Re: No next track in playlist

[Mike Kazantsev]

On Wed, 06 Jan 2021 23:21:10 +0100
Arthur Miller <arthur.miller@live.com> wrote:

> Mike Kazantsev <mk.fraggod@gmail.com> writes:
> 
> > Try setting (setq emms-player-mpv-debug t) and checking what it says in
> > the Messages buffer, maybe send it here, if it's unclear what's the
> > problem there.  

> I set emms-player-mpv-debug but I see nothing different in messages.
> Does debug info goes elsewhere?
...
> It plays fine; so I guess it is something to my emms mpv configuration.

No, should be checked in emms-player-mpv-debug-msg calls, so enabling it
anytime and doing anything mpv-related should produce some output there.

As it does not, guess player backend from emms-player-mpv never runs,
so guess it should be an issue elsewhere.


> > You can customize binary/path and other startup parameters in
> > emms-player-mpv customization group interactively, or via
> > custom-set-variables for emms-player-mpv-command-name,
> > emms-player-mpv-parameters, emms-player-mpv-environment, etc
> > (all should be listed under that group, and at the top of .el file too).  
> 
> Ok, I have simplified the setup, removed all custom paths and
> unnecessary stuff; now there is just "mpv" part to it.
> 
> Above start-process call plays fine, yet when I run setup
> below I still get no-next-track message.
> 
...
>               (setq-default emms-player-list '(emms-player-mpv)
>                             emms-player-mpv-ipc-method t

emms-player-mpv-ipc-method should not be t, it is defined as:

  (defcustom emms-player-mpv-ipc-method nil
    "Switch for which IPC method to use with mpv.
  Possible symbols: detect, ipc-server, unix-socket, file.
  Defaults to nil value, which will cause `emms-player-mpv-ipc-detect'
  to pick one based on mpv --version output.
  Using JSON-IPC variants (ipc-server and unix-socket) enables
  support for various feedback and metadata options from mpv."
    :type '(choice
      (const :tag "Auto-detect from mpv --version" nil)
      (const :tag "Use --input-ipc-server JSON IPC (v0.17.0 2016-04-11)" 
ipc-server)
      (const :tag "Use --input-unix-socket JSON IPC (v0.7.0 2014-10-16)" 
unix-socket)
      (const :tag "Use --input-file FIFO (any mpv version)" file))
    :group 'emms-player-mpv)

And that's kinda why you might want to use custom-set-variables for
anything defcustom - pretty sure it should give you an error for such
invalid value.

And furthermore, using setq for something like
emms-player-mpv-update-metadata will not run the :set hooks there,
and won't do anything, so again, shouldn't use setq for these.


> Debug flag does not give me much: this is what I get from a freshly
> started Emacs in *Messages* after running emms on a directory:
...
> It shouldn't matter that I have my configuration in eval-after-load (or
> rather with-eval-after-load macro), right?

Yeah, don't think it should matter, and given that debug output is
missing, I'd suspect that for some reason backend is just not used -
maybe some issue with playlist and tracks there?

Not sure what it might be, and I'd probably open emms-player-mpv.el
at this point and try adding e.g. (error "is this working?") as first
line in emms-player-mpv-start function, eval it like that, make sure
it's not just an issue with debug logging, and maybe go check emms.el
in a similar fashion from there.

There probably are more efficient ways to debug code than such
printf-lines, and that's just my go-to with an arbitrary code.


-- 
Mike Kazantsev // fraggod.net