tests: Add test to validate /etc/locatime is a symlink.

Match the modern desktop expectation set by systemd [0] and relied on by some
software (GNOME/glib, icecat, ungoogle-chromium, etc.).

[0]  https://www.man7.org/linux/man-pages/man5/localtime.5.html

* gnu/tests/base.scm
("/etc/localtime is a symlink to the timezone data file"): New test.

Change-Id: I8fb95abb6a3e455dd7019d5d798f7862d16b6263
Reviewed-by: Ludovic Courtès <ludo@gnu.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/gnu/tests/base.scm b/gnu/tests/base.scm
index 659b754802f..dc51880d8ed 100644
--- a/gnu/tests/base.scm
+++ b/gnu/tests/base.scm
@@ -232,6 +232,18 @@ info --version")
                `(tm:gmtoff (localtime ,sept-2021))
                marionette)))
 
+          (test-equal "/etc/localtime is a symlink to the timezone data file"
+            ;; This is a systemd-ism that most distributions follow; we do to,
+            ;; for compatibility with software that assumes this is convention
+            ;; is followed (see:
+            ;; <https://www.freedesktop.org/software/systemd/man/latest/localtime.html#>)
+            #$(operating-system-timezone os)
+            (marionette-eval
+             `(string-join
+               (take-right (string-split (readlink "/etc/localtime") #\/) 2)
+               "/")
+             marionette))
+
           (test-equal "/var/log/messages is not world-readable"
             #o640                       ;<https://bugs.gnu.org/40405>
             (begin