patch for https://github.com/vim-jp/issues/issues/765

setwinvar_aucmd_noblock_when_window_does_not_switch.patch

diff --git a/src/eval.c b/src/eval.c
--- a/src/eval.c
+++ b/src/eval.c
@@ -12426,6 +12426,7 @@
     tabpage_T	*tp = NULL;
     tabpage_T	*oldtabpage;
     int		done = FALSE;
+    int		is_switch;
 
 #ifdef FEAT_WINDOWS
     if (off == 1)
@@ -12442,9 +12443,11 @@
 
     if (win != NULL && varname != NULL)
     {
+	is_switch = !(tp == curtab && win == curwin);
 	/* Set curwin to be our win, temporarily.  Also set the tabpage,
 	 * otherwise the window is not valid. */
-	if (switch_win(&oldcurwin, &oldtabpage, win, tp, TRUE) == OK)
+	if (!is_switch ||
+		    switch_win(&oldcurwin, &oldtabpage, win, tp, TRUE) == OK)
 	{
 	    if (*varname == '&')	/* window-local-option */
 	    {
@@ -12465,8 +12468,9 @@
 	    }
 	}
 
-	/* restore previous notion of curwin */
-	restore_win(oldcurwin, oldtabpage, TRUE);
+	if (is_switch)
+	    /* restore previous notion of curwin */
+	    restore_win(oldcurwin, oldtabpage, TRUE);
     }
 
     if (!done && argvars[off + 2].v_type != VAR_UNKNOWN)
@@ -17597,6 +17601,7 @@
 #ifdef FEAT_WINDOWS
     win_T	*save_curwin;
     tabpage_T	*save_curtab;
+    int		is_switch;
 #endif
     char_u	*varname, *winvarname;
     typval_T	*varp;
@@ -17619,7 +17624,9 @@
     if (win != NULL && varname != NULL && varp != NULL)
     {
 #ifdef FEAT_WINDOWS
-	if (switch_win(&save_curwin, &save_curtab, win, tp, TRUE) == OK)
+	is_switch = !(tp == curtab && win == curwin);
+	if (!is_switch ||
+		    switch_win(&save_curwin, &save_curtab, win, tp, TRUE) == OK)
 #endif
 	{
 	    if (*varname == '&')
@@ -17647,7 +17654,8 @@
 	    }
 	}
 #ifdef FEAT_WINDOWS
-	restore_win(save_curwin, save_curtab, TRUE);
+	if (is_switch)
+	    restore_win(save_curwin, save_curtab, TRUE);
 #endif
     }
 }