bug#2209: 23.0.90; copyright-update might not update copyright

[Glenn Morris <rgm@gnu.org>]

Chong Yidong wrote:

> Could you take a look at this bug report for copyright.el?  Thanks.

FWIW, I found this goes away if one sets copyright-query nil, or wraps
the y-or-n-p query in copyright-update-year in a save-excursion.

>> First, emacs -Q and in the initial frame create 2 windows with 2 new
>> files containing:
>>
>> //Copyright (c) 2008 Foo
>> //
>>
>> Now do C-x 5 2 and in the new frame do Tools | Compile RET (it doesn't
>> matter if there's no Makefile etc) and in the *compilation* window in
>> the new frame do C-x 1 M-: (add-hook 'write-file-hooks
>> 'copyright-update) RET.
>>
>> Now in the original frame, add the word "Bar" to the end of the 2nd line
>> in each file, leaving point at the end of the 2nd line, and leaving the
>> files modified.
>>
>> Now in the *compilation* window in the new frame do g ! SPC SPC to
>> recompile/save/update the copyright notices.  
>>
>> I find that one file contains the correct:
>>
>> //Copyright (c) 2008, 2009 Foo
>> //Bar
>>
>> But the other contains the erroneous:
>>
>> //Copyright (c) 2008 Foo
>> //Bar, 2009
>>
>> With point on the comma in the 2nd line.