ui: Fix not finding compiled files when loading extensions

The Guix command load machinery was using 'load' with an absolute file name
which meant that the compiled file would be searched under directories from
'GUILE_LOAD_COMPILED_PATH' using the absolute paths.

For example: Given 'GUILE_LOAD_COMPILED_PATH=/path/to/site-ccache'

'/<example>/guix/extensions/foo.scm' would be searched under
'/path/to/site-ccache//<example>/guix/extensions/foo.scm', rather than
''/path/to/site-ccache/guix/extensions/foo.scm'.

* guix/ui.scm (run-guix-command): Use 'resolve-interface' rather than 'load'
with an absolute path to ensure that the compiled files can be found
'GUILE_LOAD_COMPILED_PATH' without the absolute path appended.
(run-guix): Augment '%load-path' with GUIX_EXTENSIONS_PATH so extensions can
be found using 'resolve-interface' rather than 'load' with an absolute path.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>
Merges: #10607

1 files changed, 14 insertions, 20 deletions

diff --git a/guix/ui.scm b/guix/ui.scm
index dafc04b20f7..78a58e353e1 100644
--- a/guix/ui.scm
+++ b/guix/ui.scm
@@ -2447,26 +2447,17 @@ found."
 
   (define module
     ;; Check if there is a matching extension.
-    (match (search-path (extension-directories)
-                        (format #f "~a.scm" command))
-      (#f
-       (catch 'misc-error
-         (lambda ()
-           (resolve-interface `(guix scripts ,command)))
-         (lambda _
-           (let ((hint (command-hint command (commands))))
-             (format (current-error-port)
-                     (G_ "guix: ~a: command not found~%") command)
-             (when hint
-               (display-hint (G_ "Did you mean @code{~a}?") hint))
-             (show-guix-usage)))))
-      (file
-       (load file)
-       (let ((maybe-extension-path
-              (format #f "/guix/extensions/~a.scm" command)))
-         (if (string-suffix? maybe-extension-path file)
-             (resolve-interface `(guix extensions ,command))
-             (resolve-interface `(guix scripts ,command)))))))
+    (catch 'misc-error
+      (lambda ()
+        (or (false-if-exception (resolve-interface `(guix scripts ,command)))
+            (resolve-interface `(guix extensions ,command))))
+      (lambda _
+        (let ((hint (command-hint command (commands))))
+          (format (current-error-port)
+                  (G_ "guix: ~a: command not found~%") command)
+          (when hint
+            (display-hint (G_ "Did you mean @code{~a}?") hint))
+          (show-guix-usage)))))
 
   (let ((command-main (module-ref module
                                   (symbol-append 'guix- command))))
@@ -2490,6 +2481,9 @@ and signal handling have already been set up."
   ;; number of 'stat' calls per entry in %LOAD-PATH.  Shamelessly remove it.
   (set! %load-extensions '(".scm"))
 
+  ;; Extensions take precedence over core commands.
+  (set! %load-path (append (extension-directories) %load-path))
+
   ;; Disable canonicalization so we don't don't stat unreasonably.
   (with-fluids ((%file-port-name-canonicalization #f))
     (match args