-;;; diff.el --- Run `diff' in compilation-mode.
+;;; diff.el --- run `diff' in compilation-mode
-;; Copyright (C) 1992 Free Software Foundation, Inc.
+;; Copyright (C) 1992, 1994, 1996, 2001, 2004 Free Software Foundation, Inc.
-;; Keyword: unix, tools
+;; Maintainer: FSF
+;; Keywords: unix, tools
;; This file is part of GNU Emacs.
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
-;; along with GNU Emacs; see the file COPYING. If not, write to
-;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+;; along with GNU Emacs; see the file COPYING. If not, write to the
+;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+
+;;; Commentary:
+
+;; This package helps you explore differences between files, using the
+;; UNIX command diff(1). The commands are `diff' and `diff-backup'.
+;; You can specify options with `diff-switches'.
;;; Code:
-(require 'compile)
-
-(defvar diff-switches nil
- "*A string or list of strings specifying switches to be be passed to diff.")
-
-(defvar diff-regexp-alist
- '(
- ;; -u format: @@ -OLDSTART,OLDEND +NEWSTART,NEWEND @@
- ("^@@ -\\([0-9]+\\),[0-9]+ \\+\\([0-9]+\\),[0-9]+ @@$" 1 2)
-
- ;; -c format: *** OLDSTART,OLDEND ****
- ("^\\*\\*\\* \\([0-9]+\\),[0-9]+ \\*\\*\\*\\*$" 1 nil)
- ;; --- NEWSTART,NEWEND ----
- ("^--- \\([0-9]+\\),[0-9]+ ----$" nil 1)
-
- ;; plain diff format: OLDSTART[,OLDEND]{a,d,c}NEWSTART[,NEWEND]
- ("^\\([0-9]+\\)\\(,[0-9]+\\)?[adc]\\([0-9]+\\)\\(,[0-9]+\\)?$" 1 3)
-
- ;; -e (ed) format: OLDSTART[,OLDEND]{a,d,c}
- ("^\\([0-9]+\\)\\(,[0-9]+\\)?[adc]$" 1)
-
- ;; -f format: {a,d,c}OLDSTART[ OLDEND]
- ;; -n format: {a,d,c}OLDSTART LINES-CHANGED
- ("^[adc]\\([0-9]+\\)\\( [0-9]+\\)?$" 1)
- )
- "Alist (REGEXP OLD-IDX NEW-IDX) of regular expressions to match difference
-sections in \\[diff] output. If REGEXP matches, the OLD-IDX'th
-subexpression gives the line number in the old file, and NEW-IDX'th
-subexpression gives the line number in the new file. If OLD-IDX or NEW-IDX
-is nil, REGEXP matches only half a section.")
-
-;; See compilation-parse-errors-function (compile.el).
-(defun diff-parse-differences (limit-search)
- (setq compilation-error-list nil)
- (message "Parsing differences...")
-
- ;; Don't reparse diffs already seen at last parse.
- (goto-char compilation-parsing-end)
-
- ;; Construct in REGEXP a regexp composed of all those in dired-regexp-alist.
- (let ((regexp (mapconcat (lambda (elt)
- (concat "\\(" (car elt) "\\)"))
- diff-regexp-alist
- "\\|"))
- ;; (GROUP-IDX OLD-IDX NEW-IDX)
- (groups (let ((subexpr 1))
- (mapcar (lambda (elt)
- (prog1
- (cons subexpr
- (mapcar (lambda (n)
- (and n
- (+ subexpr n)))
- (cdr elt)))
- (setq subexpr (+ subexpr 1
- (count-regexp-groupings
- (car elt))))))
- diff-regexp-alist)))
-
- (new-error
- (function (lambda (file subexpr)
- (setq compilation-error-list
- (cons
- (cons (set-marker (make-marker)
- (match-beginning subexpr)
- (current-buffer))
- (let ((line (string-to-int
- (buffer-substring
- (match-beginning subexpr)
- (match-end subexpr)))))
- (save-excursion
- (set-buffer (find-file-noselect file))
- (save-excursion
- (goto-line line)
- (point-marker)))))
- compilation-error-list)))))
-
- (found-desired nil)
- g)
-
- (while (and (not found-desired)
- ;; We don't just pass LIMIT-SEARCH to re-search-forward
- ;; because we want to find matches containing LIMIT-SEARCH
- ;; but which extend past it.
- (re-search-forward regexp nil t))
-
- ;; Find which individual regexp matched.
- (setq g groups)
- (while (and g (null (match-beginning (car (car g)))))
- (setq g (cdr g)))
- (setq g (car g))
-
- (if (nth 1 g) ;OLD-IDX
- (funcall new-error diff-old-file (nth 1 g)))
- (if (nth 2 g) ;NEW-IDX
- (funcall new-error diff-new-file (nth 2 g)))
-
- (and limit-search (>= (point) limit-search)
- ;; The user wanted a specific diff, and we're past it.
- (setq found-desired t)))
- (if found-desired
- (setq compilation-parsing-end (point))
- ;; Set to point-max, not point, so we don't perpetually
- ;; parse the last bit of text when it isn't a diff header.
- (setq compilation-parsing-end (point-max))
- (message "Parsing differences...done")))
- (setq compilation-error-list (nreverse compilation-error-list)))
+(defgroup diff nil
+ "Comparing files with `diff'."
+ :group 'tools)
+
+;;;###autoload
+(defcustom diff-switches "-c"
+ "*A string or list of strings specifying switches to be passed to diff."
+ :type '(choice string (repeat string))
+ :group 'diff)
+
+;;;###autoload
+(defcustom diff-command "diff"
+ "*The command to use to run diff."
+ :type 'string
+ :group 'diff)
+
+(defvar diff-old-temp-file nil
+ "This is the name of a temp file to be deleted after diff finishes.")
+(defvar diff-new-temp-file nil
+ "This is the name of a temp file to be deleted after diff finishes.")
+
+;; prompt if prefix arg present
+(defun diff-switches ()
+ (if current-prefix-arg
+ (read-string "Diff switches: "
+ (if (stringp diff-switches)
+ diff-switches
+ (mapconcat 'identity diff-switches " ")))))
+
+(defun diff-sentinel (code)
+ "Code run when the diff process exits.
+CODE is the exit code of the process. It should be 0 iff no diffs were found."
+ (if diff-old-temp-file (delete-file diff-old-temp-file))
+ (if diff-new-temp-file (delete-file diff-new-temp-file))
+ (save-excursion
+ (goto-char (point-max))
+ (insert (format "\nDiff finished%s. %s\n"
+ (if (equal 0 code) " (no differences)" "")
+ (current-time-string)))))
;;;###autoload
-(defun diff (old new &optional switches)
+(defun diff (old new &optional switches no-async)
"Find and display the differences between OLD and NEW files.
-Interactively the current buffer's file name is the default for for NEW
+Interactively the current buffer's file name is the default for NEW
and a backup file for NEW is the default for OLD.
+If NO-ASYNC is non-nil, call diff synchronously.
With prefix arg, prompt for diff switches."
(interactive
- (nconc
- (let (oldf newf)
- (nreverse
- (list
- (setq newf (buffer-file-name)
- newf (if (and newf (file-exists-p newf))
- (read-file-name
- (concat "Diff new file: ("
- (file-name-nondirectory newf) ") ")
- nil newf t)
- (read-file-name "Diff new file: " nil nil t)))
- (setq oldf (file-newest-backup newf)
- oldf (if (and oldf (file-exists-p oldf))
- (read-file-name
- (concat "Diff original file: ("
- (file-name-nondirectory oldf) ") ")
- (file-name-directory oldf) oldf t)
- (read-file-name "Diff original file: "
- (file-name-directory newf) nil t))))))
- (if current-prefix-arg
- (list (read-string "Diff switches: "
- (if (stringp diff-switches)
- diff-switches
- (mapconcat 'identity diff-switches " "))))
- nil)))
- (message "Comparing files %s %s..." new old)
+ (let (oldf newf)
+ (setq newf (buffer-file-name)
+ newf (if (and newf (file-exists-p newf))
+ (read-file-name
+ (concat "Diff new file: (default "
+ (file-name-nondirectory newf) ") ")
+ nil newf t)
+ (read-file-name "Diff new file: " nil nil t)))
+ (setq oldf (file-newest-backup newf)
+ oldf (if (and oldf (file-exists-p oldf))
+ (read-file-name
+ (concat "Diff original file: (default "
+ (file-name-nondirectory oldf) ") ")
+ (file-name-directory oldf) oldf t)
+ (read-file-name "Diff original file: "
+ (file-name-directory newf) nil t)))
+ (list oldf newf (diff-switches))))
(setq new (expand-file-name new)
old (expand-file-name old))
- (let ((buf (compile-internal (mapconcat 'identity
- (append '("diff")
- (if (consp diff-switches)
- diff-switches
- (list diff-switches))
- (list old)
- (list new))
- " ")
- "No more differences" "Diff"
- 'diff-parse-differences)))
+ (or switches (setq switches diff-switches)) ; If not specified, use default.
+ (let* ((old-alt (file-local-copy old))
+ (new-alt (file-local-copy new))
+ (command
+ (mapconcat 'identity
+ `(,diff-command
+ ;; Use explicitly specified switches
+ ,@(if (listp switches) switches (list switches))
+ ,@(if (or old-alt new-alt)
+ (list "-L" old "-L" new))
+ ,(shell-quote-argument (or old-alt old))
+ ,(shell-quote-argument (or new-alt new)))
+ " "))
+ (buf (get-buffer-create "*Diff*"))
+ (thisdir default-directory)
+ proc)
(save-excursion
+ (display-buffer buf)
(set-buffer buf)
- (set (make-local-variable 'diff-old-file) old)
- (set (make-local-variable 'diff-new-file) new))
+ (setq buffer-read-only nil)
+ (buffer-disable-undo (current-buffer))
+ (erase-buffer)
+ (buffer-enable-undo (current-buffer))
+ (diff-mode)
+ (set (make-local-variable 'revert-buffer-function)
+ `(lambda (ignore-auto noconfirm)
+ (diff ',old ',new ',switches ',no-async)))
+ (set (make-local-variable 'diff-old-temp-file) old-alt)
+ (set (make-local-variable 'diff-new-temp-file) new-alt)
+ (setq default-directory thisdir)
+ (insert command "\n")
+ (if (and (not no-async) (fboundp 'start-process))
+ (progn
+ (setq proc (start-process "Diff" buf shell-file-name
+ shell-command-switch command))
+ (set-process-sentinel
+ proc (lambda (proc msg)
+ (with-current-buffer (process-buffer proc)
+ (diff-sentinel (process-exit-status proc))))))
+ ;; Async processes aren't available.
+ (diff-sentinel
+ (call-process shell-file-name nil buf nil
+ shell-command-switch command))))
buf))
;;;###autoload
"Diff this file with its backup file or vice versa.
Uses the latest backup, if there are several numerical backups.
If this file is a backup, diff it with its original.
-The backup file is the first file given to `diff'."
+The backup file is the first file given to `diff'.
+With prefix arg, prompt for diff switches."
(interactive (list (read-file-name "Diff (file with backup): ")
- (if current-prefix-arg
- (read-string "Diff switches: "
- (if (stringp diff-switches)
- diff-switches
- (mapconcat 'identity
- diff-switches " ")))
- nil)))
+ (diff-switches)))
(let (bak ori)
(if (backup-file-name-p file)
(setq bak file
(defun diff-latest-backup-file (fn) ; actually belongs into files.el
"Return the latest existing backup of FILE, or nil."
- ;; First try simple backup, then the highest numbered of the
- ;; numbered backups.
- ;; Ignore the value of version-control because we look for existing
- ;; backups, which maybe were made earlier or by another user with
- ;; a different value of version-control.
- (setq fn (expand-file-name fn))
- (or
- (let ((bak (make-backup-file-name fn)))
- (if (file-exists-p bak) bak))
- (let* ((dir (file-name-directory fn))
- (base-versions (concat (file-name-nondirectory fn) ".~"))
- (bv-length (length base-versions)))
- (concat dir
- (car (sort
- (file-name-all-completions base-versions dir)
- ;; bv-length is a fluid var for backup-extract-version:
- (function
- (lambda (fn1 fn2)
- (> (backup-extract-version fn1)
- (backup-extract-version fn2))))))))))
+ (let ((handler (find-file-name-handler fn 'diff-latest-backup-file)))
+ (if handler
+ (funcall handler 'diff-latest-backup-file fn)
+ (file-newest-backup fn))))
+
+(provide 'diff)
+;;; arch-tag: 7de2c29b-7ea5-4b85-9b9d-72dd860de2bd
;;; diff.el ends here