ZLE: missing edit-buffer widget

[rooom <rooom@prokonto.pl>]

Hi,

Sometimes I want to edit multi line command with <up>/<down> arrows
and in these cases push-line-or-edit widget is very helpful.
However if activated for single line command it is equivalent to push-line 
(according to manual), so that I have to hit additional enter to get
the line back.

I'm looking for widget "edit-line" or "edit-buffer" which move entire
command line into editor buffer regardless if it is single line or 
multi-line construct.

For some reason the simple definition doesn't work:

push-input-get-line () {
    zle .push-input
    zle .get-line
}
zle -N push-input-get-line

Any suggestion?