Issues setting up company-reftex

[thomasflynn918]

Hi, This package seems awesome and I'd love to see it working but am having difficulty.

It seems the package is installed properly, but the appropriate functions are not called when \ref{ or \eqref{ are typed.

If I type M-x c-r-l at \ref{ I do see an autocomplete menu.

Any idea why the autocomplete is not 'auto' in my case?

To try and isolate the issue, I made a virtual machine instance and installed stock Debian 10.8 and got their default emacs (version is 26.1) Here is my .emacs

(require 'package)
(require 'reftex)

(setq gnutls-algorithm-priority "NORMAL:-VERS-TLS1.3")
(add-to-list 'package-archives
         '("melpa-stable" . "https://melpa.org/packages/") t)
(package-initialize)

(add-hook 'Latex-mode-hook 'turn-on-reftex)
(add-hook 'latex-mode-hook 'turn-on-reftex)

(custom-set-variables
 '(package-selected-packages (quote (company-reftex company))))
(custom-set-faces)

(use-package company
  :ensure t
  :custom
  (company-idle-delay 0.0)
  :config (global-company-mode 1))

(eval-after-load "company"
  '(add-to-list
    'company-backends
    'company-reftex-labels
    'company-reftex-citations))

If someone could provide some tips or a minimal example of a working .emacs that would be very helpful. Thank you!

[atreyasha]

@thomasflynn918 I can try to help with this.

If I type M-x c-r-l at \ref{ I do see an autocomplete menu.

That would mean that company-reftex works in general, so that seems good.

Any idea why the autocomplete is not 'auto' in my case?

My hunch is it could be due to company-minimum-prefix-length. If it is set to the default value of 2 (I think), then you might need to type at least 2 characters after \ref{ or \eqref{ to have it automatically complete. Setting this value to 0 should theoretically work but could be annoying, but anw it seems this was already discussed here: https://emacs.stackexchange.com/questions/12441/is-it-possible-to-start-company-completion-without-a-prefix

[Sparsa]

Hi, I have facing the same issue with my implementation even with the 2 letter, I guess company-complete is not triggering company-reftex-label ? I have assigned a keybinding to company-complete.

[TheBB]

People who experience this, please confirm that you've set the minimum prefix length to 0 as @atreyasha suggested.

[atreyasha]

I have facing the same issue with my implementation even with the 2 letter, I guess company-complete is not triggering company-reftex-label ? I have assigned a keybinding to company-complete.

@Sparsa do you see citation/label autocompletions when you manually execute company-complete at the relevant point? If it does not, this would be a separate issue compared to @thomasflynn918 since they still can see an autocompletion menu, just that it is not automatically shown while typing.

In any case, I tested on my local setup and company-reftex works just fine for me. I would recommend testing the \cite{ environment first rather than the \ref{ environment since the latter might erroneously show no atuocompletion due to reasons cited in #11.

[Sparsa]

People who experience this, please confirm that you've set the minimum prefix length to 0 as @atreyasha suggested.

I am fine with typing two characters, but for my case, even with two letters (or 4 or 6), it does not show up until I manually call Mx c-r-l.

Also, can anyone share the code about how you are adding this backend to the company-backend list?

(set (make-local-variable 'company-backends) '(company-math-symbols-latex
        company-latex-commands company-reftex-labels
        company-reftex-citations))

I am using something like this in LaTeX-mode-hook. I turned on company-mode globally, before that in my init.el.

[atreyasha]

Unfortunately I use spacemacs so I can't provide just a few lines responsible in my config. However, my company-diag output shows:

company-backends: ((:separate company-reftex-labels company-reftex-citations)
 (:separate company-auctex-symbols company-auctex-environments company-capf company-auctex-macros)
 (company-semantic company-dabbrev-code company-gtags company-etags company-keywords)
 company-files company-dabbrev)

In regards to specific elisp code, maybe something like this:

(setq-local company-backends
              (append '((:separate company-reftex-labels company-reftex-citations))
                      company-backends))

BTW is the issue similar to the following?

https://emacs.stackexchange.com/questions/61065/cant-get-company-reftex-labels-to-work-properly

[Sparsa]

Yes, actually I think the problem was in the configuration itself, I was thinking of this company-backend as a list, but it can have a hierarchy, just like you have posted, I just made a group and now it works perfectly fine. Thank you for helping me. I am quoting the documentation from M-x customize-variable RET company-reftex-citations

   ================

   An element of ‘company-backends’ can also be a list of backends.  The
   completions from backends in such groups are merged, but only from those
   backends which return the same ‘prefix’.

   If a backend command takes a candidate as an argument (e.g. ‘meta’), the
   call is dispatched to the backend the candidate came from.  In other
   cases (except for ‘duplicates’ and ‘sorted’), the first non-nil value among
   all the backends is returned.

   The group can also contain keywords.  Currently, ‘:with’ and ‘:separate’
   keywords are defined.  If the group contains keyword ‘:with’, the backends
   listed after this keyword are ignored for the purpose of the ‘prefix’
   command.  If the group contains keyword ‘:separate’, the candidates that
   come from different backends are sorted separately in the combined list.```

[atreyasha]

Awesome, glad to hear it worked. Yes company-backends is IMO a complicated object and it requires some tweaking to get it to cooperate with other backends.

[YueRen]

Sorry, emacs beginner here, just wanted to make sure that my solution is acceptable. I had the very same problem as @thomasflynn918 originally reported and @Sparsa used to have. Upon @atreyasha suggestion, I tried replacing

     (setq company-backends
        '((
           company-capf
           ;; company-tabnine
           company-bibtex
           company-math-symbols-latex
           company-latex-commands
           company-math-symbols-unicode
           company-reftex-labels
           company-reftex-citations
           company-yasnippet
           company-files
           company-ispell
           company-dabbrev
           )))

in https://emacs.stackexchange.com/a/61081/30026 with

   (setq-local company-backends
               (append '((:separate company-reftex-labels company-reftex-citations))
                       company-backends))

This worked great at first, but adding more backends to the list like

   (setq-local company-backends
               (append '((:separate company-math-symbols-latex company-latex-commands company-math-symbols-unicode company-reftex-labels company-reftex-citations))
                       company-backends))

made the old problem resurface. But appending backends as follows seems to work:

  (setq-local company-backends
               (append '((:separate company-math-symbols-latex company-math-symbols-unicode company-latex-commands))
               company-backends))
  (setq-local company-backends
               (append '((:separate company-reftex-labels company-reftex-citations))
                       company-backends)))

Is this the way to go or is there a cleaner solution?

[atreyasha]

Hmm I am not sure why this happens, but good to know you found a solution that at least works. To diagnose the problem better, could you provide the following outputs after opening a tex file or being in the latex-mode major mode:

1. Output of M-x company-diag with this in your configuration:

(setq-local company-backends
            (append '((:separate company-math-symbols-latex
                                 company-latex-commands
                                 company-math-symbols-unicode
                                 company-reftex-labels
                                 company-reftex-citations))
                    company-backends))

2. Output of M-x company-diag with this in your configuration:

(setq-local company-backends
            (append '((:separate company-math-symbols-latex
                                 company-math-symbols-unicode
                                 company-latex-commands))
                    company-backends))

(setq-local company-backends
            (append '((:separate company-reftex-labels
                                 company-reftex-citations))
                    company-backends)))

3. Could you check if using this in your emacs configuration works? I just reordered the backends.

(setq-local company-backends
            (append '((:separate company-reftex-labels
                                 company-reftex-citations
                                 company-math-symbols-latex
                                 company-latex-commands
                                 company-math-symbols-unicode
                                 ))
                    company-backends))

4. Are you using base emacs or a distribution?

Answers to these might help diagnose the situation better. My hunch is that there is some conflict between the backends, which results in problems when they are all chunked together. Perhaps this is why appending the backends with two separate commands helps.

[YueRen]

Hmm I am not sure why this happens, but good to know you found a solution that at least works. To diagnose the problem better, could you provide the following outputs after opening a tex file or being in the latex-mode major mode:

Gladly! Hope you don't mind me using pastepin, the output is quite long and I couldn't find a collapsible code-block feature.

1. Output of `M-x company-diag` with this in your configuration:

(setq-local company-backends
            (append '((:separate company-math-symbols-latex
                                 company-latex-commands
                                 company-math-symbols-unicode
                                 company-reftex-labels
                                 company-reftex-citations))
                    company-backends))

https://pastebin.com/aCemrhgx (problem persists)

2. Output of `M-x company-diag` with this in your configuration:

(setq-local company-backends
            (append '((:separate company-math-symbols-latex
                                 company-math-symbols-unicode
                                 company-latex-commands))
                    company-backends))

(setq-local company-backends
            (append '((:separate company-reftex-labels
                                 company-reftex-citations))
                    company-backends)))

https://pastebin.com/DTEvAuAp (problem fixed)

3. Could you check if using this in your `emacs` configuration works? I just reordered the backends.

(setq-local company-backends
            (append '((:separate company-reftex-labels
                                 company-reftex-citations
                                 company-math-symbols-latex
                                 company-latex-commands
                                 company-math-symbols-unicode
                                 ))
                    company-backends))

No, problem still exists.

4. Are you using base `emacs` or a distribution?

I am using GNU Emacs 26.3 in Ubuntu 20.04.2, which I think I installed using apt. I am running Emacs in the terminal via "/usr/bin/emacs -nw".

Answers to these might help diagnose the situation better. My hunch is that there is some conflict between the backends, which results in problems when they are all chunked together. Perhaps this is why appending the backends with two separate commands helps.

Good luck! I wish I could help but Emacs is not my forte. :-/

[atreyasha]

My bad, I should have mentioned I just needed everything except the completions; which is what makes the output so long.

But in any case, these outputs show that everything in the configuration is being reflected correctly in the company backends; which is a good first check. So indeed the problem is with the grouping of the backends. tl;dr I think your workaround makes sense and I would stick with it as long as it solves your problem.

Sorry I can't share anything useful from my configuration because I use an emacs distribution. But if you notice the company-backends in my setup, it also uses two different groups with the :separate flag:

company-backends: ((:separate company-reftex-labels company-reftex-citations)
 (:separate company-auctex-symbols company-auctex-environments company-capf company-auctex-macros)
 (company-semantic company-dabbrev-code company-gtags company-etags company-keywords)
 company-files company-dabbrev)

If you still feel like investigating further, I could recommend the following:

1. Setup your emacs with a configuration that reproduces the problem
2. Open a tex file which should theoretically have citation or label candidates, or which showed these candidates when you used a configuration that fixes the problem
3. Type the relevant keyword such as \cite{ or \ref{ and place your cursor one character after these keywords; eg. \cite{[cursor-here]
4. Execute M-x company-complete
5. Immediately after, execute M-x company-diag

The important output to look at would be on and after the Used backend bit. This would tell you which backend was used in this step, what prefix it parsed and what completions it received.