Subject: [bug#54304] [PATCH] Don't fix git executable location during Elixir build

From: Cees de Groot <[email-masked]>
Date: Tue, 08 Mar 2022 20:52:00 +0000

The removed code below affected two locations where Elixir uses Git:

* At build-time, Git is used to see if the build is inside a Git repo and if so, git info
  is added to the build information that Elixir returns with `System.build_info()`. The code
  uses PATH + `git` so the Git version from the inputs is used which is just fine.
* At run-time, Git is used by Mix if, and only if, there are any Git-based dependencies. This
  is not the normal case, and in that sense Git is an optional dependency of Elixir - most
  projects will work just fine without Git being present. Here, too, PATH + `git` is used
  so if there is a need on a user's system to use Git-based dependencies, the user can just
  add the package to the profile and things will just work.

I feel that leaving this alone is cleaner than trying to fix the dependency (if we want to
keep it, it needs to be in propagated-inputs in order to keep Git around; I stumbled upon
this building a project with Git dependencies after doing a `guix gc`. However, given that
using Git dependencies is the exception and I think that minimizing dependencies is nicer
I opted to just remove the substition completely).

---
 gnu/packages/elixir.scm | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/gnu/packages/elixir.scm b/gnu/packages/elixir.scm
index 55e17f2901..f509c59ee3 100644
--- a/gnu/packages/elixir.scm
+++ b/gnu/packages/elixir.scm
@@ -60,11 +60,6 @@ (define-public elixir
               (for-each make-file-writable (find-files "."))))
           (add-after 'make-git-checkout-writable 'replace-paths
             (lambda* (#:key inputs #:allow-other-keys)
-              (substitute* '("lib/elixir/lib/system.ex"
-                             "lib/mix/lib/mix/scm/git.ex")
-                (("(cmd\\(['\"])git" _ prefix)
-                 (string-append prefix
-                                (search-input-file inputs "/bin/git"))))
               (substitute* '("lib/mix/lib/mix/release.ex"
                              "lib/mix/lib/mix/tasks/release.init.ex")
                 (("#!/bin/sh")
--
2.34.0