vim-patch:9.1.1203: matchparen keeps cursor on case label in sh filetype (#32900)

Problem:  matchparen keeps cursor on case label in sh filetype
          (@categorical, after 9.1.1187).
Solution: Use :defer so that cursor is always restored, remove checks
          for older Vims, finish early if Vim does not support :defer

fixes: vim/vim#16887
closes: vim/vim#16888

47071c6076

runtime/plugin/matchparen.vim

@@ -1,12 +1,14 @@
 " Vim plugin for showing matching parens
 " Maintainer:	The Vim Project <https://github.com/vim/vim>
-" Last Change:	2025 Mar 08
+" Last Change:	2025 Mar 14
 " Former Maintainer:	Bram Moolenaar <Bram@vim.org>
 
 " Exit quickly when:
 " - this plugin was already loaded (or disabled)
 " - when 'compatible' is set
-if exists("g:loaded_matchparen") || &cp
+" - Vim has no support for :defer
+if exists("g:loaded_matchparen") || &cp ||
+      \ exists(":defer") != 2
   finish
 endif
 let g:loaded_matchparen = 1
@@ -21,17 +23,13 @@ if !exists("g:matchparen_disable_cursor_hl")
   let g:matchparen_disable_cursor_hl = 0
 endif
 
-let s:has_matchaddpos = exists('*matchaddpos')
-
 augroup matchparen
   " Replace all matchparen autocommands
   autocmd! CursorMoved,CursorMovedI,WinEnter,WinScrolled * call s:Highlight_Matching_Pair()
   autocmd! BufWinEnter * autocmd SafeState * ++once call s:Highlight_Matching_Pair()
   autocmd! WinLeave,BufLeave * call s:Remove_Matches()
-  if exists('##TextChanged')
   autocmd! TextChanged,TextChangedI * call s:Highlight_Matching_Pair()
   autocmd! TextChangedP * call s:Remove_Matches()
-  endif
 augroup END
 
 " Skip the rest if it was already done.
@@ -97,14 +95,9 @@ func s:Highlight_Matching_Pair()
   " Find the match.  When it was just before the cursor move it there for a
   " moment.
   if before > 0
-    let has_getcurpos = exists("*getcurpos")
-    if has_getcurpos
-      " getcurpos() is more efficient but doesn't exist before 7.4.313.
     let save_cursor = getcurpos()
-    else
-      let save_cursor = winsaveview()
-    endif
     call cursor(c_lnum, c_col - before)
+    defer setpos('.', save_cursor)
   endif
 
   if !has("syntax") || !exists("g:syntax_on")
@@ -196,31 +189,13 @@ func s:Highlight_Matching_Pair()
     let [m_lnum, m_col] = searchpairpos(c, '', c2, s_flags, s_skip, stopline)
   endtry
 
-  if before > 0
-    if has_getcurpos
-      call setpos('.', save_cursor)
-    else
-      call winrestview(save_cursor)
-    endif
-  endif
-
   " If a match is found setup match highlighting.
   if m_lnum > 0 && m_lnum >= stoplinetop && m_lnum <= stoplinebottom
-    if s:has_matchaddpos
     if !g:matchparen_disable_cursor_hl
       call add(w:matchparen_ids, matchaddpos('MatchParen', [[c_lnum, c_col - before], [m_lnum, m_col]], 10))
     else
       call add(w:matchparen_ids, matchaddpos('MatchParen', [[m_lnum, m_col]], 10))
     endif
-    else
-      if !g:matchparen_disable_cursor_hl
-        exe '3match MatchParen /\(\%' . c_lnum . 'l\%' . (c_col - before) .
-              \ 'c\)\|\(\%' . m_lnum . 'l\%' . m_col . 'c\)/'
-      else
-        exe '3match MatchParen /\(\%' . m_lnum . 'l\%' . m_col . 'c\)/'
-      endif
-      call add(w:matchparen_ids, 3)
-    endif
     let w:paren_hl_on = 1
   endif
 endfunction

test/functional/legacy/matchparen_spec.lua

@@ -4,6 +4,7 @@ local Screen = require('test.functional.ui.screen')
 local clear = n.clear
 local exec = n.exec
 local feed = n.feed
+local poke_eventloop = n.poke_eventloop
 
 describe('matchparen', function()
   before_each(clear)
@@ -238,5 +239,26 @@ describe('matchparen', function()
       {1:~                                       }|*2
                                               |
     ]])
+    -- Send keys one by one so that CursorMoved is triggered.
+    for _, c in ipairs({ 'A', ' ', 'f', 'o', 'o', 'b', 'a', 'r' }) do
+      feed(c)
+      poke_eventloop()
+    end
+    screen:expect([[
+      {18:#!/bin/sh}                               |
+      {25:SUSUWU_PRINT() (}                        |
+        {15:case} {15:"}{100:${LEVEL}}{15:"} {15:in}                    |
+          {15:"}{100:$SUSUWU_SH_NOTICE}{15:")} foobar^         |
+          {100:${SUSUWU_S}} {15:&&} {15:return} {26:1}             |
+        {15:;;}                                    |
+          {15:"}{100:$SUSUWU_SH_DEBUG}{15:")}                 |
+          {100:(}{15:!} {100:${SUSUWU_VERBOSE})} {15:&&} {15:return} {26:1}   |
+        {15:;;}                                    |
+        {15:esac}                                  |
+        {18:# snip}                                |
+      {25:)}                                       |
+      {1:~                                       }|*2
+      {5:-- INSERT --}                            |
+    ]])
   end)
 end)

test/old/testdir/test_plugin_matchparen.vim

@@ -168,6 +168,12 @@ func Test_matchparen_ignore_sh_case()
 
   let buf = RunVimInTerminal('-S '.filename, #{rows: 10})
   call VerifyScreenDump(buf, 'Test_matchparen_sh_case_1', {})
+  " Send keys one by one so that CursorMoved is triggered.
+  for c in 'A foobar'
+    call term_sendkeys(buf, c)
+    call term_wait(buf)
+  endfor
+  call VerifyScreenDump(buf, 'Test_matchparen_sh_case_2', {})
   call StopVimInTerminal(buf)
 endfunc