vi: correctly record deleted characters

The undo queue didn't record deleted characters properly.  For
example, insert some text, backspace over a couple of characters
then exit insert mode.  At this point undo will restore two nulls
instead of the deleted characters.

The fix is in undo_push():  record the state of the UNDO_USE_SPOS
flag and clear it before using 'u_type'.

Also, update the comments to reflect the fact that UNDO_QUEUED_FLAG
isn't actually used.

function                                             old     new   delta
undo_push                                            443     435      -8
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8)               Total: -8 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
1 file changed