patch 8.1.1756: autocommand that splits window messes up window layoutv8.1.1756

Problem:    Autocommand that splits window messes up window layout.
Solution:   Disallow splitting a window while closing one.  In ":all" give an
            error when moving a window will not work.

1 files changed, 7 insertions, 0 deletions

diff --git a/src/buffer.c b/src/buffer.c
index 55bcc829ab..4e60751eb4 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -5101,6 +5101,13 @@ do_arg_all(
 			    new_curwin = wpnext;
 			    new_curtab = curtab;
 			}
+			else if (wpnext->w_frame->fr_parent
+						 != curwin->w_frame->fr_parent)
+			{
+			    emsg(_("E249: window layout changed unexpectedly"));
+			    i = count;
+			    break;
+			}
 			else
 			    win_move_after(wpnext, curwin);
 			break;