func TestBtrfsCreateEmpty(t *testing.T) { graphtest.DriverTestCreateEmpty(t, "btrfs") }
func TestOverlayCreateEmpty(t *testing.T) { graphtest.DriverTestCreateEmpty(t, "overlay") }
func TestDevmapperCreateEmpty(t *testing.T) { graphtest.DriverTestCreateEmpty(t, "devicemapper") }
func TestVfsCreateEmpty(t *testing.T) { graphtest.DriverTestCreateEmpty(t, "vfs") }