(c-mask-comment): A better way to ensure point doesn't move around

unexpectedly.  Also handles the paragraph fill case.

1 files changed, 25 insertions, 23 deletions

diff --git a/lisp/progmodes/cc-cmds.el b/lisp/progmodes/cc-cmds.el
index 96b72eb1754..b23b7657996 100644
--- a/lisp/progmodes/cc-cmds.el
+++ b/lisp/progmodes/cc-cmds.el
@@ -2761,10 +2761,14 @@ command to conveniently insert and align the necessary backslashes."
                   '("" . 0))))))
     ))
 
-(defun c-mask-comment (fill-mode apply-outside-literal fun &rest args)
+(defun c-mask-comment (fill-paragraph apply-outside-literal fun &rest args)
   ;; Calls FUN with ARGS ar arguments.  If point is inside a comment,
   ;; the comment starter and ender are masked and the buffer is
   ;; narrowed to make it look like a normal paragraph during the call.
+  ;;
+  ;; FILL-PARAGRAPH is non-nil if called for paragraph filling.  The
+  ;; position of point is then less significant when doing masking and
+  ;; narrowing.
   (let (fill
         ;; beg and end limits the region to narrow.  end is a marker.
         beg end
@@ -2790,7 +2794,7 @@ command to conveniently insert and align the necessary backslashes."
       ;; Widen to catch comment limits correctly.
       (widen)
       (unless c-lit-limits
-        (setq c-lit-limits (c-literal-limits nil fill-mode)))
+        (setq c-lit-limits (c-literal-limits nil fill-paragraph)))
       (setq c-lit-limits (c-collect-line-comments c-lit-limits))
       (unless c-lit-type
         (setq c-lit-type (c-literal-type c-lit-limits))))
@@ -2840,8 +2844,8 @@ command to conveniently insert and align the necessary backslashes."
                                                  "\\)\\*/"))
                              (eq (cdr c-lit-limits) (match-end 0))
                              ;; Leave the comment ender on its own line.
-                             (set-marker end (max (point) here))))
-                (when fill-mode
+                             (set-marker end (point))))
+                (when fill-paragraph
                   ;; The comment ender should hang.  Replace all cruft
                   ;; between it and the last word with one or two 'x'
                   ;; and include it in the region.  We'll change them
@@ -2900,13 +2904,11 @@ command to conveniently insert and align the necessary backslashes."
               ;; The region includes the comment starter.
               (save-excursion
                 (goto-char (car c-lit-limits))
-                (when (and (looking-at comment-start-skip)
-                           (> here (match-end 0)))
-                  (if (eq (match-end 0) (c-point 'eol))
-                      ;; Begin with the next line.
-                      (setq beg (c-point 'bonl))
-                    ;; Fake the fill prefix in the first line.
-                    (setq tmp-pre t))))))
+                (if (looking-at (concat "\\(" comment-start-skip "\\)$"))
+                    ;; Begin with the next line.
+                    (setq beg (c-point 'bonl))
+                  ;; Fake the fill prefix in the first line.
+                  (setq tmp-pre t)))))
            ((eq c-lit-type 'string)     ; String.
             (save-excursion
               (when (>= end (cdr c-lit-limits))
@@ -2984,24 +2986,24 @@ Warning: Regexp from `c-comment-prefix-regexp' doesn't match the comment prefix
                                               ""))))
                            (car (or fill (c-guess-fill-prefix
                                           c-lit-limits c-lit-type))))))
-                    ;; Don't remember why I added this, but it doesn't
-                    ;; work correctly since `here' can point anywhere
-                    ;; after the deletes and inserts above.
-                    ;(point-rel (cond ((< here beg) (- here beg))
-                    ;                  ((> here end) (- here end))))
-                    )
+                    ;; Save the relative position of point if it's
+                    ;; outside the region we're going to narrow.  Want
+                    ;; to restore it in that case, but otherwise it
+                    ;; should be moved according to the called
+                    ;; function.
+                    (point-rel (cond ((< (point) beg) (- (point) beg))
+                                     ((> (point) end) (- (point) end)))))
                 ;; Preparations finally done! Now we can call the
                 ;; actual function.
                 (prog1
                     (save-restriction
                       (narrow-to-region beg end)
                       (apply fun args))
-                  ;(if point-rel
-                  ;    ;; Restore point if it was outside the region.
-                  ;    (if (< point-rel 0)
-                  ;       (goto-char (+ beg point-rel))
-                  ;     (goto-char (+ end point-rel))))
-                  ))
+                  (if point-rel
+                      ;; Restore point if it was outside the region.
+                      (if (< point-rel 0)
+                          (goto-char (+ beg point-rel))
+                        (goto-char (+ end point-rel))))))
             (when apply-outside-literal
               (apply fun args))))
       (when (consp tmp-pre)