master 975acf5: Handle nil load-path element in read-library-name

[Stefan Kangas]

branch: master
commit 975acf5737248eb25900363e01d828a9c1cada64
Author: Tobias Zawada <i_inbox@tn-home.de>
Commit: Stefan Kangas <stefankangas@gmail.com>

    Handle nil load-path element in read-library-name
    
    * lisp/emacs-lisp/find-func.el (read-library-name): Fix handling of
    nil 'load-path' element.  (Bug#41998)
    
    Copyright-paperwork-exempt: yes
---
 lisp/emacs-lisp/find-func.el | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lisp/emacs-lisp/find-func.el b/lisp/emacs-lisp/find-func.el
index e35db56..56b3e32 100644
--- a/lisp/emacs-lisp/find-func.el
+++ b/lisp/emacs-lisp/find-func.el
@@ -292,12 +292,13 @@ if non-nil)."
                          (find-library-suffixes)
                          "\\|"))
          (table (cl-loop for dir in (or find-function-source-path load-path)
-                         when (file-readable-p dir)
+                         for dir-or-default = (or dir default-directory)
+                         when (file-readable-p dir-or-default)
                          append (mapcar
                                  (lambda (file)
                                    (replace-regexp-in-string suffix-regexp
                                                              "" file))
-                                 (directory-files dir nil
+                                 (directory-files dir-or-default nil
                                                   suffix-regexp))))
          (def (if (eq (function-called-at-point) 'require)
                   ;; `function-called-at-point' may return 'require