Re: Moving point around empty overlays with 'after-text

[Platon Pronko <platon7pronko@gmail.com>]

On 2023-04-08 18:06, Eli Zaretskii wrote:
>> Date: Fri, 07 Apr 2023 22:46:19 -0700
>> From: Ash <ext0l@catgirl.ai>
>>
>> https://github.com/emacs-lsp/lsp-mode/issues/3263 is a bug in lsp-mode (emacs's
>> own eglot has the same bug as far as I can tell) that appears to boil down to
>> the behavior of emacs overlays and after-string. That is, if your buffer looks
>> like
>>
>> let my_value{: Vec<i32>} = vec![0, 1, 2];
>>
>> (where the curly braces indicate the after-string property of an
>> overlay), you need to put your cursor *after* the overlay to
>> insert text at the end of the variable name, which comes *before*
>> it, and it's impossible to put your cursor immediately between
>> the overlay and the preceding text. I assume the behavior the
>> user desires is that you can put your cursor either immediately
>> before or immediately after the overlay and insert text, and that
>> pressing the left/right arrow would move you over the overlay but
>> leave the actual position of point unchahnged.
>>
>> My suspicion is that this isn't fixable just by setting the right text/overlay
>> properties, since both the cursor locations immediately before and after the
>> overlay actually correspond to the same location in the underlying string. But
>> I'm not good at text property arcana. Any advice?
> 
> Did you try to use on the overlay string the 'cursor' text property
> whose value is zero?
> 

As I understand that it won't help, because they have to use zero-width overlays here,
and the behavior of 'cursor property in such cases is not to be relied upon (as you previously
suggested in https://debbugs.gnu.org/cgi/bugreport.cgi?bug=62540).

-- 
Best regards,
Platon Pronko
PGP 2A62D77A7A2CB94E