master d30fde6b0c 2/3: Avoid infloops in help-fns--analyze-function with aliases

[Lars Ingebrigtsen]

branch: master
commit d30fde6b0ccc02eada1f43e0b4cc1873e42f14d2
Author: Lars Ingebrigtsen <larsi@gnus.org>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Avoid infloops in help-fns--analyze-function with aliases
    
    * lisp/help-fns.el (help-fns--analyze-function): Use
    function-alias-p to avoid infloops.
---
 lisp/help-fns.el            | 6 +-----
 test/lisp/help-fns-tests.el | 9 +++++++++
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/lisp/help-fns.el b/lisp/help-fns.el
index d408efeeb9..e000a68a82 100644
--- a/lisp/help-fns.el
+++ b/lisp/help-fns.el
@@ -829,11 +829,7 @@ Returns a list of the form (REAL-FUNCTION DEF ALIASED 
REAL-DEF)."
                                               (symbol-name function)))))))
         (real-def (cond
                     ((and aliased (not (subrp def)))
-                     (let ((f real-function))
-                       (while (and (fboundp f)
-                                   (symbolp (symbol-function f)))
-                         (setq f (symbol-function f)))
-                       f))
+                     (car (function-alias-p real-function t)))
                    ((subrp def) (intern (subr-name def)))
                     (t def))))
 
diff --git a/test/lisp/help-fns-tests.el b/test/lisp/help-fns-tests.el
index 6ee7b4f3eb..4df8e3c9ef 100644
--- a/test/lisp/help-fns-tests.el
+++ b/test/lisp/help-fns-tests.el
@@ -177,4 +177,13 @@ Return first line of the output of (describe-function-1 
FUNC)."
     (should-not (find-lisp-object-file-name help-fns--test-var 'defface))
     (should-not (find-lisp-object-file-name help-fns--test-var 1))))
 
+(ert-deftest help-fns--analyze-function-recursive ()
+  (defalias 'help-fns--a 'help-fns--b)
+  (should (equal (help-fns--analyze-function 'help-fns--a)
+                 '(help-fns--a help-fns--b t help-fns--b)))
+  ;; Make a loop and see that it doesn't infloop.
+  (defalias 'help-fns--b 'help-fns--a)
+  (should (equal (help-fns--analyze-function 'help-fns--a)
+                 '(help-fns--a help-fns--b t help-fns--b))))
+
 ;;; help-fns-tests.el ends here