Subject: [PATCH v4] pull: allow filtering which channels to pull from the CLI

From: Sergio Pastor Pérez <[email-masked]>
Date: Sun, 25 May 2025 12:55:02 +0200

* guix/scripts/pull.scm (guix-pull): treat non-prefix CLI arguments as a list
of channels to pull.

Change-Id: I5d08c4b1cc84ab58a9c4e7600eb86468f92d10f0
---
 doc/guix.texi         | 10 ++++++--
 guix/scripts/pull.scm | 53 ++++++++++++++++++++++++++++++++++++-------
 2 files changed, 53 insertions(+), 10 deletions(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index e4e2b853f1..26f16cfa7a 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -4656,8 +4656,14 @@ Invoking guix pull
 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
 @end example
 
-The @command{guix pull} command is usually invoked with no arguments,
-but it supports the following options:
+The general syntax is:
+
+@example
+guix pull [@var{options}] [@var{CHANNELS}@dots{}]
+@end example
+
+The optional @var{channels} argument filters the list of pulled channels
+to those whose names match the given list.
 
 @table @code
 @item --url=@var{url}
diff --git a/guix/scripts/pull.scm b/guix/scripts/pull.scm
index 76aed0b5cc..fc6809d68c 100644
--- a/guix/scripts/pull.scm
+++ b/guix/scripts/pull.scm
@@ -81,8 +81,12 @@ (define %default-options
     (validate-pull . ,ensure-forward-channel-update)))
 
 (define (show-help)
-  (display (G_ "Usage: guix pull [OPTION]...
-Download and deploy the latest version of Guix.\n"))
+  (display (G_ "Usage: guix pull [OPTION]... [CHANNELS...]
+Download and deploy the latest version of Guix.
+
+If CHANNELS are specified, pull only from channels with those names (e.g.:
+'guix pull rde nonguix' pulls only from the 'guix', 'rde', and 'nonguix'
+channels as defined in your channel configuration).\n"))
   (display (G_ "
   -C, --channels=FILE    deploy the channels defined in FILE"))
   (display (G_ "
@@ -839,21 +843,52 @@ (define (validate-cache-directory-ownership)
 (define-command (guix-pull . args)
   (synopsis "pull the latest revision of Guix")
 
-  (define (no-arguments arg _)
-    (leave (G_ "~A: extraneous argument~%") arg))
+  (define (unpin-channels channels current-channels names)
+    "Unpin CHANNELS whose name symbol is present in NAMES list.
+If NAMES is an empty list, don't filter anything.  Warn when a name is not
+available in the channels list."
+    (if (null? names)
+        channels
+        (let ((available-names (map channel-name
+                                    channels))
+              (selected-channels (filter (lambda (ch)
+                                           (member (channel-name ch)
+                                                   names))
+                                         channels)))
+          (for-each (lambda (name)
+                      (unless (member name available-names)
+                        (warning (G_ "Channel '~a' not present in channel list~%")
+                                 name)))
+                    names)
+
+          (map (lambda (cur-ch)
+                 (let ((selected-channel (find (lambda (ch)
+                                                 (eq? (channel-name ch)
+                                                      (channel-name cur-ch)))
+                                               selected-channels)))
+                   ;; If the user selected this channel. Follow channel file
+                   ;; specification. Otherwise, leave the channel pinned as
+                   ;; defined by the current profile.
+                   (or selected-channel
+                       cur-ch)))
+               current-channels))))
 
   (with-error-handling
     (with-git-error-handling
      (let* ((opts         (parse-command-line args %options
-                                              (list %default-options)
-                                              #:argument-handler no-arguments))
+                                              (list %default-options)))
             (substitutes? (assoc-ref opts 'substitutes?))
             (dry-run?     (assoc-ref opts 'dry-run?))
             (profile      (or (assoc-ref opts 'profile) %current-profile))
             (current-channels (profile-channels profile))
             (validate-pull    (assoc-ref opts 'validate-pull))
             (authenticate?    (assoc-ref opts 'authenticate-channels?))
-            (verify-certificate? (assoc-ref opts 'verify-certificate?)))
+            (verify-certificate? (assoc-ref opts 'verify-certificate?))
+            (selected-channels (filter-map
+                                (match-lambda
+                                  (('argument . name) (string->symbol name))
+                                  (_ #f))
+                                opts)))
        (cond
         ((assoc-ref opts 'query)
          (process-query opts profile))
@@ -877,7 +912,9 @@ (define-command (guix-pull . args)
                  (ensure-default-profile)
                  (honor-x509-certificates store)
 
-                 (let* ((channels (channel-list opts))
+                 (let* ((channels (unpin-channels (channel-list opts)
+                                                  current-channels
+                                                  selected-channels))
                         (instances
                          (latest-channel-instances store channels
                                                    #:current-channels

base-commit: 096dedd0bb13523002c814b001429c2f65b6f10d
-- 
2.49.0