-;;; shadow.el --- Locate Emacs Lisp file shadowings.
+;;; shadow.el --- locate Emacs Lisp file shadowings
;; Copyright (C) 1995 Free Software Foundation, Inc.
;;; Code:
\f
+(defgroup lisp-shadow nil
+ "Locate Emacs Lisp file shadowings."
+ :prefix "shadows-"
+ :group 'lisp)
+
+(defcustom shadows-compare-text-p nil
+ "*If non-nil, then shadowing files are reported only if their text differs.
+This is slower, but filters out some innocuous shadowing."
+ :type 'boolean
+ :group 'lisp-shadow)
+
(defun find-emacs-lisp-shadows (&optional path)
"Return a list of Emacs Lisp files that create shadows.
This function does the work for `list-load-path-shadows'.
are stripped from the file names in the list.
See the documentation for `list-load-path-shadows' for further information."
-
+
(or path (setq path load-path))
(let (true-names ; List of dirs considered.
files-seen-this-dir ; Files seen so far in this dir.
file) ; The current file.
-
+
(while path
- (setq dir (file-truename (or (car path) ".")))
+ (setq dir (directory-file-name (file-truename (or (car path) "."))))
(if (member dir true-names)
;; We have already considered this PATH redundant directory.
;; Show the redundancy if we are interactiver, unless the PATH
(and (car path)
(not (string= (car path) "."))
(message "Ignoring redundant directory %s" (car path))))
-
+
(setq true-names (append true-names (list dir)))
- (setq dir (or (car path) "."))
+ (setq dir (directory-file-name (or (car path) ".")))
(setq curr-files (if (file-accessible-directory-p dir)
- (directory-files dir nil ".\\.elc?$" t)))
+ (directory-files dir nil ".\\.elc?$" t)))
(and curr-files
(not noninteractive)
(message "Checking %d files in %s..." (length curr-files) dir))
-
+
(setq files-seen-this-dir nil)
(while curr-files
;; This test prevents us declaring that XXX.el shadows
;; XXX.elc (or vice-versa) when they are in the same directory.
(setq files-seen-this-dir (cons file files-seen-this-dir))
-
+
(if (setq orig-dir (assoc file files))
;; This file was seen before, we have a shadowing.
- (setq shadows
- (append shadows
- (list (concat (cdr orig-dir) "/" file)
- (concat dir "/" file))))
+ ;; Report it unless the files are identical.
+ (let ((base1 (concat (cdr orig-dir) "/" file))
+ (base2 (concat dir "/" file)))
+ (if (not (and shadows-compare-text-p
+ (shadow-same-file-or-nonexistent
+ (concat base1 ".el") (concat base2 ".el"))
+ ;; This is a bit strict, but safe.
+ (shadow-same-file-or-nonexistent
+ (concat base1 ".elc") (concat base2 ".elc"))))
+ (setq shadows
+ (append shadows (list base1 base2)))))
;; Not seen before, add it to the list of seen files.
(setq files (cons (cons file dir) files))))
;; Return the list of shadowings.
shadows))
+;; Return true if neither file exists, or if both exist and have identical
+;; contents.
+(defun shadow-same-file-or-nonexistent (f1 f2)
+ (let ((exists1 (file-exists-p f1))
+ (exists2 (file-exists-p f2)))
+ (or (and (not exists1) (not exists2))
+ (and exists1 exists2
+ (or (equal (file-truename f1) (file-truename f2))
+ ;; As a quick test, avoiding spawning a process, compare file
+ ;; sizes.
+ (and (= (nth 7 (file-attributes f1))
+ (nth 7 (file-attributes f2)))
+ (eq 0 (call-process "cmp" nil nil nil "-s" f1 f2))))))))
\f
;;;###autoload
(defun list-load-path-shadows ()
When run interactively, the shadowings \(if any\) are displayed in a
buffer called `*Shadows*'. Shadowings are located by calling the
\(non-interactive\) companion function, `find-emacs-lisp-shadows'."
-
+
(interactive)
(let* ((path (copy-sequence load-path))
(tem path)
(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.
+ ;; the last 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)))
+ (let ((break (car toplevs)))
(setq tem path)
(while tem
(if (eq (nth 1 tem) break)
(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)))))
+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))))))
(provide 'shadow)
+;;; arch-tag: 0480e8a7-62ed-4a12-a9f6-f44ded9b0830
;;; shadow.el ends here