Do not signal an error when trying to delete a key from an array

* lisp/emacs-lisp/map.el (map-delete): When map is an array, check if
the key is present to avoid signaling an error.

* test/automated/map-tests.el: Add a test for deleting non-existing
keys from maps.

1 files changed, 4 insertions, 1 deletions

diff --git a/test/automated/map-tests.el b/test/automated/map-tests.el
index f41cd70c4c5..5201116613e 100644
--- a/test/automated/map-tests.el
+++ b/test/automated/map-tests.el
@@ -96,7 +96,10 @@ Evaluate BODY for each created map.
 (ert-deftest test-map-delete ()
   (with-maps-do map
     (map-delete map 1)
-    (assert (null (map-elt map 1)))))
+    (assert (null (map-elt map 1))))
+  (with-maps-do map
+    (map-delete map -2)
+    (assert (null (map-elt map -2)))))
 
 (ert-deftest test-map-delete-return-value ()
   (let ((ht (make-hash-table)))