[bpt/emacs.git] / lisp / diff.el

;; "DIFF" mode for handling output from unix diff utility.
;; Copyright (C) 1990 Free Software Foundation, Inc.
;; Written fpb@ittc.wec.com 1/27/89

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 1, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; 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.

;; todo: diff-switches flexibility:
;; (defconst diff-switches-function
;;   '(lambda (file)
;;     (if (string-match "\\.el$" file)
;; 	 "-c -F\"^(\""
;;       "-p"))
;;  "Function to return switches to pass to the `diff' utility, in \\[diff].
;; This function is called with one arg, a file name, and returns a string
;; containing 0 or more arguments which are passed on to `diff'.
;; NOTE: This is not an ordinary hook; it may not be a list of functions.")

;;  - fpb@ittc.wec.com - Sep 25, 1990
;; Added code to support sccs diffing.
;; also fixed one minor glitch in the
;; search for the pattern.  If you only 1 addition you won't find the end
;; of the pattern (minor)

;;
(defvar diff-switches nil
  "*A list of switches to pass to the diff program.")

(defvar diff-search-pattern "^\\([0-9]\\|\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\*\\)"
  "Regular expression that delineates difference regions in diffs.")

(defvar diff-rcs-extension ",v"
  "*Extension to find RCS file, some systems do not use ,v")

;; Initialize the keymap if it isn't already
(if (boundp 'diff-mode-map)
    nil
  (setq diff-mode-map (make-keymap))
  (suppress-keymap diff-mode-map)
  (define-key diff-mode-map "?" 'describe-mode)
  (define-key diff-mode-map "." 'diff-beginning-of-diff)
  (define-key diff-mode-map " " 'scroll-up)
  (define-key diff-mode-map "\177" 'scroll-down)
  (define-key diff-mode-map "n" 'diff-next-difference)
  (define-key diff-mode-map "p" 'diff-previous-difference)
  (define-key diff-mode-map "j" 'diff-show-difference))

;;;###autoload
(defun diff (old new)
  "Find and display the differences between OLD and NEW files.
Interactively you are prompted with the current buffer's file name for NEW
and what appears to be it's backup for OLD."
  (interactive
   (let (oldf newf)
     (reverse
      (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)))))))
  (message "Comparing files %s %s..." new old)
  (setq new (expand-file-name new)
	old (expand-file-name old))
  (diff-internal-diff "diff" (append diff-switches (list new old)) nil))

(defun diff-sccs (new)
  "Find and display the differences between OLD and SCCS files."
  (interactive
   (let (newf)
      (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))))))

  (message "Comparing SCCS file %s..." new)
  (setq new (expand-file-name new))
  (if (file-exists-p (concat
		      (file-name-directory new)
		      "SCCS/s."
		      (file-name-nondirectory new)))
      (diff-internal-diff "sccs"
			  (append '("diffs") diff-switches (list new))
			  2)
    (error "%s does not exist"
	   (concat (file-name-directory new) "SCCS/s."
		   (file-name-nondirectory new)))))

(defun diff-rcs (new)
  "Find and display the differences between OLD and RCS files."
  (interactive
   (let (newf)
      (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))))))

  (message "Comparing RCS file %s..." new)
  (let* ((fullname (expand-file-name new))
       (rcsfile (concat (file-name-directory fullname)
                       "RCS/"
                       (file-name-nondirectory fullname)
                       diff-rcs-extension)))
    (if (file-exists-p rcsfile)
      (diff-internal-diff "rcsdiff" (append diff-switches (list fullname)) 4)
      (error "%s does not exist" rcsfile))))

(defun diff-internal-diff (diff-command sw strip)
  (let ((buffer-read-only nil))
    (with-output-to-temp-buffer "*Diff Output*"
      (buffer-disable-undo standard-output)
      (save-excursion
	(set-buffer standard-output)
	(erase-buffer)
	(apply 'call-process diff-command nil t nil sw)))
    (set-buffer "*Diff Output*")
    (goto-char (point-min))
    (while sw
      (if (string= (car sw) "-c")
	  ;; strip leading filenames from context diffs
	  (progn (forward-line 2) (delete-region (point-min) (point))))
      (if (and (string= (car sw) "-C") (string= "sccs" diff-command))
	  ;; strip stuff from SCCS context diffs
	  (progn (forward-line 2) (delete-region (point-min) (point))))
      (setq sw (cdr sw)))
    (if strip
	;; strip stuff from SCCS context diffs
	(progn (forward-line strip) (delete-region (point-min) (point)))))
  (diff-mode)
  (if (string= "0" diff-total-differences)
      (let ((buffer-read-only nil))
	(insert (message "There are no differences.")))
    (narrow-to-region (point) (progn
				(forward-line 1)
				(if (re-search-forward diff-search-pattern
						       nil t)
				    (goto-char (match-beginning 0))
				  (goto-char (point-max)))))
    (setq diff-current-difference "1")))

;; Take a buffer full of Unix diff output and go into a mode to easily
;; see the next and previous difference
(defun diff-mode ()
  "Diff Mode is used by \\[diff] for perusing the output from the diff program.
All normal editing commands are turned off.  Instead, these are available:
\\<diff-mode-map>
\\[diff-beginning-of-diff]	Move point to start of this difference.
\\[scroll-up]	Scroll to next screen of this difference.
\\[scroll-down]	Scroll to previous screen of this difference.
\\[diff-next-difference]	Move to Next Difference.
\\[diff-previous-difference]	Move to Previous Difference.
\\[diff-show-difference]	Jump to difference specified by numeric position.
"
  (interactive)
  (use-local-map diff-mode-map)
  (setq buffer-read-only t
	major-mode 'diff-mode
	mode-name "Diff"
	mode-line-modified "--- "
	mode-line-process
	'(" " diff-current-difference "/" diff-total-differences))
  (make-local-variable 'diff-current-difference)
  (set (make-local-variable 'diff-total-differences)
       (int-to-string (diff-count-differences))))

(defun diff-next-difference (n)
  "Go to the beginning of the next difference.
Differences are delimited by `diff-search-pattern'."
  (interactive "p")
  (if (< n 0) (diff-previous-difference (- n))
    (if (zerop n) ()
      (goto-char (point-min))
      (forward-line 1) ; to get past the match for the start of this diff
      (widen)
      (if (re-search-forward diff-search-pattern nil 'move n)
	  (let ((start (goto-char (match-beginning 0))))
	    (forward-line 1)
	    (if (re-search-forward diff-search-pattern nil 'move)
		(goto-char (match-beginning 0)))
	    (narrow-to-region start (point))
	    (setq diff-current-difference
		  (int-to-string (+ n (string-to-int
				       diff-current-difference)))))
	(re-search-backward diff-search-pattern nil)
	(narrow-to-region (point) (point-max))
	(message "No following differences.")
	(setq diff-current-difference diff-total-differences))
      (goto-char (point-min)))))

(defun diff-previous-difference (n)
  "Go the the beginning of the previous difference.
Differences are delimited by `diff-search-pattern'."
  (interactive "p")
  (if (< n 0) (diff-next-difference (- n))
    (if (zerop n) ()
      (goto-char (point-min))
      (widen)
      (if (re-search-backward diff-search-pattern nil 'move n)
	  (setq diff-current-difference
		(int-to-string (- (string-to-int diff-current-difference) n)))
	(message "No previous differences.")
	(setq diff-current-difference "1"))
      (narrow-to-region (point) (progn
				  (forward-line 1)
				  (re-search-forward diff-search-pattern nil)
				  (goto-char (match-beginning 0))))
      (goto-char (point-min)))))

(defun diff-show-difference (n)
  "Show difference number N (prefix argument)."
  (interactive "p")
  (let ((cur (string-to-int diff-current-difference)))
    (cond ((or (= n cur)
	       (zerop n)
	       (not (natnump n))) ; should signal an error perhaps.
	   ;; just redisplay.
	   (goto-char (point-min)))
	  ((< n cur)
	   (diff-previous-difference (- cur n)))
	  ((> n cur)
	   (diff-next-difference (- n cur))))))

(defun diff-beginning-of-diff ()
  "Go to beginning of current difference."
  (interactive)
  (goto-char (point-min)))

;; This function counts up the number of differences in the buffer.
(defun diff-count-differences ()
  "Count number of differences in the current buffer."
  (message "Counting differences...")
  (save-excursion
    (save-restriction
      (widen)
      (goto-char (point-min))
      (let ((cnt 0))
	(while (re-search-forward diff-search-pattern nil t)
	  (setq cnt (1+ cnt)))
	(message "Counting differences...done (%d)" cnt)
	cnt))))
Commit	Line	Data
b10a4379 JB	1	;; "DIFF" mode for handling output from unix diff utility.
	2	;; Copyright (C) 1990 Free Software Foundation, Inc.
	3	;; Written fpb@ittc.wec.com 1/27/89
	4
	5	;; This file is part of GNU Emacs.
	6
	7	;; GNU Emacs is free software; you can redistribute it and/or modify
	8	;; it under the terms of the GNU General Public License as published by
	9	;; the Free Software Foundation; either version 1, or (at your option)
	10	;; any later version.
	11
	12	;; GNU Emacs is distributed in the hope that it will be useful,
	13	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	;; GNU General Public License for more details.
	16
	17	;; You should have received a copy of the GNU General Public License
	18	;; along with GNU Emacs; see the file COPYING. If not, write to
	19	;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
	20
	21	;; todo: diff-switches flexibility:
	22	;; (defconst diff-switches-function
	23	;; '(lambda (file)
	24	;; (if (string-match "\\.el$" file)
	25	;; "-c -F\"^(\""
	26	;; "-p"))
	27	;; "Function to return switches to pass to the `diff' utility, in \\[diff].
	28	;; This function is called with one arg, a file name, and returns a string
	29	;; containing 0 or more arguments which are passed on to `diff'.
	30	;; NOTE: This is not an ordinary hook; it may not be a list of functions.")
	31
aa228418 JB	32	;; - fpb@ittc.wec.com - Sep 25, 1990
	33	;; Added code to support sccs diffing.
	34	;; also fixed one minor glitch in the
	35	;; search for the pattern. If you only 1 addition you won't find the end
	36	;; of the pattern (minor)
	37
	38	;;
b10a4379 JB	39	(defvar diff-switches nil
	40	"*A list of switches to pass to the diff program.")
	41
	42	(defvar diff-search-pattern "^\\([0-9]\\\|\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*\\)"
	43	"Regular expression that delineates difference regions in diffs.")
	44
aa228418 JB	45	(defvar diff-rcs-extension ",v"
	46	"*Extension to find RCS file, some systems do not use ,v")
	47
b10a4379 JB	48	;; Initialize the keymap if it isn't already
	49	(if (boundp 'diff-mode-map)
	50	nil
	51	(setq diff-mode-map (make-keymap))
	52	(suppress-keymap diff-mode-map)
	53	(define-key diff-mode-map "?" 'describe-mode)
	54	(define-key diff-mode-map "." 'diff-beginning-of-diff)
	55	(define-key diff-mode-map " " 'scroll-up)
	56	(define-key diff-mode-map "\177" 'scroll-down)
	57	(define-key diff-mode-map "n" 'diff-next-difference)
	58	(define-key diff-mode-map "p" 'diff-previous-difference)
	59	(define-key diff-mode-map "j" 'diff-show-difference))
	60
	61	;;;###autoload
	62	(defun diff (old new)
	63	"Find and display the differences between OLD and NEW files.
	64	Interactively you are prompted with the current buffer's file name for NEW
	65	and what appears to be it's backup for OLD."
	66	(interactive
	67	(let (oldf newf)
	68	(reverse
	69	(list
	70	(setq newf (buffer-file-name)
	71	newf (if (and newf (file-exists-p newf))
	72	(read-file-name
	73	(concat "Diff new file: ("
	74	(file-name-nondirectory newf) ") ")
	75	nil newf t)
	76	(read-file-name "Diff new file: " nil nil t)))
	77	(setq oldf (file-newest-backup newf)
	78	oldf (if (and oldf (file-exists-p oldf))
	79	(read-file-name
	80	(concat "Diff original file: ("
	81	(file-name-nondirectory oldf) ") ")
	82	(file-name-directory oldf) oldf t)
	83	(read-file-name "Diff original file: "
	84	(file-name-directory newf) nil t)))))))
	85	(message "Comparing files %s %s..." new old)
	86	(setq new (expand-file-name new)
	87	old (expand-file-name old))
aa228418 JB	88	(diff-internal-diff "diff" (append diff-switches (list new old)) nil))
	89
	90	(defun diff-sccs (new)
	91	"Find and display the differences between OLD and SCCS files."
	92	(interactive
	93	(let (newf)
	94	(list
	95	(setq newf (buffer-file-name)
	96	newf (if (and newf (file-exists-p newf))
	97	(read-file-name
	98	(concat "Diff new file: ("
	99	(file-name-nondirectory newf) ") ")
	100	nil newf t)
	101	(read-file-name "Diff new file: " nil nil t))))))
	102
	103	(message "Comparing SCCS file %s..." new)
	104	(setq new (expand-file-name new))
	105	(if (file-exists-p (concat
	106	(file-name-directory new)
	107	"SCCS/s."
	108	(file-name-nondirectory new)))
	109	(diff-internal-diff "sccs"
	110	(append '("diffs") diff-switches (list new))
	111	2)
	112	(error "%s does not exist"
	113	(concat (file-name-directory new) "SCCS/s."
	114	(file-name-nondirectory new)))))
	115
	116	(defun diff-rcs (new)
	117	"Find and display the differences between OLD and RCS files."
	118	(interactive
	119	(let (newf)
	120	(list
	121	(setq newf (buffer-file-name)
	122	newf (if (and newf (file-exists-p newf))
	123	(read-file-name
	124	(concat "Diff new file: ("
	125	(file-name-nondirectory newf) ") ")
	126	nil newf t)
	127	(read-file-name "Diff new file: " nil nil t))))))
	128
	129	(message "Comparing RCS file %s..." new)
	130	(let* ((fullname (expand-file-name new))
	131	(rcsfile (concat (file-name-directory fullname)
	132	"RCS/"
	133	(file-name-nondirectory fullname)
	134	diff-rcs-extension)))
	135	(if (file-exists-p rcsfile)
	136	(diff-internal-diff "rcsdiff" (append diff-switches (list fullname)) 4)
	137	(error "%s does not exist" rcsfile))))
	138
	139	(defun diff-internal-diff (diff-command sw strip)
	140	(let ((buffer-read-only nil))
b10a4379 JB	141	(with-output-to-temp-buffer "Diff Output"
	142	(buffer-disable-undo standard-output)
	143	(save-excursion
	144	(set-buffer standard-output)
	145	(erase-buffer)
aa228418	146	(apply 'call-process diff-command nil t nil sw)))
b10a4379 JB	147	(set-buffer "Diff Output")
	148	(goto-char (point-min))
	149	(while sw
	150	(if (string= (car sw) "-c")
	151	;; strip leading filenames from context diffs
	152	(progn (forward-line 2) (delete-region (point-min) (point))))
aa228418 JB	153	(if (and (string= (car sw) "-C") (string= "sccs" diff-command))
	154	;; strip stuff from SCCS context diffs
	155	(progn (forward-line 2) (delete-region (point-min) (point))))
	156	(setq sw (cdr sw)))
	157	(if strip
	158	;; strip stuff from SCCS context diffs
	159	(progn (forward-line strip) (delete-region (point-min) (point)))))
b10a4379 JB	160	(diff-mode)
	161	(if (string= "0" diff-total-differences)
	162	(let ((buffer-read-only nil))
	163	(insert (message "There are no differences.")))
	164	(narrow-to-region (point) (progn
	165	(forward-line 1)
	166	(if (re-search-forward diff-search-pattern
	167	nil t)
	168	(goto-char (match-beginning 0))
	169	(goto-char (point-max)))))
	170	(setq diff-current-difference "1")))
	171
aa228418	172	;; Take a buffer full of Unix diff output and go into a mode to easily
b10a4379 JB	173	;; see the next and previous difference
	174	(defun diff-mode ()
	175	"Diff Mode is used by \\[diff] for perusing the output from the diff program.
	176	All normal editing commands are turned off. Instead, these are available:
	177	\\<diff-mode-map>
	178	\\[diff-beginning-of-diff] Move point to start of this difference.
	179	\\[scroll-up] Scroll to next screen of this difference.
	180	\\[scroll-down] Scroll to previous screen of this difference.
	181	\\[diff-next-difference] Move to Next Difference.
	182	\\[diff-previous-difference] Move to Previous Difference.
	183	\\[diff-show-difference] Jump to difference specified by numeric position.
	184	"
	185	(interactive)
	186	(use-local-map diff-mode-map)
	187	(setq buffer-read-only t
	188	major-mode 'diff-mode
	189	mode-name "Diff"
	190	mode-line-modified "--- "
	191	mode-line-process
	192	'(" " diff-current-difference "/" diff-total-differences))
	193	(make-local-variable 'diff-current-difference)
	194	(set (make-local-variable 'diff-total-differences)
	195	(int-to-string (diff-count-differences))))
	196
	197	(defun diff-next-difference (n)
aa228418 JB	198	"Go to the beginning of the next difference.
aa228418 JB	199	Differences are delimited by `diff-search-pattern'."
b10a4379 JB	200	(interactive "p")
	201	(if (< n 0) (diff-previous-difference (- n))
	202	(if (zerop n) ()
	203	(goto-char (point-min))
	204	(forward-line 1) ; to get past the match for the start of this diff
	205	(widen)
	206	(if (re-search-forward diff-search-pattern nil 'move n)
	207	(let ((start (goto-char (match-beginning 0))))
	208	(forward-line 1)
	209	(if (re-search-forward diff-search-pattern nil 'move)
	210	(goto-char (match-beginning 0)))
	211	(narrow-to-region start (point))
	212	(setq diff-current-difference
	213	(int-to-string (+ n (string-to-int
	214	diff-current-difference)))))
	215	(re-search-backward diff-search-pattern nil)
	216	(narrow-to-region (point) (point-max))
	217	(message "No following differences.")
	218	(setq diff-current-difference diff-total-differences))
	219	(goto-char (point-min)))))
	220
	221	(defun diff-previous-difference (n)
aa228418 JB	222	"Go the the beginning of the previous difference.
aa228418 JB	223	Differences are delimited by `diff-search-pattern'."
b10a4379 JB	224	(interactive "p")
	225	(if (< n 0) (diff-next-difference (- n))
	226	(if (zerop n) ()
	227	(goto-char (point-min))
	228	(widen)
	229	(if (re-search-backward diff-search-pattern nil 'move n)
	230	(setq diff-current-difference
	231	(int-to-string (- (string-to-int diff-current-difference) n)))
	232	(message "No previous differences.")
	233	(setq diff-current-difference "1"))
	234	(narrow-to-region (point) (progn
	235	(forward-line 1)
	236	(re-search-forward diff-search-pattern nil)
	237	(goto-char (match-beginning 0))))
	238	(goto-char (point-min)))))
	239
	240	(defun diff-show-difference (n)
aa228418	241	"Show difference number N (prefix argument)."
b10a4379 JB	242	(interactive "p")
	243	(let ((cur (string-to-int diff-current-difference)))
	244	(cond ((or (= n cur)
	245	(zerop n)
	246	(not (natnump n))) ; should signal an error perhaps.
	247	;; just redisplay.
	248	(goto-char (point-min)))
	249	((< n cur)
	250	(diff-previous-difference (- cur n)))
	251	((> n cur)
	252	(diff-next-difference (- n cur))))))
	253
	254	(defun diff-beginning-of-diff ()
	255	"Go to beginning of current difference."
	256	(interactive)
	257	(goto-char (point-min)))
	258
	259	;; This function counts up the number of differences in the buffer.
	260	(defun diff-count-differences ()
	261	"Count number of differences in the current buffer."
	262	(message "Counting differences...")
	263	(save-excursion
	264	(save-restriction
	265	(widen)
	266	(goto-char (point-min))
	267	(let ((cnt 0))
	268	(while (re-search-forward diff-search-pattern nil t)
	269	(setq cnt (1+ cnt)))
	270	(message "Counting differences...done (%d)" cnt)
	271	cnt))))