repository doesn't match
> +the default one, you can provide the reference for the @code{keyring}
> +branch through the variable @code{GUIX_GIT_KEYRING}.  The following
> +example assumes that you have a git remote called @samp{myremote}
> +pointing to the official repository:
> +
> +@example
> +make authenticate GUIX_GIT_KEYRING=myremote/keyring
> +@end example

s/git/Git/ in the paragraph, but otherwise LGTM!  ‘origin/keyring’ is
certainly a better default than ‘keyring’.

Thanks,
Ludo’.