vim-patch:9.0.2128: runtime(swig): add syntax and filetype plugins

Add syntax and filetype plugins for SWIG (Simplified Wrapper Interface
Generator) description files.

The default syntax for .i files highlights comments in a reverse
color scheme which doesn't look well.  This syntax builds
on vim's c++ syntax by adding highlighting for common swig
directives and user defined directives.  For an alternative
syntax, see vimscript vim/vim#1247 (which I found after writing this).

closes: vim/vim#13562

https://github.com/vim/vim/commit/2e31065a650015892179e520038bf2083a9519b6

Co-authored-by: Julien Marrec <julien.marrec@gmail.com>
Co-authored-by: Matěj Cepl <mcepl@cepl.eu>

2 files changed, 28 insertions, 21 deletions

diff --git a/runtime/lua/vim/filetype.lua b/runtime/lua/vim/filetype.lua
index 217f673b5e..cb2656d9ba 100644
--- a/runtime/lua/vim/filetype.lua
+++ b/runtime/lua/vim/filetype.lua
@@ -984,6 +984,8 @@ local extension = {
   svelte = 'svelte',
   svg = 'svg',
   swift = 'swift',
+  swig = 'swig',
+  swg = 'swig',
   svh = 'systemverilog',
   sv = 'systemverilog',
   cmm = 'trace32',
@@ -1134,7 +1136,7 @@ local extension = {
   web = detect.web,
   pl = detect.pl,
   pp = detect.pp,
-  i = detect.progress_asm,
+  i = detect.i,
   w = detect.progress_cweb,
   p = detect.progress_pascal,
   pro = detect_seq(detect.proto, 'idlang'),
diff --git a/runtime/lua/vim/filetype/detect.lua b/runtime/lua/vim/filetype/detect.lua
index 5479608148..9d0f1bd3ab 100644
--- a/runtime/lua/vim/filetype/detect.lua
+++ b/runtime/lua/vim/filetype/detect.lua
@@ -619,6 +619,31 @@ function M.hw(_, bufnr)
   return 'virata'
 end
 
+-- This function checks for an assembly comment or a SWIG keyword or verbatim
+-- block in the first 50 lines.
+-- If not found, assume Progress.
+--- @type vim.filetype.mapfn
+function M.i(path, bufnr)
+  if vim.g.filetype_i then
+    return vim.g.filetype_i
+  end
+
+  -- These include the leading '%' sign
+  local ft_swig_keywords =
+    [[^\s*%\%(addmethods\|apply\|beginfile\|clear\|constant\|define\|echo\|enddef\|endoffile\|extend\|feature\|fragment\|ignore\|import\|importfile\|include\|includefile\|inline\|insert\|keyword\|module\|name\|namewarn\|native\|newobject\|parms\|pragma\|rename\|template\|typedef\|typemap\|types\|varargs\|warn\)]]
+  -- This is the start/end of a block that is copied literally to the processor file (C/C++)
+  local ft_swig_verbatim_block_start = '^%s*%%{'
+
+  for _, line in ipairs(getlines(bufnr, 1, 50)) do
+    if line:find('^%s*;') or line:find('^%*') then
+      return M.asm(path, bufnr)
+    elseif matchregex(line, ft_swig_keywords) or line:find(ft_swig_verbatim_block_start) then
+      return 'swig'
+    end
+  end
+  return 'progress'
+end
+
 --- @type vim.filetype.mapfn
 function M.idl(_, bufnr)
   for _, line in ipairs(getlines(bufnr, 1, 50)) do
@@ -1016,26 +1041,6 @@ function M.printcap(ptcap_type)
   end
 end
 
--- This function checks for an assembly comment in the first ten lines.
--- If not found, assume Progress.
---- @type vim.filetype.mapfn
-function M.progress_asm(path, bufnr)
-  if vim.g.filetype_i then
-    return vim.g.filetype_i
-  end
-
-  for _, line in ipairs(getlines(bufnr, 1, 10)) do
-    if line:find('^%s*;') or line:find('^/%*') then
-      return M.asm(path, bufnr)
-    elseif not line:find('^%s*$') or line:find('^/%*') then
-      -- Not an empty line: doesn't look like valid assembly code
-      -- or it looks like a Progress /* comment.
-      break
-    end
-  end
-  return 'progress'
-end
-
 --- @type vim.filetype.mapfn
 function M.progress_cweb(_, bufnr)
   if vim.g.filetype_w then