vim-patch:9.1.0047: issues with temp curwin/buf while cmdwin is open

Problem:  Things that temporarily change/restore curwin/buf (e.g:
          win_execute, some autocmds) may break assumptions that
          curwin/buf is the cmdwin when "cmdwin_type != 0", causing
          issues.

Solution: Expose the cmdwin's real win/buf and check that instead. Also
          try to ensure these variables are NULL if "cmdwin_type == 0",
          allowing them to be used directly in most cases without
          checking cmdwin_type. (Sean Dewar)

Reset and save `cmdwin_old_curwin` in a similar fashion.
Apply suitable changes for API functions and add Lua tests.

https://github.com/vim/vim/commit/988f74311c26ea9917e84fbae608de226dba7e5f

1 files changed, 7 insertions, 1 deletions

diff --git a/src/nvim/ex_getln.c b/src/nvim/ex_getln.c
index 2c5c291216..f49652fc92 100644
--- a/src/nvim/ex_getln.c
+++ b/src/nvim/ex_getln.c
@@ -4326,9 +4326,10 @@ static int open_cmdwin(void)
   // Don't let quitting the More prompt make this fail.
   got_int = false;
 
-  // Set "cmdwin_type" before any autocommands may mess things up.
+  // Set "cmdwin_..." variables before any autocommands may mess things up.
   cmdwin_type = get_cmdline_type();
   cmdwin_level = ccline.level;
+  cmdwin_win = curwin;
   cmdwin_old_curwin = old_curwin;
 
   // Create empty command-line buffer.
@@ -4337,9 +4338,12 @@ static int open_cmdwin(void)
     win_close(curwin, true, false);
     ga_clear(&winsizes);
     cmdwin_type = 0;
+    cmdwin_win = NULL;
     cmdwin_old_curwin = NULL;
     return Ctrl_C;
   }
+  cmdwin_buf = curbuf;
+
   // Command-line buffer has bufhidden=wipe, unlike a true "scratch" buffer.
   set_option_value_give_err(kOptBufhidden, STATIC_CSTR_AS_OPTVAL("wipe"), OPT_LOCAL);
   curbuf->b_p_ma = true;
@@ -4434,6 +4438,8 @@ static int open_cmdwin(void)
 
   cmdwin_type = 0;
   cmdwin_level = 0;
+  cmdwin_buf = NULL;
+  cmdwin_win = NULL;
   cmdwin_old_curwin = NULL;
 
   exmode_active = save_exmode;