1 files changed, 41 insertions, 16 deletions
diff --git a/runtime/filetype.lua b/runtime/filetype.lua
index fcfc5701f0..9f5b5fd0dc 100644
--- a/runtime/filetype.lua
+++ b/runtime/filetype.lua
@@ -1,26 +1,51 @@
-if vim.g.did_load_filetypes and vim.g.did_load_filetypes ~= 0 then
+-- Skip if legacy filetype is enabled or filetype detection is disabled
+if vim.g.do_legacy_filetype or vim.g.did_load_filetypes then
   return
 end
+vim.g.did_load_filetypes = 1
 
--- For now, make this opt-in with a global variable
-if vim.g.do_filetype_lua ~= 1 then
-  return
-end
+vim.api.nvim_create_augroup('filetypedetect', { clear = false })
 
-vim.cmd [[
-augroup filetypedetect
-au BufRead,BufNewFile * call v:lua.vim.filetype.match(expand('<afile>'))
+vim.api.nvim_create_autocmd({ 'BufRead', 'BufNewFile' }, {
+  group = 'filetypedetect',
+  callback = function(args)
+    local ft, on_detect = vim.filetype.match({ filename = args.match, buf = args.buf })
+    if not ft then
+      -- Generic configuration file used as fallback
+      ft = require('vim.filetype.detect').conf(args.file, args.buf)
+      if ft then
+        vim.api.nvim_cmd({ cmd = 'setf', args = { 'FALLBACK', ft } }, {})
+      end
+    else
+      vim.api.nvim_buf_set_option(args.buf, 'filetype', ft)
+      if on_detect then
+        on_detect(args.buf)
+      end
+    end
+  end,
+})
 
-" These *must* be sourced after the autocommand above is created
-runtime! ftdetect/*.vim
-runtime! ftdetect/*.lua
+-- These *must* be sourced after the autocommand above is created
+if not vim.g.did_load_ftdetect then
+  vim.cmd([[
+  augroup filetypedetect
+  runtime! ftdetect/*.vim
+  runtime! ftdetect/*.lua
+  augroup END
+  ]])
+end
 
-" Set a marker so that the ftdetect scripts are not sourced a second time by filetype.vim
-let g:did_load_ftdetect = 1
+-- Set up the autocmd for user scripts.vim
+vim.api.nvim_create_autocmd({ 'BufRead', 'BufNewFile' }, {
+  group = 'filetypedetect',
+  command = "if !did_filetype() && expand('<amatch>') !~ g:ft_ignore_pat | runtime! scripts.vim | endif",
+})
 
-augroup END
-]]
+vim.api.nvim_create_autocmd('StdinReadPost', {
+  group = 'filetypedetect',
+  command = 'if !did_filetype() | runtime! scripts.vim | endif',
+})
 
 if not vim.g.ft_ignore_pat then
-  vim.g.ft_ignore_pat = "\\.\\(Z\\|gz\\|bz2\\|zip\\|tgz\\)$"
+  vim.g.ft_ignore_pat = '\\.\\(Z\\|gz\\|bz2\\|zip\\|tgz\\)$'
 end