patch 8.2.1259: empty group in 'tabline' may cause using an invalid pointer
Problem: Empty group in 'tabline' may cause using an invalid pointer.
Solution: Set the group start position. (closes #6505)
diff --git a/src/testdir/test_tabline.vim b/src/testdir/test_tabline.vim
index eff9508..6cfed7d 100644
--- a/src/testdir/test_tabline.vim
+++ b/src/testdir/test_tabline.vim
@@ -112,4 +112,27 @@
%bw!
endfunc
+function EmptyTabname()
+ return ""
+endfunction
+
+function MakeTabLine() abort
+ let titles = map(range(1, tabpagenr('$')), '"%( %" . v:val . "T%{EmptyTabname()}%T %)"')
+ let sep = 'あ'
+ let tabpages = join(titles, sep)
+ return tabpages .. sep .. '%=%999X X'
+endfunction
+
+func Test_tabline_empty_group()
+ " this was reading invalid memory
+ set tabline=%!MakeTabLine()
+ tabnew
+ redraw!
+
+ tabclose
+ set tabline=
+endfunc
+
+
+
" vim: shiftwidth=2 sts=2 expandtab