refactor(runtime): port remaining patterns from filetype.vim to filetype.lua (#18814)

2 files changed, 360 insertions, 72 deletions

diff --git a/runtime/lua/vim/filetype.lua b/runtime/lua/vim/filetype.lua
index f5c29639c6..c091e2f35c 100644
--- a/runtime/lua/vim/filetype.lua
+++ b/runtime/lua/vim/filetype.lua
@@ -3,21 +3,22 @@ local api = vim.api
 local M = {}
 
 ---@private
-local function starsetf(ft)
+local function starsetf(ft, opts)
   return {
-    function(path)
+    function(path, bufnr)
+      local f = type(ft) == 'function' and ft(path, bufnr) or ft
       if not vim.g.ft_ignore_pat then
-        return ft
+        return f
       end
 
       local re = vim.regex(vim.g.ft_ignore_pat)
-      if re:match_str(path) then
-        return ft
+      if not re:match_str(path) then
+        return f
       end
     end,
     {
       -- Starset matches should always have lowest priority
-      priority = -math.huge,
+      priority = (opts and opts.priority) or -math.huge,
     },
   }
 end
@@ -29,8 +30,73 @@ local function getline(bufnr, start_lnum, end_lnum)
   return table.concat(lines) or ''
 end
 
--- Filetypes based on file extension
+---@private
+--- Get a single line or line-range from the buffer.
+---
+---@param bufnr number|nil The buffer to get the lines from
+---@param start_lnum number The line number of the first line (inclusive, 1-based)
+---@param end_lnum number|nil The line number of the last line (inclusive, 1-based)
+---@return table<string>|string Array of lines, or string when end_lnum is omitted
+function M.getlines(bufnr, start_lnum, end_lnum)
+  if not end_lnum then
+    -- Return a single line as a string
+    return vim.api.nvim_buf_get_lines(bufnr, start_lnum - 1, start_lnum, false)[1]
+  end
+  return vim.api.nvim_buf_get_lines(bufnr, start_lnum - 1, end_lnum, false)
+end
+
+---@private
+--- Check whether a string matches any of the given Lua patterns.
+---
+---@param s string The string to check
+---@param patterns table<string> A list of Lua patterns
+---@return boolean `true` if s matched a pattern, else `false`
+function M.findany(s, patterns)
+  if s == nil then
+    return false
+  end
+  for _, v in ipairs(patterns) do
+    if s:find(v) then
+      return true
+    end
+  end
+  return false
+end
+
+---@private
+--- Get the next non-whitespace line in the buffer.
+---
+---@param bufnr number The buffer to get the line from
+---@param start_lnum number The line number of the first line to start from (inclusive, 1-based)
+---@return string|nil The first non-blank line if found or `nil` otherwise
+function M.nextnonblank(bufnr, start_lnum)
+  for _, line in ipairs(M.getlines(bufnr, start_lnum, -1)) do
+    if not line:find('^%s*$') then
+      return line
+    end
+  end
+  return nil
+end
+
+---@private
+--- Check whether the given string matches the Vim regex pattern.
+M.matchregex = (function()
+  local cache = {}
+  return function(s, pattern)
+    if s == nil then
+      return nil
+    end
+    if not cache[pattern] then
+      cache[pattern] = vim.regex(pattern)
+    end
+    return cache[pattern]:match_str(s)
+  end
+end)()
+
 -- luacheck: push no unused args
+-- luacheck: push ignore 122
+
+-- Filetypes based on file extension
 ---@diagnostic disable: unused-local
 local extension = {
   -- BEGIN EXTENSION
@@ -178,6 +244,7 @@ local extension = {
   diff = 'diff',
   rej = 'diff',
   Dockerfile = 'dockerfile',
+  dockerfile = 'dockerfile',
   bat = 'dosbatch',
   wrap = 'dosini',
   ini = 'dosini',
@@ -1032,7 +1099,7 @@ local extension = {
   end,
   txt = function(path, bufnr)
     --helpfiles match *.txt, but should have a modeline as last line
-    if not getline(bufnr, -1):match('vim:.*ft=help') then
+    if not getline(bufnr, -1):find('vim:.*ft=help') then
       return 'text'
     end
   end,
@@ -1175,6 +1242,67 @@ local extension = {
       return 'rc'
     end
   end,
+  control = function(path, bufnr)
+    return require('vim.filetype.detect').control(bufnr)
+  end,
+  copyright = function(path, bufnr)
+    return require('vim.filetype.detect').copyright(bufnr)
+  end,
+  -- Ignored extensions
+  bak = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  ['dpkg-dist'] = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  ['dpkg-old'] = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  ['dpkg-new'] = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  ['dpkg-bak'] = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  new = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  old = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  orig = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  pacsave = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  pacnew = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  rpmsave = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  rmpnew = function(path, bufnr)
+    local root = vim.fn.fnamemodify(path, ':r')
+    return M.match(root, bufnr)
+  end,
+  ['in'] = function(path, bufnr)
+    if vim.fs.basename(path) ~= 'configure.in' then
+      local root = vim.fn.fnamemodify(path, ':r')
+      return M.match(root, bufnr)
+    end
+  end,
   -- END EXTENSION
 }
 
@@ -1196,8 +1324,9 @@ local filename = {
   ['named.root'] = 'bindzone',
   WORKSPACE = 'bzl',
   BUILD = 'bzl',
-  ['cabal.config'] = 'cabalconfig',
   ['cabal.project'] = 'cabalproject',
+  [vim.env.HOME .. '/cabal.config'] = 'cabalconfig',
+  ['cabal.config'] = 'cabalconfig',
   calendar = 'calendar',
   catalog = 'catalog',
   ['/etc/cdrdao.conf'] = 'cdrdaoconf',
@@ -1355,6 +1484,9 @@ local filename = {
   ['/etc/nanorc'] = 'nanorc',
   Neomuttrc = 'neomuttrc',
   ['.netrc'] = 'netrc',
+  NEWS = function(path, bufnr)
+    return require('vim.filetype.detect').news(bufnr)
+  end,
   ['.ocamlinit'] = 'ocaml',
   ['.octaverc'] = 'octave',
   octaverc = 'octave',
@@ -1380,15 +1512,28 @@ local filename = {
   ['/etc/pinforc'] = 'pinfo',
   ['/.pinforc'] = 'pinfo',
   ['.povrayrc'] = 'povini',
+  ['printcap'] = function(path, bufnr)
+    vim.b[bufnr].ptcap_type = 'print'
+    return 'ptcap'
+  end,
+  ['termcap'] = function(path, bufnr)
+    vim.b[bufnr].ptcap_type = 'term'
+    return 'ptcap'
+  end,
   ['.procmailrc'] = 'procmail',
   ['.procmail'] = 'procmail',
   ['/etc/protocols'] = 'protocols',
+  ['INDEX'] = function(path, bufnr)
+    return require('vim.filetype.detect').psf(bufnr)
+  end,
+  ['INFO'] = function(path, bufnr)
+    return require('vim.filetype.detect').psf(bufnr)
+  end,
   ['.pythonstartup'] = 'python',
   ['.pythonrc'] = 'python',
   SConstruct = 'python',
   ratpoisonrc = 'ratpoison',
   ['.ratpoisonrc'] = 'ratpoison',
-  v = 'rcs',
   inputrc = 'readline',
   ['.inputrc'] = 'readline',
   ['.reminders'] = 'remind',
@@ -1458,6 +1603,14 @@ local filename = {
   ['.Xpdefaults'] = 'xdefaults',
   ['xdm-config'] = 'xdefaults',
   ['.Xdefaults'] = 'xdefaults',
+  ['xorg.conf'] = function(path, bufnr)
+    vim.b[bufnr].xf86conf_xfree86_version = 4
+    return 'xf86conf'
+  end,
+  ['xorg.conf-4'] = function(path, bufnr)
+    vim.b[bufnr].xf86conf_xfree86_version = 4
+    return 'xf86conf'
+  end,
   ['/etc/xinetd.conf'] = 'xinetd',
   fglrxrc = 'xml',
   ['/etc/blkid.tab'] = 'xml',
@@ -1528,6 +1681,9 @@ local filename = {
   ['tcsh.tcshrc'] = function(path, bufnr)
     return require('vim.filetype.detect').shell(path, bufnr, 'tcsh')
   end,
+  ['XF86Config'] = function(path, bufnr)
+    return require('vim.filetype.detect').xf86conf(bufnr)
+  end,
   -- END FILENAME
 }
 
@@ -1544,12 +1700,22 @@ local pattern = {
   ['.*bsd'] = 'bsdl',
   ['bzr_log%..*'] = 'bzr',
   ['.*enlightenment/.*%.cfg'] = 'c',
+  ['.*/%.calendar/.*'] = starsetf('calendar'),
+  ['.*/share/calendar/.*/calendar%..*'] = starsetf('calendar'),
+  ['.*/share/calendar/calendar%..*'] = starsetf('calendar'),
   ['.*/etc/defaults/cdrdao'] = 'cdrdaoconf',
   ['.*/etc/cdrdao%.conf'] = 'cdrdaoconf',
   ['.*/etc/default/cdrdao'] = 'cdrdaoconf',
   ['.*hgrc'] = 'cfg',
   ['.*%.%.ch'] = 'chill',
   ['.*%.cmake%.in'] = 'cmake',
+  -- */cmus/rc and */.cmus/rc
+  ['.*/%.?cmus/rc'] = 'cmusrc',
+  -- */cmus/*.theme and */.cmus/*.theme
+  ['.*/%.?cmus/.*%.theme'] = 'cmusrc',
+  ['.*/%.cmus/autosave'] = 'cmusrc',
+  ['.*/%.cmus/command%-history'] = 'cmusrc',
+  ['cvs%d+'] = 'cvs',
   ['.*/debian/changelog'] = 'debchangelog',
   ['.*/debian/control'] = 'debcontrol',
   ['.*/debian/copyright'] = 'debcopyright',
@@ -1572,11 +1738,26 @@ local pattern = {
   ['.*/%.config/git/config'] = 'gitconfig',
   ['.*%.git/config%.worktree'] = 'gitconfig',
   ['.*%.git/worktrees/.*/config%.worktree'] = 'gitconfig',
+  ['.*/git/config'] = function(path, bufnr)
+    if vim.env.XDG_CONFIG_HOME and path:find(vim.env.XDG_CONFIG_HOME .. '/git/config') then
+      return 'gitconfig'
+    end
+  end,
   ['%.gitsendemail%.msg%.......'] = 'gitsendemail',
   ['gkrellmrc_.'] = 'gkrellmrc',
   ['.*/usr/.*/gnupg/options%.skel'] = 'gpg',
   ['.*/%.gnupg/options'] = 'gpg',
   ['.*/%.gnupg/gpg%.conf'] = 'gpg',
+  ['.*/options'] = function(path, bufnr)
+    if vim.env.GNUPGHOME and path:find(vim.env.GNUPGHOME .. '/options') then
+      return 'gpg'
+    end
+  end,
+  ['.*/gpg%.conf'] = function(path, bufnr)
+    if vim.env.GNUPGHOME and path:find(vim.env.GNUPGHOME .. '/gpg%.conf') then
+      return 'gpg'
+    end
+  end,
   ['.*/etc/group'] = 'group',
   ['.*/etc/gshadow'] = 'group',
   ['.*/etc/group%.edit'] = 'group',
@@ -1647,6 +1828,12 @@ local pattern = {
   ['.*/%.pinforc'] = 'pinfo',
   ['.*/etc/pinforc'] = 'pinfo',
   ['.*/etc/protocols'] = 'protocols',
+  ['.*printcap.*'] = starsetf(function(path, bufnr)
+    if vim.fn.did_filetype() == 0 then
+      vim.b[bufnr].ptcap_type = 'print'
+      return 'ptcap'
+    end
+  end),
   ['.*baseq[2-3]/.*%.cfg'] = 'quake',
   ['.*quake[1-3]/.*%.cfg'] = 'quake',
   ['.*id1/.*%.cfg'] = 'quake',
@@ -1671,9 +1858,33 @@ local pattern = {
   ['.*%.swift%.gyb'] = 'swiftgyb',
   ['.*/etc/sysctl%.conf'] = 'sysctl',
   ['.*/etc/sysctl%.d/.*%.conf'] = 'sysctl',
+  ['.*/systemd/.*%.automount'] = 'systemd',
+  ['.*/systemd/.*%.dnssd'] = 'systemd',
+  ['.*/systemd/.*%.link'] = 'systemd',
+  ['.*/systemd/.*%.mount'] = 'systemd',
+  ['.*/systemd/.*%.netdev'] = 'systemd',
+  ['.*/systemd/.*%.network'] = 'systemd',
+  ['.*/systemd/.*%.nspawn'] = 'systemd',
+  ['.*/systemd/.*%.path'] = 'systemd',
+  ['.*/systemd/.*%.service'] = 'systemd',
+  ['.*/systemd/.*%.slice'] = 'systemd',
+  ['.*/systemd/.*%.socket'] = 'systemd',
+  ['.*/systemd/.*%.swap'] = 'systemd',
+  ['.*/systemd/.*%.target'] = 'systemd',
+  ['.*/systemd/.*%.timer'] = 'systemd',
   ['.*/etc/systemd/.*%.conf%.d/.*%.conf'] = 'systemd',
   ['.*/%.config/systemd/user/.*%.d/.*%.conf'] = 'systemd',
   ['.*/etc/systemd/system/.*%.d/.*%.conf'] = 'systemd',
+  ['.*/etc/systemd/system/.*%.d/%.#.*'] = 'systemd',
+  ['.*/etc/systemd/system/%.#.*'] = 'systemd',
+  ['.*/%.config/systemd/user/.*%.d/%.#.*'] = 'systemd',
+  ['.*/%.config/systemd/user/%.#.*'] = 'systemd',
+  ['.*termcap.*'] = starsetf(function(path, bufnr)
+    if vim.fn.did_filetype() == 0 then
+      vim.b[bufnr].ptcap_type = 'term'
+      return 'ptcap'
+    end
+  end),
   ['.*%.t%.html'] = 'tilde',
   ['%.?tmux.*%.conf'] = 'tmux',
   ['%.?tmux.*%.conf.*'] = { 'tmux', { priority = -1 } },
@@ -1719,7 +1930,19 @@ local pattern = {
   ['%.login.*'] = function(path, bufnr)
     return require('vim.filetype.detect').csh(path, bufnr)
   end,
-  ['%.neomuttrc.*'] = starsetf('neomuttrc'),
+  ['Muttrc.*'] = starsetf('muttrc'),
+  ['Muttngrc.*'] = starsetf('muttrc'),
+  -- muttrc* and .muttrc*
+  ['%.?muttrc.*'] = starsetf('muttrc'),
+  -- muttngrc* and .muttngrc*
+  ['%.?muttngrc.*'] = starsetf('muttrc'),
+  ['.*/%.mutt/muttrc.*'] = starsetf('muttrc'),
+  ['.*/%.muttng/muttrc.*'] = starsetf('muttrc'),
+  ['.*/%.muttng/muttngrc.*'] = starsetf('muttrc'),
+  ['Neomuttrc.*'] = starsetf('neomuttrc'),
+  -- neomuttrc* and .neomuttrc*
+  ['%.?neomuttrc.*'] = starsetf('neomuttrc'),
+  ['.*/%.neomutt/neomuttrc.*'] = starsetf('neomuttrc'),
   ['%.profile.*'] = function(path, bufnr)
     return require('vim.filetype.detect').sh(path, bufnr, getline(bufnr, 1))
   end,
@@ -1742,8 +1965,15 @@ local pattern = {
   ['.*%.properties_.._.._.*'] = starsetf('jproperties'),
   ['.*%.vhdl_[0-9].*'] = starsetf('vhdl'),
   ['.*/%.fvwm/.*'] = starsetf('fvwm'),
+  ['.*fvwmrc.*'] = starsetf(function(path, bufnr)
+    vim.b[bufnr].fvwm_version = 1
+    return 'fvwm'
+  end),
+  ['.*fvwm95.*%.hook'] = starsetf(function(path, bufnr)
+    vim.b[bufnr].fvwm_version = 1
+    return 'fvwm'
+  end),
   ['.*/%.gitconfig%.d/.*'] = starsetf('gitconfig'),
-  ['.*/%.neomutt/neomuttrc.*'] = starsetf('neomuttrc'),
   ['.*/Xresources/.*'] = starsetf('xdefaults'),
   ['.*/app%-defaults/.*'] = starsetf('xdefaults'),
   ['.*/bind/db%..*'] = starsetf('bindzone'),
@@ -1763,6 +1993,11 @@ local pattern = {
   ['.*/etc/httpd/sites%-.*/.*'] = starsetf('apache'),
   ['.*/etc/logcheck/.*%.d.*/.*'] = starsetf('logcheck'),
   ['.*/etc/modprobe%..*'] = starsetf('modconf'),
+  ['.*/etc/modutils/.*'] = starsetf(function(path, bufnr)
+    if vim.fn.executable(vim.fn.expand(path)) ~= 1 then
+      return 'modconf'
+    end
+  end),
   ['.*/etc/pam%.d/.*'] = starsetf('pamconf'),
   ['.*/etc/profile'] = function(path, bufnr)
     return require('vim.filetype.detect').sh(path, bufnr, getline(bufnr, 1))
@@ -1785,7 +2020,6 @@ local pattern = {
   ['Dockerfile%..*'] = starsetf('dockerfile'),
   ['JAM.*%..*'] = starsetf('jam'),
   ['Kconfig%..*'] = starsetf('kconfig'),
-  ['Neomuttrc.*'] = starsetf('neomuttrc'),
   ['Prl.*%..*'] = starsetf('jam'),
   ['Xresources.*'] = starsetf('xdefaults'),
   ['[mM]akefile.*'] = starsetf('make'),
@@ -1802,7 +2036,8 @@ local pattern = {
   ['gtkrc.*'] = starsetf('gtkrc'),
   ['httpd%.conf.*'] = starsetf('apache'),
   ['lilo%.conf.*'] = starsetf('lilo'),
-  ['neomuttrc.*'] = starsetf('neomuttrc'),
+  ['Muttrc'] = 'muttrc',
+  ['Muttngrc'] = 'muttrc',
   ['proftpd%.conf.*'] = starsetf('apachestyle'),
   ['reportbug%-.*'] = starsetf('mail'),
   ['sgml%.catalog.*'] = starsetf('catalog'),
@@ -1816,8 +2051,8 @@ local pattern = {
   ['%.article%.%d+'] = 'mail',
   ['pico%.%d+'] = 'mail',
   ['mutt%-.*%-%w+'] = 'mail',
-  ['neomutt%-.*%-%w+'] = 'mail',
   ['muttng%-.*%-%w+'] = 'mail',
+  ['neomutt%-.*%-%w+'] = 'mail',
   ['mutt' .. string.rep('[%w_-]', 6)] = 'mail',
   ['neomutt' .. string.rep('[%w_-]', 6)] = 'mail',
   ['/tmp/SLRN[0-9A-Z.]+'] = 'mail',
@@ -1861,7 +2096,7 @@ local pattern = {
     { priority = -1 },
   },
   ['.*%.[Dd][Aa][Tt]'] = function(path, bufnr)
-    return require('vim.filetype.detect').dat(bufnr)
+    return require('vim.filetype.detect').dat(path, bufnr)
   end,
   ['.*%.[Mm][Oo][Dd]'] = function(path, bufnr)
     return require('vim.filetype.detect').mod(path, bufnr)
@@ -1880,9 +2115,61 @@ local pattern = {
   ['example%.gitolite%.rc'] = 'perl',
   -- Neovim only
   ['.*/queries/.*%.scm'] = 'query', -- tree-sitter queries
+  ['.*,v'] = 'rcs',
+  ['.*/xorg%.conf%.d/.*%.conf'] = function(path, bufnr)
+    vim.b[bufnr].xf86conf_xfree86_version = 4
+    return 'xf86config'
+  end,
+  -- Increase priority to run before the pattern below
+  ['XF86Config%-4'] = starsetf(function(path, bufnr)
+    vim.b[bufnr].xf86conf_xfree86_version = 4
+    return 'xf86config'
+  end, { priority = -math.huge + 1 }),
+  ['XF86Config.*'] = starsetf(function(path, bufnr)
+    vim.b[bufnr].xf86conf_xfree86_version = 4
+    return require('vim.filetype.detect').xf86conf(bufnr)
+  end),
+  ['[cC]hange[lL]og.*'] = starsetf(function(path, bufnr)
+    local line = getline(bufnr, 1):lower()
+    if line:find('; urgency=') then
+      return 'debchangelog'
+    else
+      return 'changelog'
+    end
+  end),
+  ['.*fvwm2rc.*'] = starsetf(function(path, bufnr)
+    if vim.fn.fnamemodify(path, ':e') == 'm4' then
+      return 'fvwm2m4'
+    else
+      vim.b[bufnr].fvwm_version = 2
+      return 'fvwm'
+    end
+  end),
+  ['.*%.[Ll][Oo][Gg]'] = function(path, bufnr)
+    -- Innovation Data Processing
+    -- (refactor of filetype.vim since the patterns are case-insensitive)
+    path = path:lower()
+    if M.findany(path, { 'upstream%.log', 'upstream%..*%.log', '.*%.upstream%.log', 'upstream%-.*%.log' }) then
+      return 'upstreamlog'
+    elseif M.findany(path, { 'upstreaminstall%.log', 'upstreaminstall%..*%.log', '.*%.upstreaminstall%.log' }) then
+      return 'upstreaminstalllog'
+    elseif M.findany(path, { 'usserver%.log', 'usserver%..*%.log', '.*%.usserver%.log' }) then
+      return 'usserverlog'
+    elseif M.findany(path, { 'usw2kagt%.log', 'usws2kagt%..*%.log', '.*%.usws2kagt%.log' }) then
+      return 'usw2kagtlog'
+    end
+  end,
+  -- Ignored extension
+  ['.*~'] = function(path, bufnr)
+    local short = path:gsub('~$', '', 1)
+    if path ~= short and short ~= '' then
+      return M.match(vim.fn.fnameescape(short), bufnr)
+    end
+  end,
   -- END PATTERN
 }
 -- luacheck: pop
+-- luacheck: pop
 
 ---@private
 local function sort_by_priority(t)
diff --git a/runtime/lua/vim/filetype/detect.lua b/runtime/lua/vim/filetype/detect.lua
index b35303eefc..2cc75b026e 100644
--- a/runtime/lua/vim/filetype/detect.lua
+++ b/runtime/lua/vim/filetype/detect.lua
@@ -16,56 +16,10 @@
 
 local M = {}
 
----@private
-local function getlines(bufnr, start_lnum, end_lnum)
-  if not end_lnum then
-    -- Return a single line as a string
-    return vim.api.nvim_buf_get_lines(bufnr, start_lnum - 1, start_lnum, false)[1]
-  end
-  return vim.api.nvim_buf_get_lines(bufnr, start_lnum - 1, end_lnum, false)
-end
-
----@private
-local function findany(s, patterns)
-  if s == nil then
-    return false
-  end
-  for _, v in ipairs(patterns) do
-    if s:find(v) then
-      return true
-    end
-  end
-  return false
-end
-
----@private
-local function nextnonblank(bufnr, start_lnum)
-  for _, line in ipairs(getlines(bufnr, start_lnum, -1)) do
-    if not line:find('^%s*$') then
-      return line
-    end
-  end
-  return nil
-end
-
----@private
-local matchregex = (function()
-  local cache = {}
-  return function(line, pattern)
-    if line == nil then
-      return nil
-    end
-    if not cache[pattern] then
-      cache[pattern] = vim.regex(pattern)
-    end
-    return cache[pattern]:match_str(line)
-  end
-end)()
-
----@private
-local did_filetype = function()
-  return vim.fn.did_filetype() ~= 0
-end
+local getlines = vim.filetype.getlines
+local findany = vim.filetype.findany
+local nextnonblank = vim.filetype.nextnonblank
+local matchregex = vim.filetype.matchregex
 
 -- luacheck: push no unused args
 -- luacheck: push ignore 122
@@ -200,7 +154,7 @@ function M.change(bufnr)
 end
 
 function M.csh(path, bufnr)
-  if did_filetype() then
+  if vim.fn.did_filetype() ~= 0 then
     -- Filetype was already detected
     return
   end
@@ -213,11 +167,15 @@ function M.csh(path, bufnr)
   end
 end
 
--- Determine if a *.dat file is Kuka Robot Language
-function M.dat(bufnr)
+function M.dat(path, bufnr)
+  -- Innovation data processing
+  if findany(path:lower(), { '^upstream%.dat$', '^upstream%..*%.dat$', '^.*%.upstream%.dat$' }) then
+    return 'upstreamdat'
+  end
   if vim.g.filetype_dat then
     return vim.g.filetype_dat
   end
+  -- Determine if a *.dat file is Kuka Robot Language
   local line = nextnonblank(bufnr, 1)
   if matchregex(line, [[\c\v^\s*%(\&\w+|defdat>)]]) then
     return 'krl'
@@ -257,7 +215,7 @@ function M.dep3patch(path, bufnr)
 end
 
 function M.dtrace(bufnr)
-  if did_filetype() then
+  if vim.fn.did_filetype() ~= 0 then
     -- Filetype was already detected
     return
   end
@@ -815,7 +773,7 @@ end
 
 -- Also called from filetype.lua
 function M.sh(path, bufnr, name)
-  if did_filetype() or path:find(vim.g.ft_ignore_pat) then
+  if vim.fn.did_filetype() ~= 0 or path:find(vim.g.ft_ignore_pat) then
     -- Filetype was already detected or detection should be skipped
     return
   end
@@ -848,7 +806,7 @@ end
 -- For shell-like file types, check for an "exec" command hidden in a comment, as used for Tcl.
 -- Also called from scripts.vim, thus can't be local to this script. [TODO]
 function M.shell(path, bufnr, name)
-  if did_filetype() or matchregex(path, vim.g.ft_ignore_pat) then
+  if vim.fn.did_filetype() ~= 0 or matchregex(path, vim.g.ft_ignore_pat) then
     -- Filetype was already detected or detection should be skipped
     return
   end
@@ -1054,6 +1012,49 @@ function M.hw(bufnr)
   end
   return 'virata'
 end
+
+function M.news(bufnr)
+  if getlines(bufnr, 1):lower():find('; urgency=') then
+    return 'debchangelog'
+  end
+end
+
+-- Debian Control
+function M.control(bufnr)
+  if getlines(bufnr, 1):find('^Source:') then
+    return 'debcontrol'
+  end
+end
+
+-- Debian Copyright
+function M.copyright(bufnr)
+  if getlines(bufnr, 1):find('^Format:') then
+    return 'debcopyright'
+  end
+end
+
+-- Software Distributor Product Specification File (POSIX 1387.2-1995)
+function M.psf(bufnr)
+  local line = getlines(bufnr, 1):lower()
+  if
+    findany(
+      line,
+      { '^%s*distribution%s*$', '^%s*installed_software%s*$', '^%s*root%s*$', '^%s*bundle%s*$', '^%s*product%s*$' }
+    )
+  then
+    return 'psf'
+  end
+end
+
+-- XFree86 config
+function M.xfree86(bufnr)
+  local line = getlines(bufnr, 1)
+  if matchregex(line, [[\<XConfigurator\>]]) then
+    vim.b[bufnr].xf86conf_xfree86_version = 3
+    return 'xf86conf'
+  end
+end
+
 -- luacheck: pop
 -- luacheck: pop