-;;; flow-fill.el --- interprete RFC2646 "flowed" text
+;;; flow-fill.el --- interpret RFC2646 "flowed" text
-;; Copyright (C) 2000 Free Software Foundation, Inc.
+;; Copyright (C) 2000-2011 Free Software Foundation, Inc.
;; Author: Simon Josefsson <jas@pdc.kth.se>
;; Keywords: mail
;; This file is part of GNU Emacs.
-;; GNU Emacs is free software; you can redistribute it and/or modify
+;; 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 2, or (at your option)
-;; any later version.
+;; the Free Software Foundation, either version 3 of the License, 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
;; 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, Inc., 59 Temple Place - Suite 330,
-;; Boston, MA 02111-1307, USA.
+;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;; paragraph and we let `fill-region' fill the long line into several
;; lines with the quote prefix as `fill-prefix'.
-;; Todo: encoding, implement basic `fill-region' (Emacs and XEmacs
+;; Todo: implement basic `fill-region' (Emacs and XEmacs
;; implementations differ..)
-;; History:
+;;; History:
;; 2000-02-17 posted on ding mailing list
;; 2000-02-19 use `point-at-{b,e}ol' in XEmacs
;; 2000-03-11 no compile warnings for point-at-bol stuff
-;; 2000-03-26 commited to gnus cvs
+;; 2000-03-26 committed to gnus cvs
;; 2000-10-23 don't flow "-- " lines, make "quote-depth wins" rule
;; work when first line is at level 0.
+;; 2002-01-12 probably incomplete encoding support
+;; 2003-12-08 started working on test harness.
;;; Code:
(eval-when-compile (require 'cl))
-(eval-and-compile
- (defalias 'fill-flowed-point-at-bol
- (if (fboundp 'point-at-bol)
- 'point-at-bol
- 'line-beginning-position))
-
- (defalias 'fill-flowed-point-at-eol
- (if (fboundp 'point-at-eol)
- 'point-at-eol
- 'line-end-position)))
-
-(defun fill-flowed (&optional buffer)
- (save-excursion
- (set-buffer (or (current-buffer) buffer))
+(defcustom fill-flowed-display-column 'fill-column
+ "Column beyond which format=flowed lines are wrapped, when displayed.
+This can be a Lisp expression or an integer."
+ :version "22.1"
+ :group 'mime-display
+ :type '(choice (const :tag "Standard `fill-column'" fill-column)
+ (const :tag "Fit Window" (- (window-width) 5))
+ (sexp)
+ (integer)))
+
+(defcustom fill-flowed-encode-column 66
+ "Column beyond which format=flowed lines are wrapped, in outgoing messages.
+This can be a Lisp expression or an integer.
+RFC 2646 suggests 66 characters for readability."
+ :version "22.1"
+ :group 'mime-display
+ :type '(choice (const :tag "Standard fill-column" fill-column)
+ (const :tag "RFC 2646 default (66)" 66)
+ (sexp)
+ (integer)))
+
+;;;###autoload
+(defun fill-flowed-encode (&optional buffer)
+ (with-current-buffer (or buffer (current-buffer))
+ ;; No point in doing this unless hard newlines is used.
+ (when use-hard-newlines
+ (let ((start (point-min)) end)
+ ;; Go through each paragraph, filling it and adding SPC
+ ;; as the last character on each line.
+ (while (setq end (text-property-any start (point-max) 'hard 't))
+ (save-restriction
+ (narrow-to-region start end)
+ (let ((fill-column (eval fill-flowed-encode-column)))
+ (fill-flowed-fill-buffer))
+ (goto-char (point-min))
+ (while (re-search-forward "\n" nil t)
+ (replace-match " \n" t t))
+ (goto-char (setq start (1+ (point-max)))))))
+ t)))
+
+(defun fill-flowed-fill-buffer ()
+ (let ((prefix nil)
+ (prev-prefix nil)
+ (start (point-min)))
+ (goto-char (point-min))
+ (while (not (eobp))
+ (setq prefix (and (looking-at "[> ]+")
+ (match-string 0)))
+ (if (equal prefix prev-prefix)
+ (forward-line 1)
+ (save-restriction
+ (narrow-to-region start (point))
+ (let ((fill-prefix prev-prefix))
+ (fill-region (point-min) (point-max) t 'nosqueeze 'to-eop))
+ (goto-char (point-max)))
+ (setq prev-prefix prefix
+ start (point))))
+ (save-restriction
+ (narrow-to-region start (point))
+ (let ((fill-prefix prev-prefix))
+ (fill-region (point-min) (point-max) t 'nosqueeze 'to-eop)))))
+
+;;;###autoload
+(defun fill-flowed (&optional buffer delete-space)
+ (with-current-buffer (or (current-buffer) buffer)
+ (goto-char (point-min))
+ ;; Remove space stuffing.
+ (while (re-search-forward "^\\( \\|>+ $\\)" nil t)
+ (delete-char -1)
+ (forward-line 1))
(goto-char (point-min))
(while (re-search-forward " $" nil t)
(when (save-excursion
(beginning-of-line)
(looking-at "^\\(>*\\)\\( ?\\)"))
- (let ((quote (match-string 1)) sig)
+ (let ((quote (match-string 1))
+ sig)
(if (string= quote "")
(setq quote nil))
(when (and quote (string= (match-string 2) ""))
(beginning-of-line)
(when (> (skip-chars-forward ">") 0)
(insert " "))))
+ ;; XXX slightly buggy handling of "-- "
(while (and (save-excursion
(ignore-errors (backward-char 3))
(setq sig (looking-at "-- "))
(save-excursion
(unless (eobp)
(forward-char 1)
- (looking-at (format "^\\(%s\\)\\([^>]\\)" (or quote " ?"))))))
+ (looking-at (format "^\\(%s\\)\\([^>\n\r]\\)"
+ (or quote " ?"))))))
(save-excursion
(replace-match (if (string= (match-string 2) " ")
"" "\\2")))
(backward-delete-char -1)
+ (when delete-space
+ (delete-char -1))
(end-of-line))
(unless sig
- (let ((fill-prefix (when quote (concat quote " "))))
- (fill-region (fill-flowed-point-at-bol)
- (fill-flowed-point-at-eol)
- 'left 'nosqueeze)
-
- (when (looking-at "^$")
- (kill-line)))))))))
+ (condition-case nil
+ (let ((fill-prefix (when quote (concat quote " ")))
+ (fill-column (eval fill-flowed-display-column))
+ filladapt-mode
+ adaptive-fill-mode)
+ (fill-region (point-at-bol)
+ (min (1+ (point-at-eol))
+ (point-max))
+ 'left 'nosqueeze))
+ (error
+ (forward-line 1)
+ nil))))))))
+
+;; Test vectors.
+
+(defvar show-trailing-whitespace)
+
+(defvar fill-flowed-encode-tests
+ `(
+ ;; The syntax of each list element is:
+ ;; (INPUT . EXPECTED-OUTPUT)
+ (,(concat
+ "> Thou villainous ill-breeding spongy dizzy-eyed \n"
+ "> reeky elf-skinned pigeon-egg! \n"
+ ">> Thou artless swag-bellied milk-livered \n"
+ ">> dismal-dreaming idle-headed scut!\n"
+ ">>> Thou errant folly-fallen spleeny reeling-ripe \n"
+ ">>> unmuzzled ratsbane!\n"
+ ">>>> Henceforth, the coding style is to be strictly \n"
+ ">>>> enforced, including the use of only upper case.\n"
+ ">>>>> I've noticed a lack of adherence to the coding \n"
+ ">>>>> styles, of late.\n"
+ ">>>>>> Any complaints?")
+ .
+ ,(concat
+ "> Thou villainous ill-breeding spongy dizzy-eyed reeky elf-skinned\n"
+ "> pigeon-egg! \n"
+ ">> Thou artless swag-bellied milk-livered dismal-dreaming idle-headed\n"
+ ">> scut!\n"
+ ">>> Thou errant folly-fallen spleeny reeling-ripe unmuzzled ratsbane!\n"
+ ">>>> Henceforth, the coding style is to be strictly enforced,\n"
+ ">>>> including the use of only upper case.\n"
+ ">>>>> I've noticed a lack of adherence to the coding styles, of late.\n"
+ ">>>>>> Any complaints?\n"
+ ))
+ ;; (,(concat
+ ;; "\n"
+ ;; "> foo\n"
+ ;; "> \n"
+ ;; "> \n"
+ ;; "> bar\n")
+ ;; .
+ ;; ,(concat
+ ;; "\n"
+ ;; "> foo bar\n"))
+ ))
+
+(defun fill-flowed-test ()
+ (interactive "")
+ (switch-to-buffer (get-buffer-create "*Format=Flowed test output*"))
+ (erase-buffer)
+ (setq show-trailing-whitespace t)
+ (dolist (test fill-flowed-encode-tests)
+ (let (start output)
+ (insert "***** BEGIN TEST INPUT *****\n")
+ (insert (car test))
+ (insert "***** END TEST INPUT *****\n\n")
+ (insert "***** BEGIN TEST OUTPUT *****\n")
+ (setq start (point))
+ (insert (car test))
+ (save-restriction
+ (narrow-to-region start (point))
+ (fill-flowed))
+ (setq output (buffer-substring start (point-max)))
+ (insert "***** END TEST OUTPUT *****\n")
+ (unless (string= output (cdr test))
+ (insert "\n***** BEGIN TEST EXPECTED OUTPUT *****\n")
+ (insert (cdr test))
+ (insert "***** END TEST EXPECTED OUTPUT *****\n"))
+ (insert "\n\n")))
+ (goto-char (point-max)))
(provide 'flow-fill)