-;;; 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 Free Software Foundation, Inc.
+;; 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:
(require 'compile)
-;;; This is duplicated in vc.el.
-(defvar diff-switches "-c"
- "*A string or list of strings specifying switches to be be passed to diff.")
+(defgroup diff nil
+ "Comparing files with `diff'."
+ :group 'tools)
+
+;;;###autoload
+(defcustom diff-switches "-c"
+ "*A string or list of strings specifying switches to be 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-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 ----
;; -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.")
+ "Alist of regular expressions to match difference sections in \\[diff] output.
+Each element has the form (REGEXP OLD-IDX NEW-IDX).
+Any text that REGEXP matches identifies one difference hunk
+or the header of a hunk.
+
+The OLD-IDX'th subexpression of REGEXP 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 hunk.")
(defvar diff-old-file nil
"This is the old file name in the comparison in this buffer.")
;; We have found as many new loci as the user wants,
;; or 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)))
+ (set-marker compilation-parsing-end
+ (if found-desired (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.
+ (point-max)))
(message "Parsing differences...done"))
(setq compilation-error-list (nreverse compilation-error-list)))
+(defun diff-process-setup ()
+ "Set up \`compilation-exit-message-function' for \`diff'."
+ ;; Avoid frightening people with "abnormally terminated"
+ ;; if diff finds differences.
+ (set (make-local-variable 'compilation-exit-message-function)
+ (lambda (status code msg)
+ (cond ((not (eq status 'exit))
+ (cons msg code))
+ ((zerop code)
+ '("finished (no differences)\n" . "no differences"))
+ ((= code 1)
+ '("finished\n" . "differences found"))
+ (t
+ (cons msg code))))))
+
;;;###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 NEW
and a backup file for NEW is the default for OLD.
-With prefix arg, prompt for diff switches."
+With prefix arg, prompt for diff switches.
+If NO-ASYNC is non-nil, call diff synchronously."
(interactive
(nconc
(let (oldf newf)
(setq newf (buffer-file-name)
newf (if (and newf (file-exists-p newf))
(read-file-name
- (concat "Diff new file: ("
+ (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: ("
+ (concat "Diff original file: (default "
(file-name-nondirectory oldf) ") ")
(file-name-directory oldf) oldf t)
(read-file-name "Diff original file: "
(let ((old-alt (file-local-copy old))
(new-alt (file-local-copy new))
buf)
- (unwind-protect
- (let ((command
+ (save-excursion
+ (let ((compilation-process-setup-function 'diff-process-setup)
+ (command
(mapconcat 'identity
- (append '("diff")
+ (append (list diff-command)
;; Use explicitly specified switches
(if switches
(if (consp switches)
(setq buf
(compile-internal command
"No more differences" "Diff"
- 'diff-parse-differences))
- (save-excursion
- (set-buffer buf)
- (set (make-local-variable 'diff-old-file) old)
- (set (make-local-variable 'diff-new-file) new)
- (set (make-local-variable 'diff-old-temp-file) old-alt)
- (set (make-local-variable 'diff-new-temp-file) new-alt)
- (set (make-local-variable 'compilation-finish-function)
- (function (lambda (buff msg)
- (if diff-old-temp-file
- (delete-file diff-old-temp-file))
- (if diff-new-temp-file
- (delete-file diff-new-temp-file))))))
+ 'diff-parse-differences
+ nil nil nil nil nil nil no-async))
+ (set-buffer buf)
+ (set (make-local-variable 'diff-old-file) old)
+ (set (make-local-variable 'diff-new-file) new)
+ (set (make-local-variable 'diff-old-temp-file) old-alt)
+ (set (make-local-variable 'diff-new-temp-file) new-alt)
+ (set (make-local-variable 'compilation-finish-function)
+ (function (lambda (buff msg)
+ (if diff-old-temp-file
+ (delete-file diff-old-temp-file))
+ (if diff-new-temp-file
+ (delete-file diff-new-temp-file)))))
+ ;; When async processes aren't available, the compilation finish
+ ;; function doesn't get chance to run. Invoke it by hand.
+ (or (fboundp 'start-process)
+ (funcall compilation-finish-function nil nil))
buf))))
;;;###autoload
(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