previous job breaks if it's an alias?

[Mikel Ward <mikel@xxxxxxxxxxxxx>]

With latest git master (9b69e8472):

$ zsh --norcs --noglobalrcs
hostname% vim() { nvim "$@"; }
hostname% vim
^Z
hostname% cat
^Z
hostname% %-
(resumes nvim, as expected)
^Z
hostname% %-
(resumes nvim, should have resumed cat)