mustfail 'push is missing head ref update' +$push_spec2
mustfail 'pushing unexpected ref' $push_spec HEAD:refs/wombat
mustfail 'pushing multiple heads' $push_spec HEAD:refs/dgit/wombat
-mustfail E:'pushing multiple tags|pushing too many similar tags' \
+mustfail E:'pushing multiple tags|pushing too many similar tags|need exactly one archive' \
$push_spec HEAD:refs/tags/$tagpfx/wombat
prep unstable sid