feat: refactor treesitter filetype detection

Author: zdm

autoload/vsnip/source.vim

@@ -23,12 +23,25 @@ endfunction
 "
 function! vsnip#source#filetypes( bufnr ) abort
   if has( "nvim" )
-    let l:filetype = v:lua.require'vsnip.treesitter'.get_ft_at_cursor( a:bufnr )
+    let l:filetypes = v:lua.require'vsnip.treesitter'.get_ft_at_cursor( a:bufnr )
+
+    if l:filetypes.filetype == ""
+      return [ "global" ]
+    else
+      return get(
+        \ g:vsnip_filetypes, l:filetypes.injected_filetype,
+        \ get( g:vsnip_filetypes, l:filetypes.filetype,
+        \ [ l:filetypes.filetype ]
+        \ ) )
+        \ + [ "global" ]
+    endif
   else
     let l:filetype = getbufvar( a:bufnr, "&filetype", "" )
-  endif
 
-  return split( l:filetype, '\.' ) + get( g:vsnip_filetypes, l:filetype, [] ) + [ "global" ]
+    " FIXME: split( l:filetype, '\.' ) - does it has any sense, can buffer filetype contain "." character?
+    " return split( l:filetype, '\.' ) + get( g:vsnip_filetypes, l:filetype, [] ) + [ "global" ]
+    return [ l:filetype ] + get( g:vsnip_filetypes, l:filetype, [] ) + [ "global" ]
+  endif
 endfunction
 
 "

lua/vsnip/treesitter.lua

@@ -23,6 +23,11 @@ function M.is_available ()
 end
 
 function M.get_ft_at_cursor ( bufnr )
+  local filetypes = {
+    filetype = "",
+    injected_filetype = "",
+  }
+
   if M.is_available() then
     local cur_node = ts_utils.get_node_at_cursor( vim.fn.bufwinid( bufnr ) )
 
@@ -34,23 +39,27 @@ function M.get_ft_at_cursor ( bufnr )
       local filetype = get_parser_filetype( language_at_cursor )
 
       if filetype ~= "" then
+        filetypes.filetype = filetype
+
         local parent_language_tree = language_tree_at_cursor:parent()
 
         if parent_language_tree then
           local parent_language = parent_language_tree:lang()
           local parent_filetype = get_parser_filetype( parent_language )
 
           if parent_filetype ~= "" then
-            filetype = filetype .. "." .. parent_filetype .. "/" .. filetype
+            filetypes.injected_filetype = parent_filetype .. "/" .. filetype
           end
         end
 
-        return filetype
+        return filetypes
       end
     end
   end
 
-  return vim.bo[ bufnr ].filetype or ""
+  filetypes.filetype = vim.bo[ bufnr ].filetype or ""
+
+  return filetypes
 end
 
 return M