gnu: Add Guix-Modules.

* gnu/packages/package-management.scm (guix-modules): New variable.

gnu/packages/package-management.scm

@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2013-2022 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2015, 2017, 2020, 2021, 2022 Ricardo Wurmus <rekado@elephly.net>
 ;;; Copyright © 2017 Muriithi Frederick Muriuki <fredmanglis@gmail.com>
 ;;; Copyright © 2017, 2018 Oleg Pykhalov <go.wigust@gmail.com>
@@ -111,6 +111,7 @@
   #:use-module (gnu packages version-control)
   #:use-module (guix build-system glib-or-gtk)
   #:use-module (guix build-system gnu)
+  #:use-module (guix build-system guile)
   #:use-module (guix build-system meson)
   #:use-module (guix build-system python)
   #:use-module (guix build-system trivial)
@@ -660,6 +661,50 @@ out) and returning a package that uses that as its 'source'."
 the Icon Theme Specification.  They can be used by applications querying the
 GTK icon cache for instance.")))
 
+(define-public guix-modules
+  (package
+    (name "guix-modules")
+    (version "0.1.0")
+    (home-page "https://gitlab.inria.fr/guix-hpc/guix-modules")
+    (source (origin
+              (method git-fetch)
+              (uri (git-reference (url home-page)
+                                  (commit (string-append "v" version))))
+              (file-name (string-append "guix-modules-" version "-checkout"))
+              (sha256
+               (base32
+                "1ckvrrmkgzz93i35sj1372wxs7ln4gzszpri1pcdf473z0p7nh7w"))))
+    (build-system guile-build-system)
+    (arguments
+     '(#:phases (modify-phases %standard-phases
+                  (add-after 'install 'move-to-extension-directory
+                    (lambda* (#:key outputs #:allow-other-keys)
+                      (let* ((out (assoc-ref outputs "out"))
+                             (target (string-append
+                                      out
+                                      "/share/guix/extensions/module.scm")))
+                        (mkdir-p (dirname target))
+                        (rename-file (car (find-files out "module.scm"))
+                                     target)))))))
+    (native-inputs (list (lookup-package-input guix "guile") guix))
+    (synopsis "Generate environment modules from Guix packages")
+    (description
+     "Guix-Modules is an extension of Guix that provides a new @command{guix
+module} command.  The @command{guix module create} sub-command creates
+@dfn{environment modules}, allowing you to manipulate software environments
+with the @command{module} command commonly found on @acronym{HPC,
+high-performance computing} clusters.
+
+To use this extension, set the @env{GUIX_EXTENSIONS_PATH} environment
+variable, along these lines:
+
+@example
+export GUIX_EXTENSIONS_PATH=\"$HOME/.guix-profile/share/guix/extensions\"
+@end example
+
+Replace @code{$HOME/.guix-profile} with the appropriate profile.")
+    (license license:gpl3+)))
+
 
 ;;;
 ;;; Other tools.