Can the focus ring of a DSLR rotate infinitely?

For Nikon and Canon autofocus lenses, any lens with manual priority autofocus function (usually mid-to-high-end lenses with advanced ring motors) can rotate infinitely because there is an automatic clutch device inside. But for lenses without manual priority autofocus, the focus ring is limited at both ends.

For example, the Nikon 18-55 lens cannot be mounted on a lens, but the Nikon 18-70 lens can.