Fix redisplay when a window's scroll bar or fringes are changed

* src/window.c (set_window_fringes, set_window_scroll_bars):
Set windows_or_buffers_changed flag to cause immediate
thorough redisplay of a window when scroll bars or fringes are
changed.  (Bug#33694)

diff --git a/src/window.c b/src/window.c
index 5d99098cba158379847adc21f55a92efc83dfc53..6026313e5a4d24b197ad3a14914afd185fd782e5 100644 (file)
--- a/src/window.c
+++ b/src/window.c
@@ -7137,6 +7137,11 @@ set_window_fringes (struct window *w, Lisp_Object left_width,
       w->right_fringe_width = right;
       w->fringes_outside_margins = outside;
 
+      /* This is needed to trigger immediate redisplay of the window
+        when its fringes are changed, because fringes are redrawn
+        only if update_window is called, so we must trigger that even
+        if the window's glyph matrices did not change at all.  */
+      windows_or_buffers_changed = 35;
       return w;
     }
   else
@@ -7254,6 +7259,12 @@ set_window_scroll_bars (struct window *w, Lisp_Object width,
   wset_horizontal_scroll_bar_type (w, Qnil);
 #endif
 
+  /* This is needed to trigger immediate redisplay of the window when
+     scroll bars are changed, because scroll bars are redisplayed only
+     if more than a single window needs to be considered, see
+     redisplay_internal.  */
+  if (changed)
+    windows_or_buffers_changed = 31;
   return changed ? w : NULL;
 }