eRuby files incorrectly indentified as Mason

[goronfreeman]

From v4.9.9+, all eRuby files are now being identified as Mason files. Disabling polyglot and installing the latest version of the vim-ruby plugin does not exhibit this behavior.

To Reproduce:

1. Install polyglot v4.9.9+
2. Open any file with the extension .erb

[sheerun]

there's no mason in vim-polyglot

[sheerun]

if you mean meson, then vim-polyglot doesn't associate it with .erb, here's the code:

if !has_key(s:disabled_packages, 'meson')
  au BufNewFile,BufRead meson.build setf meson
  au BufNewFile,BufRead meson_options.txt setf meson
  au BufNewFile,BufRead *.wrap setf dosini
endif

[goronfreeman]

I actually did mean mason, not meson. Here is the result of running :set filetype? without polyglot:

Here is the same file after enabling polyglot:

This issue appeared in 4.9.9, as rolling back to 4.9.8 fixes the issue.

[goronfreeman]

I did also notice that it's not all files this happens with. The screenshot above is for a file named index.html.erb. Another file with the name show.html.erb seemed to work as expected.

[sheerun]

what happens if you disable all other plugins than polyglot?

[goronfreeman]

That's what I did for the screenshots above. Here is my init.vim I'm using to try to help debug this:

call plug#begin('~/.config/nvim/plugged')
Plug 'sheerun/vim-polyglot'
call plug#end()

This is using the latest stable neovim release v0.4.4 and vim plug.

After digging into this a little more, I think I found the issue. It seems that if a file with the extension .html.erb does not contain any HTML and only ERB, this is when this happens. For instance, here is one of the files that is identified incorrectly:

<%= render partial: 'shared/games', locals: { games: @games, ajax: false, pagy: @pagy, show_links: true, view: :list } %>

Here is one that is identified correctly:

<div class="container">
  <div class="card">
    <div class="card-image has-background-grey-light video-responsive">
      <iframe width="560"
              height="315"
              src="<%= @game.trailer %>"
              title="<%= @game.title %> Trailer"
              frameborder="0"
              allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture"
              allowfullscreen></iframe>
    </div>

    <div class="card-content">
      <div class="media">
        <div class="media-left">
          <figure class="image is-96x96">
            <%= image_tag @game.front_box_art, alt: @game.title %>
          </figure>
        </div>

        <%= render partial: 'price_info', locals: { game: @game } %>
      </div>

      <div class="content">
        <% if @game.on_sale? %>
          <%= render partial: 'countdown', locals: { game: @game } %>
        <% end %>

        <div class="button-container">
          <%= render partial: 'shared/button', locals: { game: @game } %>
          <%= link_to 'Buy Digital', @game.purchase_link, target: '_blank', class: 'button is-link' %>
          <%= link_to 'Game Info', @game.url, target: '_blank', class: 'button is-link' %>
        </div>
        <br>

        <%= render partial: 'footer', locals: { game: @game } %>
      </div>
    </div>
  </div>
</div>

I confirmed this opening other .html.erb templates that only render partials, and they all exhibit the same behavior. I also tested this same thing installing the vim-ruby plugin directly using vim-plug, and it works fine with every file. This seems strange, since as far as I could tell, that's what polyglot uses for Ruby.

Let me know if I can provide any more information to help with this issue.

[sheerun]

Thank you it was very helpful. It seems vim native ftdetect scripts are hard-setting filetype: https://github.com/vim/vim/blob/master/runtime/scripts.vim#L210-L211 (they use set ft= instead of setf). Because vim-polyglot uses setf it doesn't override what set ft= set. vim-ruby doesn't have this issue because it uses let &filetype = a:filetype which is essentially the same as set ft=. While it seems like a bug on vim side, I need to fix it on vim-polyglot side because we can't control what version of vim user has installed.

The ultimate solution is to disable all filetypedetection on vim side and make vim use only vim-polyglot defined ftdetect, but I cannot do it until I migrate all filetypes from vim. For now a hack will suffice, similar to what vim-ruby does.