Re: Strange problem with emacs-lisp/copyright.el

[Lele Gaifax <lele@metapensiero.it>]

Some more details on the issue: I added two messages to the workhorse
function, trying to spot where the "point" moves to the wrong location:

(defun copyright-update-year (replace noquery)
  ;; This uses the match-data from copyright-find-copyright/end.
  (goto-char (match-end 1))
  (copyright-find-end)
  ;; LELE
  (message "copyright-find-end says %d" (point))
  (setq copyright-current-year (format-time-string "%Y"))
  (unless (string= (buffer-substring (- (match-end 3) 2) (match-end 3))
                   (substring copyright-current-year -2))
    (if (or noquery
            (save-window-excursion
              (switch-to-buffer (current-buffer))
              ;; Fixes some point-moving oddness (bug#2209).
              (save-excursion
                (y-or-n-p (if replace
                              (concat "Replace copyright year(s) by "
                                      copyright-current-year "? ")
                            (concat "Add " copyright-current-year
                                    " to copyright? "))))))
        (progn
          ;; LELE
          (message "Updating copyright of %s at point %d" (buffer-file-name) (point))
          (if replace
              (replace-match copyright-current-year t t nil 3)
            (let ((size (save-excursion (skip-chars-backward "0-9"))))
              (if (and (eq (% (- (string-to-number copyright-current-year)
                                 (string-to-number (buffer-substring
                                                    (+ (point) size)
                                                    (point))))
                              100)
                           1)
                       (or (eq (char-after (+ (point) size -1)) ?-)
                           (eq (char-after (+ (point) size -2)) ?-)))
                  ;; This is a range so just replace the end part.
                  (delete-char size)
                ;; Insert a comma with the preferred number of spaces.
                (insert
                 (save-excursion
                   (if (re-search-backward "[0-9]\\( *, *\\)[0-9]"
                                           (line-beginning-position) t)
                       (match-string 1)
                     ", ")))
                ;; If people use the '91 '92 '93 scheme, do that as well.
                (if (eq (char-after (+ (point) size -3)) ?')
                    (insert ?')))
              ;; Finally insert the new year.
              (insert (substring copyright-current-year size))))))))

With this in place, I see the following messages when the error happens (I
shortened the filenames for readability):

Saving file /home/lele/[omissis]/grid/Custom.js...
copyright-find-end says 277
Add 2017 to copyright? (y or n) y
Updating copyright of /home/lele/[omissis]/grid/Custom.js at point 5912
Wrote ‘/home/lele/[omissis]/grid/Custom.js’ (11117 characters)
Saving file /home/lele/[omissis]/data/MetaData.js...
copyright-find-end says 288
Add 2017 to copyright? (y or n) y
Updating copyright of /home/lele/[omissis]/data/MetaData.js at point 12155
Wrote ‘/home/lele/[omissis]/data/MetaData.js’ (27857 characters)

As you can see, it seems that the (save-window-excursion ...) that asks
confirmation restores the point where I left it before saving the buffer, not
where (copyright-find-end) moved it.

Does this bring any new information on the issue?

I will try to store the point determined by copyright-find-end in a local
variable and explicitly move there in the inner progn, but I'm obviously
missing... the point :)

Thank you,
ciao, lele.
-- 
nickname: Lele Gaifax | Quando vivrò di quello che ho pensato ieri
real: Emanuele Gaifas | comincerò ad aver paura di chi mi copia.
lele@metapensiero.it  |                 -- Fortunato Depero, 1929.