fix(cmdline): avoid 'incsearch' recursion after redraw #39303

Problem:  A vim.ui_attach() callback that redraws to show a 'verbose'
          regex message during 'incsearch' results in recusive redrawing.

Solution: Check that curwin was redrawn instead of just any window when
          determining if 'incsearch' highlighting was cleared.

3 files changed, 5 insertions, 2 deletions

diff --git a/src/nvim/buffer_defs.h b/src/nvim/buffer_defs.h
index 72e67d4fd6..90845531f4 100644
--- a/src/nvim/buffer_defs.h
+++ b/src/nvim/buffer_defs.h
@@ -1294,6 +1294,7 @@ struct window_S {
   bool w_redr_status;               // if true statusline/winbar must be redrawn
   bool w_redr_border;               // if true border must be redrawn
   bool w_redr_statuscol;            // if true 'statuscolumn' must be redrawn
+  disptick_T w_display_tick;        // when window was last drawn.
 
   // remember what is shown in the 'statusline'-format elements
   pos_T w_stl_cursor;                // cursor position when last redrawn
diff --git a/src/nvim/drawscreen.c b/src/nvim/drawscreen.c
index 35f4691726..a7fa6bf688 100644
--- a/src/nvim/drawscreen.c
+++ b/src/nvim/drawscreen.c
@@ -2321,6 +2321,8 @@ redr_statuscol:
 
   wp->w_lines_valid = MAX(wp->w_lines_valid, idx);
 
+  wp->w_display_tick = display_tick;
+
   // Let the syntax stuff know we stop parsing here.
   if (syntax_last_parsed != 0 && syntax_present(wp)) {
     syntax_end_parsing(wp, syntax_last_parsed + 1);
diff --git a/src/nvim/ex_getln.c b/src/nvim/ex_getln.c
index 6cc697cc6e..5f384c6ee4 100644
--- a/src/nvim/ex_getln.c
+++ b/src/nvim/ex_getln.c
@@ -1291,7 +1291,7 @@ static int command_line_execute(VimState *state, int key)
     return -1;  // get another key
   }
 
-  disptick_T display_tick_saved = display_tick;
+  disptick_T display_tick_saved = curwin->w_display_tick;
   CommandLineState *s = (CommandLineState *)state;
   s->c = key;
 
@@ -1322,7 +1322,7 @@ static int command_line_execute(VimState *state, int key)
       init_incsearch_state(&s->is_state);
     }
     // Re-apply 'incsearch' highlighting in case it was cleared.
-    if (display_tick > display_tick_saved && s->is_state.did_incsearch) {
+    if (curwin->w_display_tick > display_tick_saved && s->is_state.did_incsearch) {
       may_do_incsearch_highlighting(s->firstc, s->count, &s->is_state);
     }
     // If f_setcmdline() changed the cmdline treat it as such.