patch 9.0.0218: reading before the start of the line

Problem:    Reading before the start of the line.
Solution:   When displaying "$" check the column is not negative.
diff --git a/src/testdir/test_cmdwin.vim b/src/testdir/test_cmdwin.vim
index d641b29..8cfb248 100644
--- a/src/testdir/test_cmdwin.vim
+++ b/src/testdir/test_cmdwin.vim
@@ -365,5 +365,13 @@
   call assert_match('E1292:', caught)
 endfunc
 
+func Test_cmdwin_virtual_edit()
+  enew!
+  set ve=all cpo+=$
+  silent normal q/s
+
+  set ve= cpo-=$
+endfunc
+
 
 " vim: shiftwidth=2 sts=2 expandtab