bug#46859: 28.0.50; [PATCH]: Add option to truncate long lines in xref.el

[Dmitry Gutov]

On 04.03.2021 11:24, Juri Linkov wrote:
> ;; Without patch
> (benchmark-run 10 (project-find-regexp "expose_frame")) ;; (1.936206149 21 
> 0.27307954999999995)
>
> ;; With patch without the "(unless syntax-needed" guard
> (benchmark-run 10 (project-find-regexp "expose_frame")) ;; (2.195018443 31 
> 0.354854643)

Thanks.

Note that running the benchmark 10 times means that on the last 9 
iterations the lines are already fontified.

The cost of doing this should be apparent with more search hits, though. 
For example:

  (benchmark-run 1 (project-find-regexp "expose"))

> I don't know if extra font-locking is worth worse performance.
> But I took this idea for consistency from occur that uses
> 'font-lock-ensure' in 'occur-engine-line'.

If you're sure you want this behavior, we can make it a user option.