patch 8.2.2695: cursor position reset with nested autocommands

Problem:    Cursor position reset with nested autocommands.
Solution:   Only check and reset line numbers for not nested autocommands.
            (closes #5820)

src/autocmd.c

@@ -2116,14 +2116,16 @@ apply_autocmds_group(
 	    ap->last = FALSE;
 	ap->last = TRUE;
 
-	// make sure cursor and topline are valid
+	if (nesting == 1)
-	check_lnums(TRUE);
+	    // make sure cursor and topline are valid
+	    check_lnums(TRUE);
 
 	do_cmdline(NULL, getnextac, (void *)&patcmd,
 				     DOCMD_NOWAIT|DOCMD_VERBOSE|DOCMD_REPEAT);
 
-	// restore cursor and topline, unless they were changed
+	if (nesting == 1)
-	reset_lnums();
+	    // restore cursor and topline, unless they were changed
+	    reset_lnums();
 
 #ifdef FEAT_EVAL
 	if (eap != NULL)

src/testdir/test_terminal.vim

@@ -2002,5 +2002,32 @@ func Test_terminal_all_ansi_colors()
   call delete('Xcolorscript')
 endfunc
 
+function On_BufFilePost()
+    doautocmd <nomodeline> User UserEvent
+endfunction
+
+func Test_terminal_nested_autocmd()
+  new
+  call setline(1, range(500))
+  $
+  let lastline = line('.')
+
+  augroup TermTest
+    autocmd BufFilePost * call On_BufFilePost()
+    autocmd User UserEvent silent
+  augroup END
+
+  let cmd = Get_cat_123_cmd()
+  let buf = term_start(cmd, #{term_finish: 'close', hidden: 1})
+  call assert_equal(lastline, line('.'))
+
+  call TermWait(buf)
+  exe buf . 'bwipe'
+  call delete('Xtext')
+  augroup TermTest
+    au!
+  augroup END
+endfunc
+
 
 " vim: shiftwidth=2 sts=2 expandtab

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2695,
 /**/
     2694,
 /**/