[O] Re: org-src-fontify-natively makes things very, very slow

[Sébastien Vauban]

Hi Matt,

Matt Lundin wrote:
> Sébastien Vauban writes:
>>>> Maybe this is (partly?) due to the overlay I added:
>>>>
>>>> #+begin_src emacs-lisp
>>>>                 (overlay-put (make-overlay beg1 block-end)
>>>>                              'face 'org-block-background))
>>>> #+end_src
>
> I believe there is a bug here. I'm not sure if it is related to the
> performance issues, but when org-src-fontify-natively is t, new overlays
> keep getting added to the source block with each keypress in the source
> block.
>
> For instance, just typing this line of perl...
>
> #+begin_src perl
>   my @apples = ("golden delicious", "braeburn");
> #+end_src
>
> ...resulted in 54 identical overlays being added to the buffer.
>
> ,----[ M-x describe-text-properties
> | There are 54 overlays here:
> |  From 39 to 88
> |   face                 org-block-background
> |  From 39 to 88
> |   face                 org-block-background
> |  From 39 to 88
> |   face                 org-block-background
> |  From 39 to 88
> |   face                 org-block-background
> | ....[and so on]
> `----

I believe as well there is a problem!

> The number keeps growing with more typing, since make-overlay is called
> without a test to see if an overlay already exists.

Thanks (a lot) for your very enlightening analysis. I will try to get this
fixed in a couple of days.

Best regards,
  Seb

-- 
Sébastien Vauban