Re: [emms-help] emms-player-mpv ipc-error: connection-error

[Mike Kazantsev]

On Sun, 01 Jul 2018 22:31:54 +0300
Konstantin Reich <address@hidden> wrote:

> Mike,
> 
> Yeah i cannot figure out what it is going on.
> 
> > You don't have it disabled or overidden manually somewhere, by chance?  
> no
> 
> (>= emacs-major-version 26)  
> gives
> t

Guess one other option is that something straight-up does:

  (let ((emacs-major-version 25)) ... (require 'emms-player-mpv) ...)

...somewhere, maybe as a bad workaround for whatever weird quirk.

Sorry that it's already a lot of work for issue that you
probably don't particulary care about, but maybe you can edit that elpa
file at /home/reich/.emacs.d/elpa/emms-20180630.945/emms-player-mpv.el
and next to (defvar emms-player-mpv-ipc-conn-emacs-26-workaround ...)
line (e.g. right after it), put something like this:

  (message "------ emms-mpv: emacs-major-version on load: %s" 
emacs-major-version)
  (message "------ emms-mpv: workaround value init: %s" 
emms-player-mpv-ipc-conn-emacs-26-workaround)

And then restart emacs, make it load/init emms as you'd usually do, and
look into *Messages* afterwards for these two lines.

First one should show if maybe emacs-major-version is indeed overidden,
while second one might reveal whether variable is initialized to t and
then reset to nil or if latter happens on initialization there.


And if it's the latter case of something changing variable indeed
(probably is, given that it's defined in the right place and
emacs-major-version hack seems very unlikely), then edit that file
again and instead of these two "message" lines put this one there:

  (debug-watch 'emms-player-mpv-ipc-conn-emacs-26-workaround)

This should land you in an emacs debugger with a backtrace should
anything ever try to change that variable (nothing in emms code should
afaik), so likely will signal such error upon next restart and emms init.

Found out about this new feature of emacs-26.1 myself googling for how
to trace variable changes just now.


Again, thanks and apologies for all the debugging work you've done on
this issue already.

Got comment on underlying emacs issue, confirming that it might be
accidental bug during refactoring, so might hopefully be fixed without
need for such workarounds in the next emacs version releases.
https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=e09c0972c350e9411683b509414fc598cbf387d3


-- 
Mike Kazantsev // fraggod.net