canonically-space-region and fill-delete-newlines leave bounds

[Nikolaj Schumacher]

Hello,

`canonically-space-region' doesn't stop at the end of the region.
That's because it limits its searches at `end', while the actual region
keeps getting smaller.

For example:
a                                     b
c   d
Mark the first line, call `canonically-space-region' and observe that
the spaces in the second line disappear as well.

`fill-delete-newlines' has the same problem because it calls
`canonically-space-region' and because it uses the `to' variable
afterwards.

A proposed patch is attached.


regards,
Nikolaj Schumacher

diff -du 
/Users/nik/.emacs.d/backup/\!Applications\!Emacs.app\!Contents\!Resources\!share\!emacs\!22.1.50\!lisp\!textmodes\!fill.el.\~1\~
 
/Applications/Emacs.app/Contents/Resources/share/emacs/22.1.50/lisp/textmodes/fill.el
--- lisp/textmodes/fill.el      2007-04-27 15:28:14.000000000 +0200
+++ lisp/textmodes/fill.el      2007-05-24 14:28:23.000000000 +0200
@@ -159,7 +159,8 @@
 and `sentence-end-without-period').
 Remove indentation from each line."
   (interactive "*r")
-  (let ((end-spc-re (concat "\\(" (sentence-end) "\\) *\\|  +")))
+  (let ((end-spc-re (concat "\\(" (sentence-end) "\\) *\\|  +"))
+       delete-begin delete-end)
     (save-excursion
       (goto-char beg)
       ;; Nuke tabs; they get screwed up in a fill.
@@ -169,35 +170,41 @@
       (subst-char-in-region beg end ?\t ?\s)
       (while (and (< (point) end)
                  (re-search-forward end-spc-re end t))
-       (delete-region
-        (cond
-         ;; `sentence-end' matched and did not match all spaces.
-         ;; I.e. it only matched the number of spaces it needs: drop the rest.
-         ((and (match-end 1) (> (match-end 0) (match-end 1)))  (match-end 1))
-         ;; `sentence-end' matched but with nothing left.  Either that means
-         ;; nothing should be removed, or it means it's the "old-style"
-         ;; sentence-end which matches all it can.  Keep only 2 spaces.
-         ;; We probably don't even need to check `sentence-end-double-space'.
-         ((match-end 1)
-          (min (match-end 0)
-               (+ (if sentence-end-double-space 2 1)
-                  (save-excursion (goto-char (match-end 0))
-                                  (skip-chars-backward " ")
-                                  (point)))))
-         (t ;; It's not an end of sentence.
-          (+ (match-beginning 0)
-             ;; Determine number of spaces to leave:
-             (save-excursion
-               (skip-chars-backward " ]})\"'")
-               (cond ((and sentence-end-double-space
-                           (or (memq (preceding-char) '(?. ?? ?!))
-                               (and sentence-end-without-period
-                                    (= (char-syntax (preceding-char)) ?w)))) 2)
-                     ((and colon-double-space
-                           (= (preceding-char) ?:))  2)
-                     ((char-equal (preceding-char) ?\n)  0)
-                     (t 1))))))
-        (match-end 0))))))
+       (setq delete-begin
+             (cond
+              ;; `sentence-end' matched and did not match all spaces.  I.e. it
+              ;; only matched the number of spaces it needs: drop the rest.
+              ((and (match-end 1) (> (match-end 0) (match-end 1)))
+               (match-end 1))
+              ;; `sentence-end' matched but with nothing left.  Either that
+              ;; means nothing should be removed, or it means it's the
+              ;; "old-style" sentence-end which matches all it can.  Keep only
+              ;; 2 spaces.  We probably don't even need to check
+              ;; `sentence-end-double-space'.
+              ((match-end 1)
+               (min (match-end 0)
+                    (+ (if sentence-end-double-space 2 1)
+                       (save-excursion (goto-char (match-end 0))
+                                       (skip-chars-backward " ")
+                                       (point)))))
+              (t ;; It's not an end of sentence.
+               (+ (match-beginning 0)
+                  ;; Determine number of spaces to leave:
+                  (save-excursion
+                    (skip-chars-backward " ]})\"'")
+                    (cond ((and sentence-end-double-space
+                                (or (memq (preceding-char) '(?. ?? ?!))
+                                    (and sentence-end-without-period
+                                         (= (char-syntax (preceding-char)) 
?w)))) 2)
+                          ((and colon-double-space
+                                (= (preceding-char) ?:))  2)
+                          ((char-equal (preceding-char) ?\n)  0)
+                          (t 1))))))
+             delete-end (match-end 0))
+       (delete-region delete-begin delete-end)
+       ;; Move end position to accommodate for deleted text.
+       (setq end (- end (- delete-end delete-begin)))
+       ))))
 
 (defun fill-common-string-prefix (s1 s2)
   "Return the longest common prefix of strings S1 and S2, or nil if none."
@@ -482,10 +489,12 @@
   (subst-char-in-region from to ?\n ?\s)
   (if (and nosqueeze (not (eq justify 'full)))
       nil
-    (canonically-space-region (or squeeze-after (point)) to)
-    ;; Remove trailing whitespace.
+    ;; Remove trailing whitespace, so canonically-space-region doesn't leave
+    ;; them at the end.  Do this first, since `to' will be invalid after.
     ;; Maybe canonically-space-region should do that.
-    (goto-char to) (delete-char (- (skip-chars-backward " \t"))))
+    (let ((beg (point)))
+      (goto-char to) (delete-char (- (skip-chars-backward " \t")))
+      (canonically-space-region (or squeeze-after beg) (point))))
   (goto-char from))
 
 (defun fill-move-to-break-point (linebeg)

Diff finished.  Thu May 24 14:40:37 2007