Merge pull request #33561 from zeertzjq/vim-9.1.1304

vim-patch:9.1.{1304,1327}: filetype: some man files are not recognized

runtime/lua/vim/filetype.lua

@@ -835,6 +835,7 @@ local extension = {
   nix = 'nix',
   norg = 'norg',
   nqc = 'nqc',
+  ['0'] = detect.nroff,
   ['1'] = detect.nroff,
   ['2'] = detect.nroff,
   ['3'] = detect.nroff,
@@ -844,6 +845,23 @@ local extension = {
   ['7'] = detect.nroff,
   ['8'] = detect.nroff,
   ['9'] = detect.nroff,
+  ['0p'] = detect.nroff,
+  ['1p'] = detect.nroff,
+  ['3p'] = detect.nroff,
+  ['1x'] = detect.nroff,
+  ['2x'] = detect.nroff,
+  ['3x'] = detect.nroff,
+  ['4x'] = detect.nroff,
+  ['5x'] = detect.nroff,
+  ['6x'] = detect.nroff,
+  ['7x'] = detect.nroff,
+  ['8x'] = detect.nroff,
+  ['3am'] = detect.nroff,
+  ['3perl'] = detect.nroff,
+  ['3pm'] = detect.nroff,
+  ['3posix'] = detect.nroff,
+  ['3type'] = detect.nroff,
+  n = detect.nroff,
   roff = 'nroff',
   tmac = 'nroff',
   man = 'nroff',

runtime/lua/vim/filetype/detect.lua

@@ -1170,12 +1170,17 @@ function M.news(_, bufnr)
   end
 end
 
---- This function checks if one of the first five lines start with a dot. In
---- that case it is probably an nroff file.
+--- This function checks if one of the first five lines start with a typical
+--- nroff pattern in man files.  In that case it is probably an nroff file.
 --- @type vim.filetype.mapfn
 function M.nroff(_, bufnr)
   for _, line in ipairs(getlines(bufnr, 1, 5)) do
-    if line:find('^%.') then
+    if
+      matchregex(
+        line,
+        [[^\%([.']\s*\%(TH\|D[dt]\|S[Hh]\|d[es]1\?\|so\)\s\+\S\|[.'']\s*ig\>\|\%([.'']\s*\)\?\\"\)]]
+      )
+    then
       return 'nroff'
     end
   end

test/old/testdir/test_filetype.vim

@@ -2918,6 +2918,30 @@ func Test_map_file()
   filetype off
 endfunc
 
+func Test_nroff_file()
+  filetype on
+
+  call writefile(['.TH VIM 1 "YYYY Mth DD"'], 'Xfile.1', 'D')
+  split Xfile.1
+  call assert_equal('nroff', &filetype)
+  bwipe!
+
+  call writefile(['.Dd $Mdocdate$', '.Dt "DETECTION TEST" "7"', '.Os'], 'Xfile.7', 'D')
+  split Xfile.7
+  call assert_equal('nroff', &filetype)
+  bwipe!
+
+  call writefile(['''\" t'], 'Xfile.3p', 'D')
+  split Xfile.3p
+  call assert_equal('nroff', &filetype)
+  bwipe!
+
+  call writefile(['. /etc/profile'], 'Xfile.1', 'D')
+  split Xfile.1
+  call assert_notequal('nroff', &filetype)
+  bwipe!
+endfunc
+
 func Test_org_file()
   filetype on