bug#6716: 23.2; Setting `find-function-source-path' has no effect.

["Štěpán Němec" <stepnem@gmail.com>]

On Sun, 13 Feb 2022 11:02:33 +0100
Lars Ingebrigtsen wrote:

> Štěpán Němec <stepnem@gmail.com> writes:
>
>> Because `find-library-name' receives as its LIBRARY argument the full
>> path, but doesn't strip the directory part, setting
>> `find-function-source-path' has no effect on symbol finding -- Emacs
>> still tries the path guessed according to load path (which is not
>> correct in case you have the Elisp sources in directory different from
>> the compiled files).
>
> (I'm going through old bug reports that unfortunately weren't resolved
> at the time.)
>
> `find-function-source-path' is now obsolete (`find-library-source-path'
> is used instead), but there wasn't a case to reproduce the problem here.
> Are there still problems in this area in recent Emacs versions?  If so,
> do you have a recipe to reproduce the problem?

It was the same issue as later reported in bug#50508 (which does include
a simple reproducer), and from a quick look at the current source code
it seems that the description you quote above still applies, too.

My specific use case was jumping (via e.g. `find-function') to source
files (typically a VCS repository checkout) when running an Emacs
without the sources installed along the compiled files.

Looking at bug#50508, it seems you have decided to not try to fix this,
and instead adjust the docs and rename/obsolete the option, so I guess
you'll want to close this one, too.

BTW, while grepping now I noticed `package--reload-previously-loaded'
still trying to use `find-function-source-path'; I don't know if or how
it should be updated.

-- 
Štěpán