(list-load-path-shadows): Exclude, from the path we search, all but

the first set of directories that include the standard Emacs Lisp files.

diff --git a/lisp/emacs-lisp/shadow.el b/lisp/emacs-lisp/shadow.el
index 7e49c8b6f174093914b4377490aa83371ab6802e..cca8b350731c986e8b87d70624014149d6076e61 100644 (file)
--- a/lisp/emacs-lisp/shadow.el
+++ b/lisp/emacs-lisp/shadow.el
@@ -173,34 +173,56 @@ buffer called `*Shadows*'.  Shadowings are located by calling the
 \(non-interactive\) companion function, `find-emacs-lisp-shadows'."
   
   (interactive)
-  (let* ((shadows (find-emacs-lisp-shadows))
-        (n (/ (length shadows) 2))
-        (msg (format "%s Emacs Lisp load-path shadowing%s found"
-                     (if (zerop n) "No" (concat "\n" (number-to-string n)))
-                     (if (= n 1) " was" "s were"))))
-    (if (interactive-p)
-       (save-excursion
-         ;; We are interactive.
-         ;; Create the *Shadows* buffer and display shadowings there.
-         (let ((output-buffer (get-buffer-create "*Shadows*")))
-           (display-buffer output-buffer)
-           (set-buffer output-buffer)
-           (erase-buffer)
-           (while shadows
-             (insert (format "%s hides %s\n" (car shadows)
-                             (car (cdr shadows))))
-             (setq shadows (cdr (cdr shadows))))
-           (insert msg "\n")))
-      ;; We are non-interactive, print shadows via message.
-      (when shadows
-       (message "This site has duplicate Lisp libraries with the same name.
+  (let* ((path (copy-sequence load-path))
+       (tem path)
+       toplevs)
+    ;; If we can find simple.el in two places,
+    (while tem
+      (if (file-exists-p (expand-file-name "simple.el" (car tem)))
+         (setq toplevs (cons (car tem) toplevs)))
+      (setq tem (cdr tem)))
+    (if (> (length toplevs) 1)
+       ;; Cut off our copy of load-path right before
+       ;; the second directory which has simple.el in it.
+       ;; This avoids loads of duplications between the source dir
+       ;; and the dir where these files were copied by installation.
+       (let ((break (nth (- (length toplevs) 2) toplevs)))
+         (setq tem path)
+         (while tem
+           (if (eq (nth 1 tem) break)
+               (progn
+                 (setcdr tem nil)
+                 (setq tem nil)))
+           (setq tem (cdr tem)))))
+
+    (let* ((shadows (find-emacs-lisp-shadows path))
+          (n (/ (length shadows) 2))
+          (msg (format "%s Emacs Lisp load-path shadowing%s found"
+                       (if (zerop n) "No" (concat "\n" (number-to-string n)))
+                       (if (= n 1) " was" "s were"))))
+      (if (interactive-p)
+         (save-excursion
+           ;; We are interactive.
+           ;; Create the *Shadows* buffer and display shadowings there.
+           (let ((output-buffer (get-buffer-create "*Shadows*")))
+             (display-buffer output-buffer)
+             (set-buffer output-buffer)
+             (erase-buffer)
+             (while shadows
+               (insert (format "%s hides %s\n" (car shadows)
+                               (car (cdr shadows))))
+               (setq shadows (cdr (cdr shadows))))
+             (insert msg "\n")))
+       ;; We are non-interactive, print shadows via message.
+       (when shadows
+         (message "This site has duplicate Lisp libraries with the same name.
 If a locally-installed Lisp library overrides a library in the Emacs release,
 that can cause trouble, and you should probably remove the locally-installed
 version unless you know what you are doing.\n"))
-      (while shadows
-       (message "%s hides %s" (car shadows) (car (cdr shadows)))
-       (setq shadows (cdr (cdr shadows))))
-      (message "%s" msg))))
+       (while shadows
+         (message "%s hides %s" (car shadows) (car (cdr shadows)))
+         (setq shadows (cdr (cdr shadows))))
+       (message "%s" msg)))))
 
 (provide 'shadow)