Re: Can project.el or projectile.el help? How about completion?

[Dmitry Gutov]

Hi!

On 31.10.2021 21:48, John Yates wrote:
> I work on a large corporate mono-repo in which numerous
> filenames occur repeatedly.  Further, various directories
> above such duplicates also have duplicated names.

First of all, project-find-files by default uses 'substring' completion.

Which can allow you to type unique parts of the relative file name, 
separated by slashes, press TAB, and then see the name completed.

Completion frameworks like Ivy/Helm/Consult can also affect/augment the 
completion experience.

> Currently I use a self-built emacs tool to index this space:
> * Build a map from a unique filename to a set of
>    repo-relative directory paths to files with that name
> * Compute a disambiguation string for completing reads
>    for unique filenames this string is empty; otherwise:
>    * Repeatedly strip identical leading directories
>    * Repeatedly strip identical trailing directories
>
> I would like to replace this tool with something like
> project.el or projectile.el.  So the first question is does
> either package do anything intelligent when filenames
> are duplicated?  If so, what?

project.el also comes with defcustom called 
project-read-file-name-function. It allows you to write your own wrapper 
which could convert all files names into "disambiguating strings", for 
ease of completion, before the completion prompt is displayed.

> Then, is there any completion package that can present
> the candidates in an order reflecting their distance from
> the current buffer's working directory?  My thought is to
> sort identically named candidates by their repo-relative
> paths.  A focused, incrementally widening presentation
> of candidates would show initially those in or below the
> current working directory.  Each time instructed to widen
> the presentation it would advance up the parent directory
> chain, showing candidates in or below that directory.

Since project-read-file-name-function creates the completion table 
object, you could sort the strings inside it as well, using the 
algorithm of your choice. As long as the table defines 
`display-sort-function', the completion UIs should not re-sort the list 
alphabetically.