vim-patch:9.1.0616: filetype: Make syntax highlighting off for MS Makefiles (#29874)

Problem:  filetype: Make syntax highlighting off for MS Makefiles
Solution: Try to detect MS Makefiles and adjust syntax rules to it.
          (Ken Takata)

Highlighting of variable expansion in Microsoft Makefile can be broken.
E.g.:
2979cfc262/src/Make_mvc.mak (L1331)

Don't use backslash as escape characters if `make_microsoft` is set.
Also fix that `make_no_comments` was not considered if `make_microsoft`
was set.

Also add description for `make_microsoft` and `make_no_comments` to the
documentation and include a very simple filetype test

closes: vim/vim#15341

eb4b903c9b

Co-authored-by: Ken Takata <kentkt@csc.jp>

runtime/doc/syntax.txt

@@ -1806,7 +1806,7 @@ By default mail.vim synchronises syntax to 100 lines before the first
 displayed line.  If you have a slow machine, and generally deal with emails
 with short headers, you can change this to a smaller value: >
 
-    :let mail_minlines = 30
+	:let mail_minlines = 30
 
 
 MAKE						*make.vim* *ft-make-syntax*
@@ -1817,6 +1817,16 @@ feature off by using: >
 
 	:let make_no_commands = 1
 
+Comments are also highlighted by default.  You can turn this off by using: >
+
+	:let make_no_comments = 1
+
+Microsoft Makefile handles variable expansion and comments differently
+(backslashes are not used for escape).  If you see any wrong highlights
+because of this, you can try this: >
+
+	:let make_microsoft = 1
+
 
 MAPLE						*maple.vim* *ft-maple-syntax*
 

runtime/lua/vim/filetype.lua

@@ -693,8 +693,8 @@ local extension = {
     return not (path:find('html%.m4$') or path:find('fvwm2rc')) and 'm4' or nil
   end,
   eml = 'mail',
-  mk = 'make',
-  mak = 'make',
+  mk = detect.make,
+  mak = detect.make,
   page = 'mallard',
   map = 'map',
   mws = 'maple',
@@ -2122,7 +2122,7 @@ local pattern = {
     ['^Containerfile%.'] = starsetf('dockerfile'),
     ['^Dockerfile%.'] = starsetf('dockerfile'),
     ['^[jJ]ustfile$'] = 'just',
-    ['[mM]akefile$'] = 'make',
+    ['[mM]akefile$'] = detect.make,
     ['^[mM]akefile'] = starsetf('make'),
     ['^[rR]akefile$'] = 'ruby',
     ['^[rR]akefile'] = starsetf('ruby'),

runtime/lua/vim/filetype/detect.lua

@@ -972,6 +972,24 @@ local function m4(contents)
   end
 end
 
+--- Check if it is a Microsoft Makefile
+--- @type vim.filetype.mapfn
+function M.make(_, bufnr)
+  vim.b.make_microsoft = nil
+  for _, line in ipairs(getlines(bufnr, 1, 1000)) do
+    if matchregex(line, [[\c^\s*!\s*\(ifn\=\(def\)\=\|include\|message\|error\)\>]]) then
+      vim.b.make_microsoft = 1
+      break
+    elseif
+      matchregex(line, [[^ *ifn\=\(eq\|def\)\>]])
+      or findany(line, { '^ *[-s]?%s', '^ *%w+%s*[!?:+]=' })
+    then
+      break
+    end
+  end
+  return 'make'
+end
+
 --- @type vim.filetype.mapfn
 function M.markdown(_, _)
   return vim.g.filetype_md or 'markdown'

runtime/syntax/make.vim

@@ -28,8 +28,13 @@ syn match makePreCondit "^!\s*\(cmdswitches\|error\|message\|include\|if\|ifdef\
 syn case match
 
 " identifiers
-syn region makeIdent	start="\$(" skip="\\)\|\\\\" end=")" contains=makeStatement,makeIdent
-syn region makeIdent	start="\${" skip="\\}\|\\\\" end="}" contains=makeStatement,makeIdent
+if exists("b:make_microsoft") || exists("make_microsoft")
+  syn region makeIdent	start="\$(" end=")" contains=makeStatement,makeIdent
+  syn region makeIdent	start="\${" end="}" contains=makeStatement,makeIdent
+else
+  syn region makeIdent	start="\$(" skip="\\)\|\\\\" end=")" contains=makeStatement,makeIdent
+  syn region makeIdent	start="\${" skip="\\}\|\\\\" end="}" contains=makeStatement,makeIdent
+endif
 syn match makeIdent	"\$\$\w*"
 syn match makeIdent	"\$[^({]"
 syn match makeIdent	"^ *[^:#= \t]*\s*[:+?!*]="me=e-2
@@ -78,11 +83,13 @@ syn match makeOverride	"^ *override\>"
 syn match makeStatement contained "(\(abspath\|addprefix\|addsuffix\|and\|basename\|call\|dir\|error\|eval\|file\|filter-out\|filter\|findstring\|firstword\|flavor\|foreach\|guile\|if\|info\|join\|lastword\|notdir\|or\|origin\|patsubst\|realpath\|shell\|sort\|strip\|subst\|suffix\|value\|warning\|wildcard\|word\|wordlist\|words\)\>"ms=s+1
 
 " Comment
-if exists("make_microsoft")
-   syn match  makeComment "#.*" contains=@Spell,makeTodo
-elseif !exists("make_no_comments")
-   syn region  makeComment	start="#" end="^$" end="[^\\]$" keepend contains=@Spell,makeTodo
-   syn match   makeComment	"#$" contains=@Spell
+if !exists("make_no_comments")
+  if exists("b:make_microsoft") || exists("make_microsoft")
+    syn match   makeComment	"#.*" contains=@Spell,makeTodo
+  else
+    syn region  makeComment	start="#" end="^$" end="[^\\]$" keepend contains=@Spell,makeTodo
+    syn match   makeComment	"#$" contains=@Spell
+  endif
 endif
 syn keyword makeTodo TODO FIXME XXX contained
 

test/old/testdir/test_filetype.vim

@@ -2641,4 +2641,21 @@ func Test_pl_file()
   filetype off
 endfunc
 
+func Test_make_file()
+  filetype on
+
+  " Microsoft Makefile
+  call writefile(['# Makefile for Windows', '!if "$(VIMDLL)" == "yes"'], 'XMakefile.mak', 'D')
+  split XMakefile.mak
+  call assert_equal(1, get(b:, 'make_microsoft', 0))
+  bwipe!
+
+  call writefile(['# get the list of tests', 'include testdir/Make_all.mak'], 'XMakefile.mak', 'D')
+  split XMakefile.mak
+  call assert_equal(0, get(b:, 'make_microsoft', 0))
+  bwipe!
+
+  filetype off
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab