"company-omnisharp" makes "company-mode" hook slow

[bezirg]

Hello,

When opening other files than .cs, e.g. .el or .ts files, I see that there is a company-omnisharp function called, even if the buffer loaded is not in csharp mode.

This makes the 1st-time-loading of an emacs-lisp file very slow. Trying to profile this with emacs profiler shows:

              - emacs-lisp-mode                                    64  71%
               - run-mode-hooks                                    64  71%
                - apply                                            64  71%
                 - run-hooks                                       64  71%
                  - #<compiled 0x15917b8446e9>                     62  69%
                   - company-mode                                  62  69%
                    - mapc                                         58  65%
                     - company-init-backend                        58  65%
                      + company-omnisharp                          56  62%
                      + company-dabbrev-code                        1   1%
                    + defvar                                        2   2%
                      byte-code                                     1   1%

, which shows that 87% of the time setting up the emacs-lisp-mode was spent on the company-omnisharp function. The impact of this company-omnisharp varies on the file / mode loaded.

Trying to set:

(add-hook 'emacs-lisp-mode-hook (lambda ()
                                  (set (make-local-variable 'company-backends) '(company-capf company-dabbrev-code company-keywords))
                                  (company-mode)
                                  ))

, did not improve loading times and company-omnisharp still ran.

[bezirg]

Could this setup (taking from README) be the culprit?

(eval-after-load
 'company
 '(add-to-list 'company-backends 'company-omnisharp))

[razzmatazz]

Hi @bezirg . Sorry for replying this late. I didn't notice this myself since I am using spacemacs where this is taken care for (major-mode based company-backends list). But I found this on stack overflow:

• https://emacs.stackexchange.com/a/27164/6883

Can you check if making company-backends a local variable for a buffer withmake-local-variable works (in you mode hook) -- and remove global eval-after-load.

I have not tried this solution by myself, but maybe that helps you? And if it does, we can then integrate the fix into README.md