database: Reset timestamps to one second after the Epoch.

Previously, store items registered in the database by this code (for
instance, store items retrieved by 'guix offload' and passed to
'restore-file-set') would have an mtime of 0 instead of 1.

This would cause problems for things like .go files: Guile would
consider them to be older than the corresponding .scm file, and
consequently it would ignore them and possibly use another (incorrect)
.go file.

Reported by Ricardo Wurmus.

* guix/store/database.scm (reset-timestamps): Pass 1, not 0, to
'utime'.
* tests/store-database.scm ("register-path"): Check the mtime of FILE
and REF.

1 files changed, 5 insertions, 2 deletions

diff --git a/tests/store-database.scm b/tests/store-database.scm
index fcae66e2de9..4d918842505 100644
--- a/tests/store-database.scm
+++ b/tests/store-database.scm
@@ -32,7 +32,8 @@
 
 (test-begin "store-database")
 
-(test-assert "register-path"
+(test-equal "register-path"
+  '(1 1)
   (let ((file (string-append (%store-prefix) "/" (make-string 32 #\f)
                              "-fake")))
     (when (valid-path? %store file)
@@ -50,7 +51,9 @@
       (and (valid-path? %store file)
            (equal? (references %store file) (list ref))
            (null? (valid-derivers %store file))
-           (null? (referrers %store file))))))
+           (null? (referrers %store file))
+           (list (stat:mtime (lstat file))
+                 (stat:mtime (lstat ref)))))))
 
 (test-equal "new database"
   (list 1 2)