Help Elisp xref recognize defclass parent classes

* lisp/progmodes/elisp-mode.el (elisp--xref-infer-namespace):
Handle defclass parents (bug#61640).

* test/lisp/progmodes/elisp-mode-tests.el (elisp-mode-infer-namespace):
New case in the test.

1 files changed, 5 insertions, 0 deletions

diff --git a/test/lisp/progmodes/elisp-mode-tests.el b/test/lisp/progmodes/elisp-mode-tests.el
index 57b39a49801..5b6ef88dceb 100644
--- a/test/lisp/progmodes/elisp-mode-tests.el
+++ b/test/lisp/progmodes/elisp-mode-tests.el
@@ -1004,6 +1004,11 @@ evaluation of BODY."
     (should (equal (elisp--xref-infer-namespace p6) 'function)))
 
   (elisp-mode-test--with-buffer
+      (concat "(defclass child-class ({p1}parent-1 {p2}parent-2))\n")
+    (should (equal (elisp--xref-infer-namespace p1) 'function))
+    (should (equal (elisp--xref-infer-namespace p2) 'function)))
+
+  (elisp-mode-test--with-buffer
       (concat "(require '{p1}alpha)\n"
               "(fboundp '{p2}beta)\n"
               "(boundp '{p3}gamma)\n"