Re: Cleaning up and structuring user-emacs-directory

[David De La Harpe Golden]

On 19/08/2020 09:28, tomas@tuxteam.de wrote:

> I've now read the freedesktop thing. If you ask me: please make that
> optional.

indeed, existing emacs fd.o support in various contexts is generally 
optional.

> I have none of those $XDG_* env vars set, and I have nothing
> of relevance in .local.

They're overrides not mandatory, the normal circumstance for an app that 
follows the spec is falling back to the standard paths.  When emacs uses 
them, which it may already do in various circumstances, you can see it 
does that:

https://git.savannah.gnu.org/cgit/emacs.git/tree/lisp/xdg.el#n52

At startup, emacs apparently already uses  ~/.config/emacs/ if present 
and .emacs and ~/.emacs.d aren't:

https://git.savannah.gnu.org/cgit/emacs.git/tree/lisp/startup.el#n494

However, at time of writing a user using the existing emacs xdg 
~/.config/emacs/ dir  support will AFAICS actually find various arguably 
"data" and "cache" files also plonked into the "config" directory 
~/.config/emacs/ dir by emacs, as it's basically treated as an 
alternatively spelled ~/.emacs.d/

That may be consided at least vaguely suspect under the xdg spec 
conventions, user config, cache and data files are supposed to have 
those split locations.  To concretize, testing with emacs 27.1 
(personally I actually still use ~/.emacs and ~/.emacs.d/ normally!):


# keep for restoration!

$ mkdir -p .config/emacs/
$ cp .emacs .config/emacs/init.el
$ mv .emacs .emacs.off
$ mv .emacs.d .emacs.d.off


Run emacs

$ emacs

# intra-emacs do something arguably "cache" and "data" like getting the
# latest elpa package list and installing a package

M-x list-packages
<install something, trie for argument's sake>
C-x C-c


#  let's look inside:

ls ~/.config/emacs/


$ ls -1 ~/.config/emacs/
auto-save-list
elpa
init.el

$ ls -1 ~/.config/emacs/elpa/
archives
gnupg
heap-0.5
heap-0.5.signed
queue-0.2
queue-0.2.signed
tNFA-0.1.1
tNFA-0.1.1.signed
trie-0.4
trie-0.4.signed


# -> user ends up with emacs init.el in config (fine), but also
# elpa package lists stored in xdg config subdir not cache
# elpa packages installed in xdg config subdir not data

This contrasts to e.g. python's "pip install --user", as that will 
install python packages  ~/.local/lib/python3 etc. as "data", and keep 
its various transient metadata things in ~/.cache/pip/ as "cache"


















> Cheers
>   - t