[bug#61910] [PATCH] git-download: Download a bare Git repository from SWH.

[Ludovic Courtès]

Fixes a bug whereby CR/LF convention would not be applied on Git
repositories retrieved from SWH:

  https://sympa.inria.fr/sympa/arc/swh-devel/2023-03/msg00000.html

Reported by Simon Tournier <simon.tournier@inserm.fr>.
Suggested by Valentin Lorentz <valentin.lorentz@inria.fr>.

* guix/git-download.scm (git-fetch)[build]: Pass #:archive-type to
'swh-download' and invoke "git clone" on the result.
---
 guix/git-download.scm | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

Hi there!

I just saw the discussion between Simon and Valentin (Cc’d) and
realized this could easily be fixed on our side because (guix swh)
is already equipped to fetch bare Git repositories.

To test it, comment out the ‘git-fetch’ and ‘download-nar’ calls in
(guix git-download) and run, say:

  ./pre-inst-env guix build -S guile-bash --check

I don’t know of a repository that has this CRLF problem though, so
we should check that it actually works as advertised on such a repo.

Thanks,
Ludo’.

diff --git a/guix/git-download.scm b/guix/git-download.scm
index a1566bed4d..9f57b4170d 100644
--- a/guix/git-download.scm
+++ b/guix/git-download.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Ludovic Courtès 
<ludo@gnu.org>
+;;; Copyright © 2014-2021, 2023 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2017 Mathieu Lirzin <mthl@gnu.org>
 ;;; Copyright © 2017 Christopher Baines <mail@cbaines.net>
 ;;; Copyright © 2020 Jakub Kądziołka <kuba@kadziolka.net>
@@ -162,8 +162,17 @@ (define recursive?
                      (parameterize ((%verify-swh-certificate? #f))
                        (format (current-error-port)
                                "Trying to download from Software 
Heritage...~%")
+
+                       ;; Fetch the source as a bare Git repository (rather
+                       ;; than 'flat') so Git can post-process it in the usual
+                       ;; way, for instance to perform CR/LF conversion.
                        (swh-download (getenv "git url") (getenv "git commit")
-                                     #$output))))))))
+                                     "git-repo"
+                                     #:archive-type 'git-bare)
+                       (invoke #+(file-append git "/bin/git")
+                               "clone" "git-repo" #$output)
+                       (delete-file-recursively
+                        (string-append #$output "/.git")))))))))
 
   (mlet %store-monad ((guile (package->derivation guile system)))
     (gexp->derivation (or name "git-checkout") build

base-commit: ff5fbcc19bce6e94ead0cc79b27ae8ed0307463d
-- 
2.39.1