vim-patch:9.1.0289: filetype: some TeX files are not recognized (#28291)

Problem:  filetype: some TeX files are not recognized
Solution: Add more patterns for TeX files and inspect
          a few more files for being TeX files
          (Wu, Zhenyu)

closes: vim/vim#14456

https://github.com/vim/vim/commit/61ee833a504ae73bc6b3e2527a81582263f02afd

Co-authored-by: Wu, Zhenyu <wuzhenyu@ustc.edu>

3 files changed, 31 insertions, 4 deletions

diff --git a/runtime/lua/vim/filetype.lua b/runtime/lua/vim/filetype.lua
index bbe1e2c89c..06761fefe9 100644
--- a/runtime/lua/vim/filetype.lua
+++ b/runtime/lua/vim/filetype.lua
@@ -252,7 +252,7 @@ local extension = {
   capnp = 'capnp',
   cdc = 'cdc',
   cdl = 'cdl',
-  toc = 'cdrtoc',
+  toc = detect_line1('\\contentsline', 'tex', 'cdrtoc'),
   cfc = 'cf',
   cfm = 'cf',
   cfi = 'cf',
@@ -631,7 +631,7 @@ local extension = {
   livemd = 'livebook',
   lgt = 'logtalk',
   lotos = 'lotos',
-  lot = 'lotos',
+  lot = detect_line1('\\contentsline', 'tex', 'lotos'),
   lout = 'lout',
   lou = 'lout',
   ulpc = 'lpc',
@@ -1035,6 +1035,27 @@ local extension = {
   bbl = 'tex',
   latex = 'tex',
   sty = 'tex',
+  pgf = 'tex',
+  nlo = 'tex',
+  nls = 'tex',
+  out = 'tex',
+  thm = 'tex',
+  eps_tex = 'tex',
+  pygtex = 'tex',
+  pygstyle = 'tex',
+  clo = 'tex',
+  aux = 'tex',
+  brf = 'tex',
+  ind = 'tex',
+  lof = 'tex',
+  loe = 'tex',
+  nav = 'tex',
+  vrb = 'tex',
+  ins = 'tex',
+  tikz = 'tex',
+  bbx = 'tex',
+  cbx = 'tex',
+  beamer = 'tex',
   cls = detect.cls,
   texi = 'texinfo',
   txi = 'texinfo',
@@ -2023,6 +2044,7 @@ local pattern = {
   ['.*termcap.*'] = starsetf(function(path, bufnr)
     return require('vim.filetype.detect').printcap('term')
   end),
+  ['.*/tex/latex/.*%.cfg'] = 'tex',
   ['.*%.t%.html'] = 'tilde',
   ['%.?tmux.*%.conf'] = 'tmux',
   ['%.?tmux.*%.conf.*'] = { 'tmux', { priority = -1 } },
diff --git a/runtime/lua/vim/filetype/detect.lua b/runtime/lua/vim/filetype/detect.lua
index ca2c53b75d..c48984d151 100644
--- a/runtime/lua/vim/filetype/detect.lua
+++ b/runtime/lua/vim/filetype/detect.lua
@@ -458,6 +458,9 @@ end
 
 --- @type vim.filetype.mapfn
 function M.def(_, bufnr)
+  if getline(bufnr, 1):find('%%%%') then
+    return 'tex'
+  end
   if vim.g.filetype_def == 'modula2' or is_modula2(bufnr) then
     return modula2(bufnr)
   end
@@ -738,7 +741,9 @@ end
 
 --- @type vim.filetype.mapfn
 function M.inp(_, bufnr)
-  if getline(bufnr, 1):find('^%*') then
+  if getline(bufnr, 1):find('%%%%') then
+    return 'tex'
+  elseif getline(bufnr, 1):find('^%*') then
     return 'abaqus'
   else
     for _, line in ipairs(getlines(bufnr, 1, 500)) do
diff --git a/test/old/testdir/test_filetype.vim b/test/old/testdir/test_filetype.vim
index 94890aaa40..5d6c7d2874 100644
--- a/test/old/testdir/test_filetype.vim
+++ b/test/old/testdir/test_filetype.vim
@@ -736,7 +736,7 @@ func s:GetFilenameChecks() abort
     \ 'teraterm': ['file.ttl'],
     \ 'terminfo': ['file.ti'],
     \ 'terraform-vars': ['file.tfvars'],
-    \ 'tex': ['file.latex', 'file.sty', 'file.dtx', 'file.ltx', 'file.bbl'],
+    \ 'tex': ['file.latex', 'file.sty', 'file.dtx', 'file.ltx', 'file.bbl', 'any/.texlive/texmf-config/tex/latex/file/file.cfg', 'file.pgf', 'file.nlo', 'file.nls', 'file.out', 'file.thm', 'file.eps_tex', 'file.pygtex', 'file.pygstyle', 'file.clo', 'file.aux', 'file.brf', 'file.ind', 'file.lof', 'file.loe', 'file.nav', 'file.vrb', 'file.ins', 'file.tikz', 'file.bbx', 'file.cbx', 'file.beamer'],
     \ 'texinfo': ['file.texinfo', 'file.texi', 'file.txi'],
     \ 'texmf': ['texmf.cnf'],
     \ 'text': ['file.text', 'file.txt', 'README', 'LICENSE', 'COPYING', 'AUTHORS', '/usr/share/doc/bash-completion/AUTHORS', '/etc/apt/apt.conf.d/README', '/etc/Muttrc.d/README'],