On 13/04/2024 05:34, Dmitry Gutov wrote:
> Both options are relatively clunky, and the second one might also fail 
> to work when DIRS is non-nil (or would have to fall back to absolute 
> names anyway), so I'm leaning toward the first one. It might also allow 
> certain code to be written supporting both relative and absolute names 
> (e.g. a process call both binds default-directory to root and keeps the 
> file names as-is -- the relative ones would be interpreted as such, the 
> rest just as they are interpreted now).

Here's how that change can look.

The patch should demonstrate both the performance improvements for 
project-find-file and project-find-regexp, and some awkwardness in the 
implementation, chiefly due to backward compatibility.

Guess more tests will be required, at the very least.