bug#31772: 26.1; (thing-at-point 'list) regression

["Andreas Röhler" <andreas.roehler@easy-emacs.de>]

On 07.09.2018 06:42, Leo Liu wrote:
> On 2018-09-06 21:01 +0200, Andreas Röhler wrote:
>> Hi Leo,
>>
>> lets consider the following proposed change of tests:
>>
>> -                         ("(foo\n(a ;(b c d)\ne) bar)" . (a e))
>> +                         ("(foo\n(a ;(b c d)\ne) bar)" . (foo (a e) bar))
>>
>> As the ert-test mentioned  calls (re-search-backward "\\((a\\|^a\\)")
>>
>> point will be behind foo at "(a". I.e. "foo" belongs to outer list,
>> not to list-at-point. The desired result shown by this change looks
>> wrong, "(foo" should not be part of.
>>
>> Maybe I'm missing something.
>> May you provide a standalone example where current behavior breaks
>> your code?
> 
> I carefully considered this case when preparing the patch.
> 
> In the last 10 years (thing-at-point 'list) always returns the enclosing
> list so I opted to keep this for now. It is confusing and I don't like
> it personally.


To check the current correct behavior insert the following lines and try 
the command provided below:

(foo\n(a ;(b c d)
e) bar)

(defun mylist ()
   (interactive)
   (save-excursion
     (goto-char (point-min))
     (search-forward "(a")
     (forward-char -1)
     (thing-at-point 'list t)))


 From "(" it reads the list opened at point.