doc: Add nvim-compe to the autocompletion section

[savq]

Following this reddit thread, this PR adds some information on how to use VimTeX with nvim-compe.

I didn't find info on whether compe can use regex patterns for filetypes 😕 but I followed u/mybumsonfire advice on adding the filetype explicitly.

I added a code sample in Lua, though another one in Vimscript can also be added.

I'm glad VimTeX is so well documented 👍

[jdhao]

I am writing just to confirm that @savq has provided the correct config (which the original reddit post is not). The value for the key filetypes should be a list, not string. My working config for nvim-come (in lua):

require'compe'.setup {
  enabled = true;
  autocomplete = true;
  debug = false;
  min_length = 1;
  preselect = 'always';
  throttle_time = 80;
  source_timeout = 200;
  incomplete_delay = 400;
  max_abbr_width = 100;
  max_kind_width = 100;
  max_menu_width = 100;
  documentation = true;

  source = {
    omni = {filetypes = {'tex'}};
    path = true;
    buffer = true;
    spell = {filetypes = {'markdown', 'tex'}};
    emoji = true;
    nvim_lsp = true;
    nvim_lua = true;
    ultisnips = true;
    calc = false;
    vsnip = false;
  };
}

Related: hrsh7th/nvim-compe#166 and hrsh7th/nvim-compe#170 (comment)

[lervag]

Following this reddit thread, this PR adds some information on how to use VimTeX with nvim-compe.

Thank you!

I'm glad VimTeX is so well documented +1

Yes, I think it's important to aim for good documentation, especially considering the size of the plugin. And help from people like you is therefore very useful!

I am writing just to confirm that @savq has provided the correct config (which the original reddit post is not).

Thanks! Also thanks for the references to relevant issues!

---

One open question remains: Is there something in nvim-compe that is equivalent to the input_patterns variable in deoplete/neocomplete, or the complete_pattern in ncm2?

[savq]

One open question remains: Is there something in nvim-compe that is equivalent to the input_patterns variable in deoplete/neocomplete, or the complete_pattern in ncm2?

@lervag, compe seems to be able to use regex patterns for the buffer source, but not for omni-completion. The default pattern matches alphanumeric words, including kebab-case: \h\w*\%(-\w*\)*. The docs mention it's an experimental feature.

[lervag]

Ok, thanks. If something like that should be implemented, then feel free to notify me and/or suggest an update to the configuration suggestions in the docs.