config/guix/profile-to-manifest: Include Guix commit

.config/guix/profile-to-manifest.scm

@@ -5,11 +5,8 @@
              (ice-9 match)
              (ice-9 pretty-print))
 
-(match (command-line)
-  ((_ where)
-   (pretty-print
-    `(specifications->manifest
-      ',(sort (map (lambda (entry)
+(define (guix-manifest where)
+  (sort (map (lambda (entry)
                      (let ((out (manifest-entry-output entry)))
                        (if (string= out "out")
                            (manifest-entry-name entry)
@@ -17,5 +14,21 @@
                                    (manifest-entry-name entry)
                                    (manifest-entry-output entry)))))
                    (manifest-entries (profile-manifest where)))
-              string<?))))
+        string<?))
+
+;; Thanks to Ivan Vilata-i-Balaguer for this:
+(define (guix-commit)
+  (let ((guix-manifest (profile-manifest (string-append (getenv "HOME") "/.config/guix/current"))))
+    (match (assq 'source (manifest-entry-properties (car (manifest-entries guix-manifest))))
+      (('source ('repository ('version 0) _ _
+                             ('commit commit) _ ...))
+       commit)
+      (_ #f))))
+
+(match (command-line)
+  ((_ where)
+   (format #t ";; commit: ~a\n" (guix-commit))
+   (pretty-print
+    `(specifications->manifest
+      ',(guix-manifest where))))
   (_ (error "Please provide the path to a Guix profile.")))