bug#38375: 26.3.50; map-contains-key can't detect nil

[Michael Heerdegen]

Damien Cassou <damien@cassou.me> writes:

> The code below inserts the pair (nil, 'value) in a hash table. I expect
> `map-contains-key' to return t when passed the key nil as argument.
>
> (ert-deftest test-map-contains-key-with-nil-has-key-in-hashtable ()
>   (let ((map (make-hash-table :test 'equal)))
>     (puthash nil 'value map)
>     (should (map-contains-key map nil))))

This should have been fixed in master with commit 1691a5109
"*lisp/emacs-lisp/map.el: Make the functions generic".  Could you please
check?

Michael.