elisp: Add support for "--format" option of "guix pack" command

Follow the changes introduced by
<http://git.savannah.gnu.org/cgit/guix.git/commit/?id=b1edfbc37f2f008188d91f594b046c5986485e47>.

* scheme/emacs-guix/pack.scm (pack-format-names): New procedure.
* scheme/emacs-guix.scm: Autoload it.
* elisp/guix-read.el (guix-pack-format-names)
(guix-read-pack-format-name): New procedures.
* elisp/guix-command.el (guix-command-improve-pack-argument): Complete
"--format" option.
* elisp/guix-pcomplete.el (guix-pcomplete-complete-option-arg): Likewise.

5 files changed, 26 insertions, 2 deletions

diff --git a/elisp/guix-command.el b/elisp/guix-command.el
index ace0920..4664ac1 100644
--- a/elisp/guix-command.el
+++ b/elisp/guix-command.el
@@ -247,6 +247,7 @@ to be modified."
 (guix-command-define-argument-improver
     guix-command-improve-pack-argument
   '(("--compression" :fun guix-read-compressor-name)
+    ("--format" :fun guix-read-pack-format-name)
     ;; "--symlink" is not completed as it should be "FILE-NAME=TARGET".
     ;; ("--symlink" :fun guix-read-file-name)
     ))
diff --git a/elisp/guix-pcomplete.el b/elisp/guix-pcomplete.el
index fcc974d..0babdb1 100644
--- a/elisp/guix-pcomplete.el
+++ b/elisp/guix-pcomplete.el
@@ -246,6 +246,8 @@ INPUT is the current partially completed string."
       (cond
        ((option? "-C" "--compression")
         (complete* (guix-compressor-names)))
+       ((option? "-f" "--format")
+        (complete* (guix-pack-format-names)))
        ;; Although the argument should be "FILE-NAME=TARGET", it is
        ;; still better to complete the FILE-NAME than to complete
        ;; nothing.
diff --git a/elisp/guix-read.el b/elisp/guix-read.el
index 4dde74e..b455992 100644
--- a/elisp/guix-read.el
+++ b/elisp/guix-read.el
@@ -51,6 +51,10 @@
   "Return a list of names of available compressors."
   (guix-eval-read "(compressor-names)"))
 
+(guix-memoized-defun guix-pack-format-names ()
+  "Return a list of names of available pack formats."
+  (guix-eval-read "(pack-format-names)"))
+
 (guix-memoized-defun guix-package-names ()
   "Return a list of names of available packages."
   (sort (guix-eval-read "(package-names)")
@@ -137,6 +141,11 @@
  :single-prompt "Compressor: ")
 
 (guix-define-readers
+ :completions-getter guix-pack-format-names
+ :single-reader guix-read-pack-format-name
+ :single-prompt "Pack format: ")
+
+(guix-define-readers
  :completions-getter guix-package-names
  :require-match nil
  :single-reader guix-read-package-name
diff --git a/scheme/emacs-guix.scm b/scheme/emacs-guix.scm
index d337807..f054481 100644
--- a/scheme/emacs-guix.scm
+++ b/scheme/emacs-guix.scm
@@ -56,7 +56,8 @@
                                  make-package-graph)
   #:autoload (emacs-guix lint) (lint-checker-names
                                 lint-package)
-  #:autoload (emacs-guix pack) (compressor-names)
+  #:autoload (emacs-guix pack) (compressor-names
+                                pack-format-names)
   #:autoload (emacs-guix refresh) (refresh-updater-names))
 
 ;;; emacs-guix.scm ends here
diff --git a/scheme/emacs-guix/pack.scm b/scheme/emacs-guix/pack.scm
index 03c9914..cdc2dd8 100644
--- a/scheme/emacs-guix/pack.scm
+++ b/scheme/emacs-guix/pack.scm
@@ -20,12 +20,23 @@
 ;;; Code:
 
 (define-module (emacs-guix pack)
+  #:use-module (ice-9 match)
+  #:use-module (srfi srfi-1)
   #:use-module (guix scripts pack)
-  #:export (compressor-names))
+  #:export (compressor-names
+            pack-format-names))
 
 (define (compressor-names)
   "Return a list of names of available pack compressors."
   (map (@@ (guix scripts pack) compressor-name)
        (@@ (guix scripts pack) %compressors)))
 
+(define (pack-format-names)
+  "Return a list of names of available pack formats."
+  (filter-map (match-lambda
+                ((name . _proc)
+                 (symbol->string name))
+                (_ #f))
+              (@@ (guix scripts pack) %formats)))
+
 ;;; pack.scm ends here