fix/bug-39491 06cdc95: * lisp/battery.el (battery-upower): Produce an empty string if level is nil

[Nicolas Richard]

branch: fix/bug-39491
commit 06cdc95cba8a3cd7048f373767267400c7837132
Author: Nicolas Richard <address@hidden>
Commit: Nicolas Richard <address@hidden>

    * lisp/battery.el (battery-upower): Produce an empty string if level is nil
---
 lisp/battery.el | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lisp/battery.el b/lisp/battery.el
index 7027b25..d441f15 100644
--- a/lisp/battery.el
+++ b/lisp/battery.el
@@ -656,7 +656,8 @@ The following %-sequences are provided:
           (cons ?B (if state
                        (cdr (assq state battery-upower-states))
                      "unknown"))
-          (cons ?b (cond ((= level 3) "-")
+          (cons ?b (cond ((not level) "")
+                         ((= level 3) "-")
                          ((= level 4) "!")
                          (online-p "+")
                          (t "")))