From 9d02fc4c00f61724610224f91950c51bd2700c97 Mon Sep 17 00:00:00 2001
From: Christian Clason <c.clason@uni-graz.at>
Date: Fri, 21 Jan 2022 16:45:32 +0100
Subject: vim-patch:8.2.4172: filetype detection for BASIC is not optimal
 (#17161)

Problem:    Filetype detection for BASIC is not optimal.
Solution:   Improve BASIC filetype detection. (Doug Kearns)
https://github.com/vim/vim/commit/6517f14165cdebf83a07ab9d4aeeb102b4e16e92
---
 runtime/autoload/dist/ft.vim | 26 +++++++++++++++++++++-----
 runtime/filetype.vim         |  5 +++--
 runtime/lua/vim/filetype.lua |  5 +++--
 3 files changed, 27 insertions(+), 9 deletions(-)

(limited to 'runtime')

diff --git a/runtime/autoload/dist/ft.vim b/runtime/autoload/dist/ft.vim
index 0d6841a35b..69712046a5 100644
--- a/runtime/autoload/dist/ft.vim
+++ b/runtime/autoload/dist/ft.vim
@@ -67,13 +67,29 @@ func dist#ft#FTasmsyntax()
   endif
 endfunc
 
-" Check if one of the first five lines contains "VB_Name".  In that case it is
-" probably a Visual Basic file.  Otherwise it's assumed to be "alt" filetype.
-func dist#ft#FTVB(alt)
-  if getline(1).getline(2).getline(3).getline(4).getline(5) =~? 'VB_Name\|Begin VB\.\(Form\|MDIForm\|UserControl\)'
+func dist#ft#FTbas()
+  if exists("g:filetype_bas")
+    exe "setf " . g:filetype_bas
+    return
+  endif
+
+  " most frequent FreeBASIC-specific keywords in distro files
+  let fb_keywords = '\c^\s*\%(extern\|var\|enum\|private\|scope\|union\|byref\|operator\|constructor\|delete\|namespace\|public\|property\|with\|destructor\|using\)\>\%(\s*[:=(]\)\@!'
+  let fb_preproc  = '\c^\s*\%(#\a\+\|option\s\+\%(byval\|dynamic\|escape\|\%(no\)\=gosub\|nokeyword\|private\|static\)\>\)'
+  let fb_comment  = "^\\s*/'"
+  " OPTION EXPLICIT, without the leading underscore, is common to many dialects
+  let qb64_preproc = '\c^\s*\%($\a\+\|option\s\+\%(_explicit\|_\=explicitarray\)\>\)'
+
+  let lines = getline(1, min([line("$"), 100]))
+
+  if match(lines, fb_preproc) > -1 || match(lines, fb_comment) > -1 || match(lines, fb_keywords) > -1
+    setf freebasic
+  elseif match(lines, qb64_preproc) > -1
+    setf qb64
+  elseif match(lines, '\cVB_Name\|Begin VB\.\(Form\|MDIForm\|UserControl\)') > -1
     setf vb
   else
-    exe "setf " . a:alt
+    setf basic
   endif
 endfunc
 
diff --git a/runtime/filetype.vim b/runtime/filetype.vim
index 73237437dc..f809a47b3f 100644
--- a/runtime/filetype.vim
+++ b/runtime/filetype.vim
@@ -189,7 +189,8 @@ au BufNewFile,BufRead *.awk,*.gawk		setf awk
 au BufNewFile,BufRead *.mch,*.ref,*.imp		setf b
 
 " BASIC or Visual Basic
-au BufNewFile,BufRead *.bas			call dist#ft#FTVB("basic")
+au BufNewFile,BufRead *.bas			call dist#ft#FTbas()
+au BufNewFile,BufRead *.bi,*.bm			call dist#ft#FTbas()
 
 " Visual Basic Script (close to Visual Basic) or Visual Basic .NET
 au BufNewFile,BufRead *.vb,*.vbs,*.dsm,*.ctl	setf vb
@@ -198,7 +199,7 @@ au BufNewFile,BufRead *.vb,*.vbs,*.dsm,*.ctl	setf vb
 au BufNewFile,BufRead *.iba,*.ibi		setf ibasic
 
 " FreeBasic file (similar to QBasic)
-au BufNewFile,BufRead *.fb,*.bi			setf freebasic
+au BufNewFile,BufRead *.fb			setf freebasic
 
 " Batch file for MSDOS.
 au BufNewFile,BufRead *.bat,*.sys		setf dosbatch
diff --git a/runtime/lua/vim/filetype.lua b/runtime/lua/vim/filetype.lua
index 819587bb3e..c7e18bf186 100644
--- a/runtime/lua/vim/filetype.lua
+++ b/runtime/lua/vim/filetype.lua
@@ -220,7 +220,6 @@ local extension = {
   ["f08"] = "fortran",
   fpc = "fpcmake",
   fsl = "framescript",
-  bi = "freebasic",
   fb = "freebasic",
   fsi = "fsharp",
   fsx = "fsharp",
@@ -738,7 +737,9 @@ local extension = {
   PL = function() vim.fn["dist#ft#FTpl"]() end,
   R = function() vim.fn["dist#ft#FTr"]() end,
   asm = function() vim.fn["dist#ft#FTasm"]() end,
-  bas = function() vim.fn["dist#ft#FTVB"]("basic") end,
+  bas = function() vim.fn["dist#ft#FTbas"]() end,
+  bi = function() vim.fn["dist#ft#FTbas"]() end,
+  bm = function() vim.fn["dist#ft#FTbas"]() end,
   bash = function() vim.fn["dist#ft#SetFileTypeSH"]("bash") end,
   btm = function() vim.fn["dist#ft#FTbtm"]() end,
   c = function() vim.fn["dist#ft#FTlpc"]() end,
-- 
cgit