;;; diff.el --- Run `diff' in compilation-mode.
-;; Copyright (C) 1992 Free Software Foundation, Inc.
+;; Copyright (C) 1992, 1994, 1996 Free Software Foundation, Inc.
-;; Keyword: unix, tools
+;; 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
+;;; This is duplicated in vc.el.
+(defvar diff-switches "-c"
"*A string or list of strings specifying switches to be be passed to diff.")
+(defvar diff-command "diff"
+ "*The command to use to run 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
+ "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.")
+(defvar diff-old-file nil
+ "This is the old file name in the comparison in this buffer.")
+(defvar diff-new-file nil
+ "This is the new file name in the comparison in this buffer.")
+(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.")
+
;; See compilation-parse-errors-function (compile.el).
(defun diff-parse-differences (limit-search find-at-least)
(setq compilation-error-list nil)
(message "Parsing differences...")
;; Don't reparse diffs already seen at last parse.
- (goto-char compilation-parsing-end)
+ (if compilation-parsing-end (goto-char compilation-parsing-end))
;; Construct in REGEXP a regexp composed of all those in dired-regexp-alist.
(let ((regexp (mapconcat (lambda (elt)
(function (lambda (file subexpr)
(setq compilation-error-list
(cons
- (cons (set-marker (make-marker)
- (match-beginning subexpr)
- (current-buffer))
+ (cons (save-excursion
+ ;; Report location of message
+ ;; at beginning of line.
+ (goto-char
+ (match-beginning subexpr))
+ (beginning-of-line)
+ (point-marker))
+ ;; Report location of corresponding text.
(let ((line (string-to-int
(buffer-substring
(match-beginning subexpr)
(match-end subexpr)))))
(save-excursion
- (set-buffer (find-file-noselect file))
+ (save-match-data
+ (set-buffer (find-file-noselect file)))
(save-excursion
(goto-line line)
(point-marker)))))
compilation-error-list)))))
(found-desired nil)
+ (num-loci-found 0)
g)
(while (and (not found-desired)
(if (nth 2 g) ;NEW-IDX
(funcall new-error diff-new-file (nth 2 g)))
- (if (or (and find-at-least (>= nfound find-at-least))
+ (setq num-loci-found (1+ num-loci-found))
+ (if (or (and find-at-least
+ (>= num-loci-found find-at-least))
(and limit-search (>= (point) limit-search)))
- ;; We have found as many new errors as the user wants,
+ ;; 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))
- (message "Parsing differences...done")))
+ (setq compilation-parsing-end (point-max)))
+ (message "Parsing differences...done"))
(setq compilation-error-list (nreverse compilation-error-list)))
;;;###autoload
(defun diff (old new &optional switches)
"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.
With prefix arg, prompt for diff switches."
(interactive
diff-switches
(mapconcat 'identity diff-switches " "))))
nil)))
- (message "Comparing files %s %s..." new old)
(setq new (expand-file-name new)
old (expand-file-name old))
- (let ((old-alt (diff-prepare old new))
- (new-alt (diff-prepare new old))
+ (let ((old-alt (file-local-copy old))
+ (new-alt (file-local-copy new))
buf)
(unwind-protect
(let ((command
(mapconcat 'identity
- (append '("diff")
- (if (consp diff-switches)
- diff-switches
- (list diff-switches))
+ (append (list diff-command)
+ ;; Use explicitly specified switches
+ (if switches
+ (if (consp switches)
+ switches (list switches))
+ ;; If not specified, use default.
+ (if (consp diff-switches)
+ diff-switches
+ (list diff-switches)))
(if (or old-alt new-alt)
(list "-L" old "-L" new))
- (list (or old-alt old))
- (list (or new-alt new)))
+ (list
+ (shell-quote-argument (or old-alt old)))
+ (list
+ (shell-quote-argument (or new-alt new))))
" ")))
(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))
- buf)
- (if old-alt (delete-file old-alt))
- (if new-alt (delete-file new-alt)))))
-
-;; Copy the file FILE into a temporary file if that is necessary
-;; for comparison. (This is only necessary if the file name has a handler.)
-;; OTHER is the other file to be compared.
-(defun diff-prepare (file other)
- (let (handler handlers)
- (setq handlers file-name-handler-alist)
- (while (and (consp handlers) (null handler))
- (if (and (consp (car handlers))
- (stringp (car (car handlers)))
- (string-match (car (car handlers)) file))
- (setq handler (cdr (car handlers))))
- (setq handlers (cdr handlers)))
- (if handler
- (funcall handler 'diff-prepare file other)
- nil)))
+ (pop-to-buffer buf)
+ ;; 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)))))
+ (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)))))
+ buf))))
;;;###autoload
(defun diff-backup (file &optional switches)
(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)
+ ;; 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 (file-chase-links (expand-file-name fn)))
+ (or
+ (let ((bak (make-backup-file-name fn)))
+ (if (file-exists-p bak) bak))
+ ;; We use BACKUPNAME to cope with backups stored in a different dir.
+ (let* ((backupname (car (find-backup-file-name fn)))
+ (dir (file-name-directory backupname))
+ (base-versions (concat (file-name-sans-versions
+ (file-name-nondirectory backupname))
+ ".~"))
+ (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))))))))))))
+
+(provide 'diff)
;;; diff.el ends here